Dometic RM1303 and Service manual

Dometic
Dometic
AES REFRIGERATOR
DIAGNOSTIC SERVICE
MANUAL
The Dometic Corporation
Corporate Office
2320 Industrial Parkway
Elkhart, In. 46515
219-295-5228
Warranty
Department
205 E. Fenn St.
LaGrange, In. 46761
219-463-2191
Technical Services 509 S. Poplar St.
LaGrange, In. 46761
Department
219-463-4858
OS1160A
11/88
A-l
Diagnostic Service Manuals
TABLE OF CONTENTS
Diagnostic Flow Charts
No Operation . . . .
No 120V AC Operation .
No 12V DC Operation .
No Gas Operation. . .
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A-5- 1
A-5-2
A-5-3
A-5-4
Operation and Diagnosis
Dometic AES Refrigerators
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A-6- 1
Glossary of Terms
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A-7- 1
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A-8- 1
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A-9- 1
AES Refrigerator Manual
Subscription Form . . .
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A-14
.. .
Continuity Readings for
Switch Card and Harness
Service
Bulletins.
A-3
AES REFRIGERATOR
DIAGNOSTIC FLOW CHART
NO OPERATION
A.
Correct coach wiring
as necessary.
(see pgs. A-6-23
to A-6-30
para. 7 9 - 8 4 )
Check supply voltage.
1. Polarity
2. Battery supply
3. Wire size
OK
B.
NOT OK
Replace fuse as
necessary
(see pg. A-6-34,
para. 9 6 )
N
O
T
O
K
Replace thermostat
as necessary
(see pgs. A-6-34
t o A - 6 - 3 5 , para.
97- 100)
Check fuse.
OK
Check thermostat.
t
OK
Replace switch as
necessary
(see pgs. A-6-35
t o A - 6 - 3 6 , para.
100-103; & pgs.
A-8-l to A-8-5)
Check
OK
Replace solenoid as
necessary
(see pg. A-6-36,
para. 104-106)
Check solenoid.
A-5-1
AES REFRIGERATOR
DIAGNOSTIC FLOW CHART
A.
NO 120V AC Operation
Correct coach wiring
Check supply voltage.
1. Polarity
2. Battery supply
3. Wire size
Check AC voltage
NOT
OK
NOT
OK
OK
t o A - 6 - 3 0 , para.
79-84)
Correct coach wiring
and/or power source
(breakers) as necessary
(see pgs. A-6-22 to
A - 6 - 2 3 , para.
75-78)
C.
Check AC heating element
for proper resistance;
Insure proper size
and wattage
N
O
O
T
K
Replace heating element
w/correct size &
wattage as necessary
( s e e pgs. A-6-38 to
A - 6 - 3 9 , para.
111-116)
OK
D.
Check switch
NOT
OK
E.
OK
Replace solenoid as
necessary
(see pg. A-6-36,
para. 104- 106)
Check solenoid
F.
Replace switch as
necessary
(see pgs. A-6-35 to
A - 6 - 3 6 , para.
101-103 & pgs.
A-8-l to A-8-5)
OK
Check AC leads on
printed circuit board
Correct as necessary
(see p g . A - 6 - 3 9 ,
NOT
OK
A-5-2
para. 117)
AES REFRIGERATOR
DIAGNOSTIC FLOW CHART
NO 12 VOLT DC OPERATION
A.
Check
1.
2.
3.
supply voltage
Correct coach wiring as necessary
Polarity
(see pgs. A-6-23 to A-6-30,
Battery supply NOT
para. 7 9 - 8 4 )
Wire size
OK
OK
B.
Check that refrigerator
is wired directly to
12V battery
c.
NOT
OK
OK
Check for proper gauge
wire in 12V installation
D.
I
Correct wiring as necessary
(see pgs. A-6-27 & A - 6 - 2 9 )
Rewire w/proper gauge wire as
necessary (see chart on pg. A-6-26)
NOT
OK
OK
1
Check ignition lock
terminal for 12V when
ignition key is placed
in the “ON” position only NOT
Repair circuit as necessary
(see p g . A - 6 - 4 0 ,
para. 120)
E.
Replace relay as necessary
(see pgs. A-6-41 to
Check DC relay
A - 6 - 4 2 , para. 123-l 27)
NOT
OK
F.
Replace element as necessary
Check 12V DC element
(see pgs. A-6-42 to
A - 6 - 4 3 , para. 128-l 29)
NOT ,
OK
G.
Replace switch as necessary
( s e e p g s . A - 6 - 3 5 t o A - 6 - 3 6 , para.
101-103 8c pgs. A-8-l to
Check switch
H.
OK
Check printed circuit
board & connections
A-8-5)
NOT
OK
t
NOTOK
A-5-3
Correct connections and/or
replace printed circuit
board as necessary (see pgs.
A-11-3 to A-11-5)
AES REFRIGERATOR
DIAGNOSTIC FLOW CHART
NO GAS OPERATION
Check
1.
2.
3.
B.
supply voltage
Polarity
Battery
Wire size
t
Not
OK
-
i
Disconnect supply line
(see p g . A - 6 - 4 4 ,
para. 1 3 4 )
OK
Check that 12V i s not
present at tag line
Repair circuit as
necessary (see pg. A-6-44,
para. 1 3 4 )
I
D.
OK
Check gas pressure
E.
1
OK
Check that 120V AC
is not present
at receptacle
C.
Correct coach wiring as
necessary (see pgs. A-6-23
t o A - 6 - 3 0 , para.
79-84)
NOT
OK
Adjust coach regulator
as necessary (see pgs.
A-6-44 to A-6-45,
para. 1 3 5 - l 3 6 )
OK
Clean flue, clean or
replace burner and
orifice as necessary
( s e e p g . A - 6 - 4 8 , para.
148- 149)
OK
(continued on page A-5-5)
A-5-4
1
AES REFRIGERATOR
DIAGNOSTIC FLOW CHART
NO GAS OPERATION (continued)
G.
OK
NOT
OK
Replace solenoid as
necessary (see pgs.
A-6-45 to A-6-46,
para. 1 3 7 - l 4 0 )
NOT
OK
Replace parts as
necessary and/or
(See pg. A-6-47,
para. 145- 1 4 6 )
Check solenoid
H.
OK
,
Check electrode and
electrode wire
A-5-5
OPERATION AND DIAGNOSIS
DOMETIC AES REFRIGERATORS
A-6- 1
(1)
Welcome to the Dometic A.E.S. refrigerator training program. In this program we will discuss the
features, operating sequences and diagnostic procedures for the Dometic refrigerators that are
equipped with the Automatic Energy Selector Control system; A.E.S. for short.
(2)
With this type of control system the customer
no longer has to manually switch the
refrigerator to the desired mode of operation.
All that is left for the customer to do is to turn
the refrigerator “ON” and to select the desired
temperature range by way of the thermostat
knob. The refrigerator will automatically select
between 120V AC, 12V DC or LP gas to
operate the refrigerator.
(3)
The selection will be made electronically with
the highest priority going to the 12OV AC
cooling mode; second priority going to the 12V
DC heating element, providing the motor
home’s ignition key is turned “ON” and the
vehicle is in motion. Last priority is LP gas
operation.
(4)
Since the introduction of the first A.E.S.
refrigerators in 1983 there have been three
distinct model series or “generations” available.
We will discuss each of the three model generations separately to illustrate the parts location
and operational differences between each
model series.
A-6-2
(5)
Shown here is the RM1303 that is one of the models that make up the
first generation A.E.S. refrigerators. The models in this series include
from the smallest size to the largest size: the RM663 which is a 5 cubic
foot refrigerator, the RM763 which is a 6 cubic foot refrigerator and
lastly, the RM1303 which is an 8 cubic foot refrigerator.
(6)
Let’s now take a closer look at the parts
location and operation of these models. From
the lower front of the refrigerator we can see
the main control panel assembly. This
assembly contains the two control knobs and
the L.E.D. lamp that will illuminate when the
refrigerator is turned on.
(7)
The knob on the right is the main switch that
is used to turn on the refrigerator and the
knob to the left is the thermostat control that
is u s e d t o r e g u l a t e t h e l o w e r c a b i n e t
temperatures within the food zone range.
(8)
When the unit is turned on, the L.E.D. lamp
will illuminate green to let the customer know
that the refrigerator is turned on and that the
system has sufficient DC voltage to operate the
refrigerator.
L.E.D.
Lamp
A-6-3
(9)
It must be remembered that a DC wire hookup to the terminal block is required for any
A.E.S. refrigerator to operate on 120 volts AC,
12 volts DC or LP gas.
(10)
From the rear of our example we can see the
shut-off valve and knob where the main LP
gas supply is connected to the refrigerator, 12
volt DC terminal block where the 12 volt
power source comes into the refrigerator to
operate the system and the LP gas solenoid
valve which includes the 12 millimeter test
plug where the LP gas pressure can be
checked.
(11)
The solenoid valve replaces the user operated
flame failure safety device that is found on the
manually controlled refrigerator models.
(12)
Finally, to the right of the solenoid valve is
the orifice burner assembly which generates
the heat required on the LP gas mode to
operate the absorption cooling unit.
A-6-4
(13)
Just above the burner assembly, located in the
generator section of the cooling unit, are the
12 volt DC and 120 volt AC heating elements
that provide the heat to the cooling unit on
those modes.
(14)
By removing the two screws on the left side of
the base assembly and one screw in the burner
area, rotate the clamping plate clockwise to
remove it.
(15)
The mounting plate assembly can then be
moved backward to gain access to the remaining parts in the control system.
(16)
From this view we can see the Printed Circuit
Board which controls the automatic heat
selection functions of the refrigerator and the
12 volt DC relay which energizes the 12 volt
DC heating element when the automatic
selection calls for 12 volt operation. To the
right of the DC relay is the igniter reigniter
module.
A-6-5
(17)
This component replaces the piezo lighter
that has been used on Dometic manually
controlled refrigerators for several years. When
the automatic controls select LP gas operation,
12 volts are sent to the igniter which produce
a high voltage to create a pulsating spark at
the burner. If for any reason the flame blows
out, the igniter will re-light the flame at the
burner.
(18)
To better understand how the first generation
series models operate, we will illustrate how a
typical RV family would use the refrigerator.
It is always recommended to pre-cool the
refrigerator before taking the RV on a trip to
gain the most efficiency from the unit. So, a
day or two before the customer plans to leave
on vacation the coach is plugged into 120 volts
shore power.
(19)
The customer then selects the desired
thermostat setting on the refrigerator. A
normal setting for the first generation series is
setting number 4, which will provide an
approximate lower cabinet temperature range
of 35 to 40 degrees.
(20)
Now, when the main rotary switch is turned
on, the refrigerator will automatically start
operating on the 120 volt AC cooling mode.
A-6-6
(21)
To let the customer know that the switch is
properly turned on and that there is sufficient
DC power to energize the system, L.E.D. lamp
will illuminate green.
(22)
After the refrigerator has reached the desired
cabinet temperatures, the customer then can
load the refrigerator with pre-chilled food.
(23)
When the RV family is ready to begin
travelling, coach’s owner disconnects the shore
line from the power source, which will
discontinue the operation of the 120 volt
heating element.
(24)
At this time the refrigerator’s controls will
automatically light the burner assembly and
the unit will be fully functional on the LP gas
mode. This automatic mode selection is
accomplished without the need to manually
reset the refrigerator. What could be easier?
A-6-7
(25)
When the driver gets in the vehicle and turns
on the ignition key, the gas flame will shut off
and the 12 volt heating element will be
energized to operate the refrigerator while
traveling.
(26)
This automatic switching to the 12 volt DC
heating element mode is accomplished by the
correct field wiring of the ignition lock
terminal on the rear of the refrigerator, which
we will discuss in further detail later in the
program.
(27)
When the vehicle’s ignition switch is turned
off when stopping to refuel, there is no need
to manually turn off the refrigerator to
prevent the g a s f l a m e f r o m l i g h t i n g .
Incorporated into the electronic controls is a
safety delay. This will prevent the burner from
lighting for approximately 25 minutes after the
ignition key is turned off.
(28)
After this delay time and the ignition key has
not been turned on or 120 volts has not been
supplied, the refrigerator will then re-light on
LP gas.
A-6-8
(29)
NOTE: The 120 volt mode is not affected by
the delay cycle. Any time the refrigerator is
supplied with 120 volts AC the unit will be
fully operational on the AC mode, even if the
refrigerator is in a delay cycle.
THE 120 VOLT MODE
IS NOT AFFECTED BY
THE DELAY CYCLE
(30)
After the customers have reached the campsite
and have parked the RV, they plug the 120
volt shore line into a power source. At this
point the unit will operate it’s ingrained
priority system.
(31)
The added benefit of this system is if the AC
power source is lost during a storm or the like,
the refrigerator will automatically switch to
the LP gas mode during the power failure. As
soon as the AC power is re-established, the
A.E.S. system will switch again to 120 volts.
(32)
Now that we have a basic understanding of
how a customer will use an A.E.S. refrigerator,
let’s take a look at some of the other features
incorporated into the control system. First, we
have the L.E.D. lamp assembly which will
provide the customer with useful information
in regard to the operation of the refrigerator.
A-6-9
(33)
As we stated earlier, in normal operation the
L.E.D. lamp will illuminate green.
(34)
On the LP gas mode, if a proper gas flame is
not established within approximately 3
minutes, the lighting sequence will shut off
and the L.E.D. will begin flashing red to warn
the customer that the refrigerator has failed to
light on LP gas. This does not always indicate
that the refrigerator is broken. It is simply a
warning device to let the customer know that
the refrigerator did not light due to a lack of
LP gas, that the burner is dirty or there is air
in the LP supply lines.
(35)
To reset the lighting sequence; turn the main
switch to the off position, wait approximately
5 seconds, then turn it back on. This will reset
the controls to provide another approximate 3
minute lighting period as well as to reset the
L.E.D. lamp to green. If, repeated attempts to
light the system fail, troubleshooting the LP
gas system is in order, which we will discuss in
the troubleshooting segment of the program.
A-6- 10
(36)
Second, the control system incorporates a low
battery protection circuitry that will prevent a
total lack of cooling due to a gradual loss of 12
volts DC to the refrigerator’s terminal block. If
the battery voltage to the terminal block drops
to approximately 9.5 volts DC and the
refrigerator is operating on 120 volts or LP
gas, the system will electronically bypass the
thermostat and the refrigerator will operate
continuously on LP gas until the low voltage
condition is corrected.
(37)
As a warning of this condition the L.E.D. lamp
assembly will shut off during the voltage drop.
When the battery voltage returns to an
acceptable level the green L.E.D. lamp will
turn on and the refrigerator will again operate
on its predetermined priority system.
A-6- 11
ON
GAS
FAILURE
SOLID
GREEN
FLASHING
RED
LOW
VOLTAGE
/OFF
NO LIGHT
(39)
The last feature that we need to discuss is the
operation of the thermostat on the LP gas
mode. Unlike the manually controlled models,
A.E.S. refrigerators do not have a high and
low flame to regulate the interior cabinet
temperatures. The high flame, that is present
after the lighting sequence, will shut off completely when the thermostat reaches the preset
temperature. The automatic controls will then
relight the burner when the thermostat calls
for cooling. This allows the refrigerator to
utilize the LP gas mode in a much more
efficient manner, very similar to the pilot-less
gas stoves that are now becoming quite popular.
(40)
The models that make up the second generation series A.E.S.
refrigerators include: the RM3500, RM3600 and RM3800. The RM
3500 being a 5 cubic foot refrigerator, the RM3600 being a 6 cubic
foot model and the RM 3800 being an 8 cubic foot refrigerator. The
function and operation of this model series is the same as the first
generation. The main difference with the second generation model
series is of parts relocation and decoration refinements. Let’s take a
look at these design differences.
(41)
From the upper front decoration we can see
that the switch L.E.D. lamp assembly is
located on the upper front exterior of the
refrigerator, making it easier to turn on and
off. The switch in this format uses a slider
verses the rotary version found on the first
generation models.
A-6-12
(42)
The L.E.D. lamp assembly contains two
separate diodes, one green and one red that are
an integral part of the switch.
(43)
From the interior of the refrigerator we can
see the thermostat-interior lamp assembly,
which is similar to the thermostat assembly
found on many residential type refrigerators.
(44)
The thermostat knob does not have the
numbered increments as found on the first
generation models. The markings of “MIN” and
“MAX” indicate the warmest and coolest
settings that can be obtained with the
assembly. As with previous thermostats,
rotating the knob clockwise will decrease the
lower cabinet temperature, while rotating it
counterclockwise will increase the lower
cabinet temperature.
(45)
From the rear we can see that the component
parts have been relocated directly on the rear
of the refrigerator. This allows better serviceability and lets us incorporate a new thinline base to provide the same cubic foot
interior, but shortening exterior cut-out
dimensions.
A-6-13
(46)
Here we see the cut-off valve and the printed
circuit board and its connections.
(47)
Next, we can view the igniter-reigniter, DC
relay and just below these components is the
LP gas solenoid valve. To the right of this is
the orifice-burner assembly.
(48)
The third generation series models include: the RM3601, a 6 cubic
foot refrigerator and the RM3801, an 8 cubic foot refrigerator. These
two models incorporate the latest technology in A.E.S. refrigerators.
They offer expanded functions and features that were not previously
available on the first or second generation series models. The general
construction and layout is very similar to the second generation
models.
(49)
From the rear we can see that the cut-off
valve, printed circuit board, igniter, relay,
solenoid valve and burner assemblies are in
similar locations as the second generation
series.
A-6-14
From the front there are two notable differences. The front upper decoration houses
the mode switches as well as the L.E.D. lamp
indicators that can give the customer useful
information on what mode the refrigerator is
operating on.
Inside the refrigerator is the t h e r m o s t a t
that contains the
redesigned thermostat knob.
interior lamp assembly
(52)
The knob is marked at the warmest setting
with letters MIN, which is an abbreviation for
minimum. The coldest setting is marked MAX,
which stands for maximum. In the central
portion of the knob is the normal temperature
range that the customer would utilize in most
situations. This portion of the knob is marked
NORMAL. Let’s take a few moments to discuss the third generation models in detail.
(53)
These refrigerators are equipped with a similar
type of automatic energy control system that
is found on both the first and second
generation models. In the fully automatic mode
the heat selection will be made electronically
with the highest priority going to the 120 volt
AC mode. The second priority will go to the
12 volt DC heating element when the vehicle’s
ignition switch has energized the ignition lock
terminal. The last priority is the LP gas mode.
AES ELECTRONIC PRIORITIES
1. 120 VOLTS A.C.
2. 12 VOLTS D.C.
3. L.P. GAS
A-6-15
(54)
The customer can manually select the controls
to operate on AC and LP gas only; again with
AC having priority over the LP gas mode or
the customer may select LP gas only.
When the main switch is turned on the
electronic control system will always select the
fully automatic mode. At this time the A.E.S.
pushbutton switch will illuminate green
indicating the system has selected the fully
automatic mode. As with the earlier A.E.S.
models the refrigerator will select between 120
volts AC, 12 volts DC or LP gas.
If the customer desires the selection to be
made only between 120 volts and LP gas, the
customer simply pushes the A C g a s
pushbutton. As soon as the button is energized
the A.E.S. lamp will shut off and the AC gas
pushbutton will illuminate green. This
indicates the refrigerator will select only
between 120 volts and LP gas, so that even
while the customer is traveling, and 12 volts
DC is available at the ignition lock terminal,
the unit will not operate the 12 volt heating
element. Instead, the system will select the LP
gas mode while traveling.
A-6-16
(57)
If the gas only pushbutton is depressed the
lamp will illuminate green and the refrigerator
will only operate on the LP gas mode, even if
120 or 12 volts are available.
q
(59)
Anytime the customer wishes to know what
source of heat the system is operating on, the
question mark button may be depressed. The
corresponding lamp will illuminate as long as
the question mark button is pushed. For
example, if the unit is operating on 120 volts
AC and the question mark button is engaged,
the AC lamp will illuminate.
If it is operating on the 12 volt heating
element mode, the 12 volt lamp will illuminate.
A-6-17
(61)
If the coach pulls into a gasoline station and
the refrigerator is in a safety delay, the clock
syymbol will illuminate.
(62)
Finally, if the unit is operating on LP gas, the
gas symbol will illuminate.
(63)
As with other A.E.S. models, the third
generation series has a flame failure indicator
that will illuminate red if the system fails to
light after approximately 3 minutes. This
flame failure indicator will illuminate within
10 seconds, however, if no spark is achieved at
the burner on the gas mode. A grounded electrode assembly may cause this condition. We
will discuss the diagnostic steps to correct this
situation in the troubleshooting section of our
program.
q
A-6-18
(64)
Another significant change in the third
generation A.E.S. system is how the 12 volt
heating element mode operates. As with the
first and second generation series, the 12 volt
heating element circuit is energized by the
ignition lock terminal. This terminal receives
its DC voltage from a wire that runs from the
run side of the vehicle’s ignition switch to the
refrigerator’s ignition lock terminal. This
allows the 12 volt heating element to be
energized only when the RV is traveling down
the road.
(65)
When the ignition lock terminal is energized
by the ignition key, the printed circuit board
must see at least 13.3 volts DC for a period of
40 seconds before the system will activate the
12 volt DC heating element.
TAG LINE ENERGIZED
VOLTAGE ---) 13.3 V.D.C.
(FOR 40 SEC. MIN.)
12V ELEMENT
ENERGIZES
(66)
If 13.3 volts is not achieved in this time frame,
the electronics will light the LP gas burner and
the refrigerator will operate on the LP gas
mode.
LOWER THAN 13.3 V.D.C. =
L.P. GAS
OPERATION
A-6-19
(67)
If at any time while traveling the DC voltage
reaches the approximate 13.3 threshold, the LP
gas flame will shut off and the 12 volt heating
element will energize, continuing normal
operation on the 12 volt mode.
TAG LINE ENERGIZED
VOLTAGE -+ 13.3 V.D.C.
(FOR 40 SEC. MIN.)
12V ELEMENT
ENERGIZES
(68)
The voltage to the terminal block is
continuously monitored by the printed circuit
board, while the RV is traveling. Let’s take a
look at a couple of ways this battery protection
system can be beneficial to the customer. First,
suppose a customer has a weak or underrated
alternator installed in the RV that is equipped
with an RM3801. As the vehicle’s ignition is
turned on, the ignition lock terminal is
energized by 12 volts, but because of the weak
alternator, the printed circuit board can never
see the 13.3 volts at the terminal block that is
needed to energize the 12 volt heating element.
So, the refrigerator will light and stay on the
gas mode while the RV is traveling.
TAG LINE ENERGIZED
VOLTAGE
13.3 V.D.C.
(FOR 40 SEC. MIN.)
12V ELEMENT
ENERGIZES
LOWER THAN 13.3 V.D.C.
q
L.P. GAS
OPERATION
(69)
After a few hours of driving, the customer
pulls into a gasoline station to refuel the
vehicle. Even though the system is operating
on the gas mode, as soon as the ignition key is
turned off, the LP gas flame shuts off and the
system initiates an approximate 25 minute time
delay mode. This allows the customer to stop
and refuel the coach without turning the unit
off. As long as the ignition lock terminal is
energized with 12 volts by the ignition switch,
the system will always go into a safety delay
when the ignition key is turned off. This will
prevent an open flame at the burner when
refueling.
,,’
VOLTAGE +
s”i”C:C~,N.)
12V ELEMENT
ENERGIZES
LOWER THAN 13.3 V.D.C. =
L.P. GAS
OPERATION
::..::.::.::
..:.,.:::,.::..
IGNITION KEY
TURNED DFF =
25 MIN.
SAFETY DELAY
A-6-20
(70)
Secondly, suppose a customer has a properly
wired RM3801 in a motor home that is
equipped with a fully functional alternator.
After the ignition key is turned on, the printed
circuit board determines that at least 13.3 volts
is available at the terminal block, so the 12
volt heating element engages.
TAG LINE ENERGIZED
VOLTAGE ---) 13.3 V.D.C.
(FOR 40 SEC. MIN.)
12V ELEMENT
ENERGIZES
(71)
When the customer leaves on the trip it is a
hot, muggy night so the vehicle’s headlamps as
well as the dash air conditioning system is
turned on. After a few minutes of driving it
begins to rain, so the windshield wipers are
also turned on. With all of these components
operating in the coach, the alternator has
difficulty keeping up with the demand of the
total coach load and the house battery begins
to drain. As soon as the printed circuit board
sees that the battery voltage going to the
refrigerator has dropped to approximately
volts, the electronic circuitry will shut off the
12 volt DC heating element to protect the
house battery, At this time, an approximate 25
minute delay cycle will be in progress.
LOWER THAN 11 V.D.C. =
HEATING
ELEMENT
OFF
(72)
If the battery voltage remains low after the
delay cycle, the automatic controls will light
the refrigerator on the LP gas mode and stay
on the gas mode until the printed circuit board
sees approximately 13.3 volts DC to the
terminal block.
SAFETY DELAY
LOWER THAN 13.3 V.D.C.
FOR 25 MIN. OR MORE q
L.P. GAS
OPERATION
A-6-21
(73)
If at any time the battery regains itself to the
approximate 13.3 volt threshold during the 12
volt cooling mode, the controls will again
reengage the 12 volt DC heating element.
TAG LINE ENERGIZED
VOLTAGE
13.3 V.D.C.
(FOR 40 SEC. MIN.)
12V ELEMENT
ENERGIZES
(74)
As with the first and second generation series
A.E.S. models, any time the battery voltage to
the terminal block drops to approximately 9.5
volts DC, the refrigerator will switch to a
nonthermostatically regulated gas flame to
insure the unit will still provide cooling for
the customer. As a low battery indication, the
green mode switch indicator lamp will shut
completely off during the voltage drop.
ON
SOLID
GREEN
(75)
Before we take a look at diagnostic procedures
for the A.E.S. refrigerators, let’s discuss the
external fuel and power source requirements
for proper operation. 120 VOLT AC POWER
- the refrigerator is equipped with a three
prong, grounded AC plug for protection
against shock hazards and should be plugged
into a p r o p e r l y g r o u n d e d t h r e e p r o n g
receptacle. Do not cut or remove the
grounding prong from this plug.
(76)
The power cord should be routed to avoid
coming in contact with areas that become hot
during normal operation or areas that could
create a safety hazard. These areas include the
burner cover, flue cover or the manual gas
shut-off valve knob.
A-6-22
LOW
VOLTAGE
/O F F
FLASHING NO LIGHT
RED
GAS
FAILURE
(77)
For proper cooling on the AC mode, the AC
voltage to the refrigerator should not vary
more than 10 percent from the voltage rating
on the heating element. Heating elements used
in Dometic refrigerators could have a rated
voltage of 110 volts, 115 volts or 120 volts AC.
Because of this, the power requirements for
each differently rated heating element will
vary. For example, if a heating element is
rated for 100 volts, the acceptable power range
would be between 99 to 121 volts AC. If an
element is rated for 115 volts, the acceptable
power range would be between 103.5 to 126.5
volts AC. If the heater is rated for 120 volts,
the acceptable AC power range would be
between 108 to 132 volts AC.
(see page A-6-24)
(78)
Refer to the voltage rating stamped on the
heating element to determine if the voltage to
the refrigerator is adequate to operate the
system properly.
(79)
12 VOLT WIRING - for any A.E.S. to operate
on any heat source the refrigerator must
receive a 12 volt supply to the positive and
negative connections on the terminal block at
all times. The refrigerator must be connected
directly to the house battery with 2 wires of
adequate capacity to avoid a voltage drop.
A-6-23
RATED VOLTAGE ON
HEATING ELEMENT
110V
115V
120v
AC OPERATIONAL RANGE
- 121VAC
99
103.5 - 126.5V AC
- 132VAC
108
A-6-24
As seen in the chart on page A-6-26, the
gauge of wire required to the positive and
negative connections on the terminal block will
depend on the size of the refrigerator and the
length of wire run from the house battery to
the terminal block. This 12 volt circuit must be
fused. The maximum fuse size should be 30
amps.
(see page A-6-26)
Be sure that a separate negative wire lead
coming directly from the battery is connected
to the negative terminal on the refrigerator
and that a frame or chassis ground is not used
as a substitute. Be certain that no other 12 volt
equipment or lighting is connected to the
refrigerator circuit. For the refrigerator to
operate properly on any heat source, the
terminal block must receive between 10.5 and
13.5 volts DC.
(see page A-6-27)
(82)
If any other technical information is needed
when diagnosing or repairing any 12 volt
circuit problem the technical data sheet can
give you other beneficial information, such as
heater wattages and amperage draws. (Refer
also to Service Bulletin 28).
(see page A-6-28)
(83)
Please note that if a battery converter is used
as the sole DC power source, the refrigerator
will not operate properly. The pulsating DC
power created by the converter will confuse
the electronic circuitry into erratic operation
and possible printed circuit board failure.
When a battery converter is utilized in the
installation, the circuit must be wired as shown
in the diagram on page A-6-29.
(see page A-6-29)
A-6-25
RECOMMENDED WIRE GAUGE AND LENGTH FOR
AES MODEL REFRIGERATORS
AWG
10
8
6
Maximum Wire Length
RM3500
RM663
19 ft.
31 ft.
49 ft.
RM3600
RM763
13 ft.
22 ft.
34 ft.
RM3800
RM1303
N/A
19 ft.
31 ft.
1st and 2nd generation series models.
AWG
10
8
Maximum Wire Length
RM3601
17 ft.
27 ft.
3rd generation models.
A-6-26
RM3801
17 ft.
27 ft.
REFRIGERATOR
TERMINAL BLOCK
POSITIVE
NEGATIVE
A-6-27
AES REFRIGERATOR TECHNICAL DATA
1ST GENERATION MODELS
MODEL
NO.
COOLING UNIT
PART NO.
ORIFICE SIZE &
PART NO.
RM 663
928 3609 00/7
52 (200 7419 18/3)
CORRECT
FLOW
METER
READING
.48
BTU INPUT
BURNER
1226
A/C Heater
HEATER E L E M E N T S P E C S . A C D C
Resistance
Watt/Volts , Part No.
AMPS AMPS IN OHM’S
Electric Thermostat
PART NO.
210/120
292 05210012
0173738 048
1.8
17.5
67
Gas Thermostat
PART NO.
0.522 00/2
2ND GENERATION MODELS
MODEL
NO.
COOLING UNIT
PART NO.
ORIFICE SIZE &
PART NO.
CORRECT
FLOW
METER
READING
BTU INPUT
BURNER
A/C Heater
HEATER ELEMENT SPECS. AC
DC
Resistance
Watt/Volt. , Put No.
AMPS AMPS IN OHM’S
Electric Thermostat
PART NO.
RM 3500
293 4701 09/1
3 9 (200 7419 IS/Q)
.48
1000
185/120
0173738 063
1.5
16.4
80
200 7712 OS/S
RM3600
293 4801 0 9 / 9
5 3 (200 7419 19/l)
.52
1300
295/120
0173754 046
2.5
17.9
48
293 0523 01/0
RM3800
293 4901 0 9 / 7
58 (200 741Q 2 1 / 7
.60
1500
325/120
0173742 081
2.7
17.9
44
293 0523 01/0
Gas Thermostat
PART NO.
200 7712 0 3 / 3
3RD GENERATION MODELS
RM 3601
293 4801 09/9
53 (2W 7419 19/l)
.52
1300
295/120
0175754 045
2.5
17.9
48
293 0814 01/3
293 0814 01/3
RM 2801
293 4901 0 9 / 7
68 (200 7419 21/7)
.60
1500
325/120
0173742081
2.7
17.0
44
293 0814 01/3
293 0814 01/3
A-6-28
,
PROPER WIRING OF AN AES WITH A BATTERY CONVERTER
00+
REFRIGERATOR
TERMINAL BLOCK
CONVERTER
12V BATTERY
A-6-29
(84)
If the 12 volt circuit is wired as shown on page
A-6-31, the battery will not be able to
properly filter the converter voltage. This
could cause erratic operation or premature
printed circuit board failure. Remember, the
positive and negative DC power leads to the
refrigerator must come directly from the
battery.
(see page A-6-31)
LP GAS SUPPLY - A.E.S. refrigerators use
liquid petroleum gas (propane) that is adjusted
to provide a pressure of 11 inches water
column pressure at the refrigerator test plug;
with at least l/2 of the coach’s LP gas load in
operation.
(86)
A periodic leak check of all the LP gas
connections
is recommended
using a
noncorrosive type o f b u b b l e s o l u t i o n .
WARNING: DO NOT use a flame to check for
leaks.
(87)
If, during the lighting sequence, attempts to
start the LP gas flame are not successful, make
sure the LP tank is not empty. Also, insure
that all of the manual shut-off valves are
turned on and are in the open position.
A-6-30
TERMINAL
STRIP
(Buss Bar)
\
REFRIGERATOR
TERMINAL BLOCK
UNACCEPTABLE CONNECTION FOR AN AES
A-6-31
(88)
If the refrigerator has not been used for some
time or if the main supply tanks have just
been refilled, air may be trapped in the LP
supply lines. To purge this air from the lines
may require resetting the refrigerator two or
three times before normal gas operation will
begin.
(89)
We will now take a look at the troubleshooting
procedures for the A.E.S. models RM3801 and
RM3601. For diagnostic information on the
first and second generation series models, refer
to Service Bulletin No. 46. (See pages A-9- 1 to
A- 10-2).
(90)
We will cover each of the four most common
service problems separately and illustrate the
steps needed to diagnose and repair the
refrigerator properly. These situations include:
NO operation, meaning the refrigerator will
not operate on 120 volts, 12 volts or LP gas,
NO 120 volt AC operation, 12 volt DC
operation, and NO LP gas operation.
DIAGNOSTIC AREAS
1.
NO OPERATION
2. NO 120 V.A.C. OPERATION
3. NO 12 V.D.C. OPERATION
4. NO L.P. GAS OPERATION
(91)
Whenever an A.E.S.
NO OPERATION.
refrigerator fails to operate on any heat source
we must diagnose the components and circuits
that are utilized by every heat source.
NO OPERATION
A-6-32
(92)
The first step to take is to insure that the 12
volt DC power supply and it’s associated
wiring is providing the proper DC voltage to
operate the electronic circuitry correctly.
Remember without a proper DC hookup to the
refrigerator’s terminal block, the unit will not
operate on any heat source.
(93)
Check the incoming battery voltage at the
terminal block to insure that between 10.5 to
13.5 volts are present and that the correct wire
polarity has been utilized in the installation.
REFRIGERATOR
TERMINAL BLOCK
(94)
Second, make sure the negative battery lead
connects to the negative connection on the
terminal block and the positive battery lead
connects to the positive connection on the
terminal block. As we stated earlier in the
program, check to see that the 12 volt
refrigerator circuit is wired as shown in this
diagram. Correct this if necessary. (Also see
page A-6-27).
RECOMMENDED WIRE GAUGE AND LENGTH FOR
AES MODEL REFRIGERATORS
AWG
(95)
Third, inspect that the proper gauge wire has
been used as illustrated in the chart shown
here. (Also see page A-6-26)
Wire Length
RM3500
RM3600
10
19 ft.
13 ft.
8
31 ft.
22 h.
6
49 ft.
34 ft.
s
l
1st and2nd generation “ti mode
8
27 ft.
3rd generation models.
A-6-33
RM3800
N/A
19 ft.
31 ft.
27 ft.
(96)
Check the 3 amp. DC fuse at the rear protection cover. If it is blown, check the 12 volt
wiring on the coach and refrigerator for
damage and repair, or replace if needed. When
replacing the 3 amp. fuse do not substitute
with an automotive quick blow type fuse, as it
could needlessly blow during normal refrigerator operation.
(97)
The next component to check in our diagnosis
is the thermostat. If the thermostat or
thermostat leads are defective the refrigerator
will not operate on any heat source, as all heat
sources are directed through this component in
normal operation.
(98)
If it is believed the thermostat circuit is
defective, first inspect the condition of the
thermostat cable and see that it is correctly
connected to the printed circuit board.
(99)
Next, gain access to the interior light
thermostat assembly by removing the
mounting screw and taking off the plastic
cover to expose the thermostat and wire
connections.
A-6-34
Remove the two thermostat leads and place
them together using electrical tape. This will
by-pass the thermostat from the electrical
circuit. If the refrigerator begins operating
when the leads are by-passed, the thermostat
is defective and must be replaced. Be careful
not to touch any surrounding metal parts with
the thermostat lead ends when performing this
procedure, as this will needlessly blow the 3
amp. protection fuse.
(101)
The main switch contains many different
functions in the A.E.S. refrigerators, which
includes controlling the heat sources. In this
section we will discuss the troubleshooting
procedures for the entire switch functions,,
including the mode switch lamps as well as the
function lamps. Before gaining access to the
switch, visually inspect the switch cable for
any cuts or shorts. Check to see that the plug
connector is properly inserted into the printed
circuit board connection.
(102)
Next, disconnect the positive and negative
battery leads from the terminal block. All of
our diagnosis on the switch will be made with
continuity or ohm’s resistance. Failure to
disconnect the DC power supply during
diagnosis could result in switch failure if it
inadvertently touches metal.
A-4-35
(103)
Refer to the RM3801 switch diagnosis
s e c t i o n o f the A.E.S.
troubleshooting
Diagnostic Manual for a detailed explanation
on how to troubleshoot these switches. (See
pages A-8-l to A-8-5)
(104)
The next component to diagnose is the
solenoid valve’s internal winding. The A.E.S.
control system uses the solenoid winding to
provide a ground circuit to the printed circuit
board for all modes of operation. If the
solenoid winding is defective, the refrigerator
will not operate on any heat source.
(105)
To check the solenoid winding, remove all
power sources from the refrigerator, AC and
DC and unplug the connector at the solenoid
by pulling firmly outward.
Measure the resistance value across the upper
and lower terminals on the valve assembly.
The proper valve should be 20 ohms with
tolerance range of 10 percent. Values outside
the tolerance range or no ohms reading would
indicate a defective solenoid valve winding.
A-6-36
(107)
As in all of our troubleshooting steps, the
printed circuit board is the last component to
check for a failure. Insure that all of the
connections on the board are clean and are
inserted in their proper locations before
attempting to determine if the printed circuit
board is at fault.
(108)
Many times when a circuit board failure is
noticed it will be visible as a burned section on
the board. Determine the cause of the board
failure by referring to SERVICE BULLETIN
R56-7A (pages A- 1 l-3 to A- 11-5) and correct
the external problem before replacing the
circuit board. FAILURE TO DO SO COULD
RESULT IN REPEATED BOARD
PROBLEMS.
(109)
NO 120 VOLT AC OPERATION. To begin
our diagnosis of the 120 volt mode, determine
if the house battery and its associated wiring
is adequate to operate the electronic circuitry
properly, as we discussed in the “no operation”
section of our program.
NO 120 V.A.C. OPERATION
Also, determine if the AC voltage to the
refrigerator is within 10 percent of the rated
stamped voltage on the heating element.
Correct any wiring or voltage problems as
needed to provide an adequate power supply to
the refrigerator.
A-6-37
(111)
After we have determined that the correct AC
and DC power is available to the refrigerator,
we need to diagnose the 120 volt heating
element. Generally speaking, when a 120 volt
heating element does not deliver the proper
amount of BTU’s, it does not heat up at all. In
some cases, however, a heating element may
be just partially defective. In either case, the
troubleshooting steps are the same to
determine if the element is at fault.
(112)
Remove the 120 volt power cord from the wall
outlet and gain access to the heater leads on
the printed circuit hoard by removing the
necessary protection covers.
(113)
Remove the leads and measure for proper
resistance across the two heater leads with a
properly calibrated ohm meter. Refer to
S E R V I C E B U L L E T I N 2 8 o r t h e AES
TECHNICAL DATA SHEET on page A-6-28
to determine if the ohms value obtained is the
proper reading for the model you are working
on.
(114)
Shown here is an example of the information
available in this bulletin. As with most of our
electrical checks, an acceptable tolerance range
on the ohms valve obtained is 10 percent. If
the ohms value on the heating element does
not fall within the necessary tolerances, the
element is defective and must be replaced.
A-6-38
(115)
Do not diagnose the heating element by
checking only for continuity. A continuity
check does not properly check the integrity of
the element. If a zero ohms reading is
indicated, an internal short is present in the
heating element. Heater replacement would
then be necessary.
DO NOT DIAGNOSE THE
HEATING ELEMENT BY
CHECKING
ONLY FOR CONTINUITY
(116)
At this time, also inspect the printed circuit
board for burned marks or damaged board
components using SERVICE BULLETIN R567
A(pages A-l l-3 to A-l l-5). Whenever
diagnosing
1 2 0 v o l t problems alwavs
remember to verify the heating element’s ohms
resistance. A shorted 120 volt heating element
can cause permanent printed circuit hoard
failure. (See pages A-l l-3 to A- 1 l-5)
(117)
After diagnosing the heating element, insure
that all of the connections on the module
board are inserted correctly and that there are
no damaged leads that could cause circuit
board failure.
A-6-39
(118)
Next, diagnose the switch by following the
switch diagnosis section of the A.E.S. manual
which we have previously discussed. As a final
check in our diagnosis of the 120 volt circuit,
visually inspect the refrigerator power cord. If
necessary check the cord end to end for
continuity on the ground black and white
wires that make up the power cord. If no
continuity is indicated on one or more of the
power cord wires replace the power cord.
During this diagnostic step be sure that the
power cord leads are firmly connected to the
AC terminal block.
(119)
NO 12 VOLT DC OPERATION.
As we
mentioned earlier in the program, the ignition
lock terminal houses the wire connection that
controls the 12 volt heating element circuit and
the 25 minute delay cycle.
The wire from this terminal should be routed
directly to the run side of the vehicle’s ignition
switch. This will provide DC voltage to the
ignition lock terminal only when the vehicle is
in motion. It also allows the vehicle’s alternator
to keep the house battery charged and
eliminates a possible dead battery due to the
customer forgetting to switch off the
refrigerator. Whenever the ignition key is
turned off, the electronic control system will
initiate a 25 minute delay cycle. When the
vehicle’s ignition is turned back on the system
will re-energize the 12 volt DC circuit. The
ignition lock wire, which is commonly
referred to as the “tag line”, should be a wire
size of at least 16 gauge. The amperage
demands from the element are handled by the
positive and negative leads of the terminal
block, which necessitates the need for larger
wire gauge requirements.
A-6-40
NO 12 V.D.C. OPERATION
(121)
When beginning to diagnose the heating
element circuit, keep in mind that an
approximate DC voltage of 13.3 to the
terminal block is required to engage to 12 volt
DC heating element. Any voltage lower than
13.3 will prevent DC operation and the
refrigerator will operate on the LP gas mode.
(122)
After verifying that the 12 volt battery circuit
is wired properly and that the proper gauge
wire size has been utilized. Check the DC
voltage at the terminal block to insure that at
least 13.3 volts is available to energize the 12
volt heating element.
(123)
If proper voltage is available at the terminal
block and the refrigerator is still not
operational on 12 volts, the DC relay needs to
be diagnosed.
(124)
Gain access to the relay and make sure the
ignition switch is turned to the off position
and voltage is not present at the ignition lock
terminal. DC voltage should be present
between terminals 85 and 30 on the relay. If
voltage is not present, recheck all 12 volt
connections. Pay close attention to the
connections on the positive terminal, as this is
where the 30 terminal attaches.
A-6-41
(125)
DC voltage should not be present between
terminals 85 and 87 on the relay when the
ignition key is disengaged. If voltage is present
at these terminals the relay is defective and
must be replaced.
Next, energize the vehicle’s ignition switch
and check for voltage between terminals 85
and 86 on the relay. Voltage should be present.
If no voltage is present between these
terminals, other components and connections
are suspect, such as the switch, thermostat or
circuit board.
As our final test of the relay, check for
voltage between terminal 85 and 87. If no
voltage is present the relay is defective and
must be replaced.
(128)
A defective 12 volt heating element will also
cause the refrigerator not to operate on the DC
mode. Disconnect the heater lead that attaches
to the 87 terminal on the DC relay and the
lead that attaches to the refrigerator grounding
strip.
A-6-42
(129)
Measure resistance across the leads as outlined
earlier in our program for the 120 volt heating
element. The reading, however, will be
different from the AC heating element. For
the models RM3601 and RM3801 the ohms
resistance should be .67, with a tolerance range
of 10 percent. If there is no ohms reading or a
reading outside the 10 percent tolerance range,
the heater is defective and must be replaced.
Please note that it will take a very precise ohm
meter to accurately read this measurement.
(130)
A malfunctioning switch assembly may also
affect the DC mode. As outlined in previous
diagnostic steps in our program, diagnose the
switch for proper operation. In our final check
of the 12 volt cooling system, check all wiring
harnesses and leads for shorts or opens. If
necessary use an ohm meter, end to end, on
the suspect leads.
(131)
NO LP GAS OPERATION
NO LP GAS OPERATION
A-6-43
(132)
To diagnose a gas operational problem be sure
the refrigerator is in the A.E.S. mode.
(133)
The first diagnostic step is to be sure there are
proper DC volts at the terminal block, in
accordance with the previous explanation on
the DC power source. (See pages A-6-33
through A-6-34, paragraphs 92-96)
(134)
Next, check to be sure the 120 volt power cord
to the refrigerator is unplugged from the
receptacle. Then check for voltage at the
terminal block between the ignition lock
terminal and the negative terminal. If any
voltage is present you will not be able to have
gas operation. These must be corrected before
any further checks can be done.
(135)
Now that we have proper DC voltage, no 120
volt and the ignition lock is not energized, we
can start to diagnose the gas system. Be sure
the manual gas shut-off valve is in the off
position. Remove the twelve (12) millimeter
gas test port plug and install a l/8 NPT fitting
in its place.
A-6-44
(136)
Now hook up a manometer to the test fitting
and leave it in place until all checks have been
made for gas operation. Turn the shut-off
valve and refrigerator on and check for a gas
pressure reading. A correct reading would be
eleven (11) inches water column pressure. If
needed, adjust the main gas regulator at the
LP gas tanks.
(137)
If you do not obtain any pressure, you must
check the electric solenoid. To diagnose the
electric solenoid windings, do the ohms
resistance check that was discussed earlier in
this program. (See page A-6-36, paragraph
106)
(138)
Another check is to disconnect the electric
solenoid wires. Supply DC voltage to the
BOTTOM terminal of the electric solenoid by
means of a temnorarv jumper wire from the
positive terminal on the terminal block.
A-6-45
(139)
You should hear a sharp click from the
solenoid and now obtain a gas pressure
reading. If these results are not realized the
solenoid is defective and must be replaced.
(140)
If these results are correct you must next
check the wires that connect to the solenoid
voltage. The results should be close to the
voltage coming to the appliance.
(141)
We will now check the igniter-reigniter
assembly. First turn the unit on and check for
voltage between the positive and ground
terminals on the igniter. If you obtain a DC
voltage reading, the igniter is receiving power.
(142)
If you do not obtain a reading, move the meter
probe from the ground terminal of the igniter
to the negative terminal on the terminal block.
If you now have a reading on the meter and
you did not at the igniter, you have a problem
in the ground circuit. If you obtained a
reading on both the tests, the igniter is
receiving power.
A-6-46
(143)
The next diagnostic step is to turn the unit off
and then remove the high voltage wire from
the igniter. When the unit is turned on you
should hear a sharp clicking sound from the
igniter. If no sound is detected, replace the
igniter. When sound is present the igniter is
good.
(144)
If the igniter checks good and there still is no
spark at the electrode, you must check the
high voltage wire and electrode. Make a visual
check of the high voltage wire for any defects
or broken insulation on the wire that could
allow the high voltage to go to ground. Also,
check the wire that has been disconnected at
each end for continuity.
(145)
The electrode spark gap must be set at three
sixteenths (3/16) of an inch to provide a
proper spark. The spark gap is the distance
between the burner and the tip of the
electrode.
Burne
(146)
You would next check the electrode for any
visual cracks or breaks on the ceramic portion.
If you have a good igniter and high voltage
wire and still do not have spark at the tip of
the electrode, replace the electrode.
A-6-47
(147)
A very important function of the igniter
assembly is to measure the condition of the
flame. The flame completes the high voltage
circuit and the spark stops when enough flame
is present.
(148)
If all of the diagnostic steps have been
completed with positive results and you are
still experiencing lack of cooling, be sure the
orifice, burner and flue tube have been
cleaned. To clean the orifice use an alcohol
based solvent and air. NEVER use a drill bit
or jet tip cleaner to clean any orifice, as these
devices will damage the factory machined part
and CREATE A POTENTIALLY
DANGEROUS SITUATION.
(149)
To properly clean the flue tube we would
suggest obtaining a flue brush. The part is
available through your local Dometic/DuoTherm distributor.
(150)
Now that we understand how to troubleshoot
and repair the A.E.S. controls, do not forget
that you must have the basics of proper heat,
ventilation and leveling for the absorption
cooling unit to operate effectively.
BASIC’S OF PROPER COOLING
UNIT OPERATION
HEAT
VENTILATION
LEVELING
A-6-48
(151)
If you require additional service assistance the
basic requirements for the cooling unit
operation or the A.E.S. control system, please
refer to our manual refrigeration or A.E.S.
training manuals. For day-to-day technical
service assistance contact the technical service
department.
(152)
You are an essential part of a team that
contributes greatly to the successful future of
the RV industry, your dealership and The
Dometic Corporation.
A-6-49
AES Refrigerator
GLOSSARY OF TERMS
Automatic Energy Selector Refrigerators. First introduced in 1983, the 1st and 2nd generation
series will automatically select the available heat source for operation (12OV AC, 12V DC or LP gas)
by simply turning the refrigerator to the “ON” position. The 3rd generation series have the added
flexibility of being utilized in three (3) individual selector switches, the refrigerator can be operated
as a full AES, on 120V and LP gas only or gas operation only.
AES
AUTOMATIC IGNITER/REIGNITER - An electronic 12V DC device that directly replaces the piezo
lighter, found on manually controlled models for several years. When 12V DC is supplied to the
igniter it produces a high voltage that is supplied through the electrode cable and electrode which
produces a spark at the burner to light the air/gas mixture. An added benefit of this system is that
12V is supplied continuously to the igniter during the gas mode. If the flame should blow out, the
igniter will re-engage and relight the flame at the burner. An additional function of the igniter is that
it produces an increased DC voltage that ultimately opens the solenoid valve.
BURNER - A slotted metal tube located just below the flue tube on the cooling unit, an integral part
of the gas system. This is where the igniter spark occurs which produces LP gas flame at the burner
that produces the necessary heat to initiate the cooling process at the cooling unit. Both orifice and
burner should be cleaned periodically to maintain proper cooling capabilities of the refrigerator.
DELAY CYCLE - If refrigerator is wired to the installation according to Dometic’s specifications, every
time the ignition switch is turned to the “OFF” position, following 12V cooling operation, a safety
delay cycle begins. For approximately 25 minutes the refrigerator will remain off and will not select
LP gas operation. This is to insure there will not be an open flame at the burner while the customer
refuels the R.V.. The 120V cooling mode is not affected by the delay cycle. Anytime the refrigerator
receives 120V at the power cord, the unit will operate on the AC mode. On the 3rd generation series
models this safety delay cycle has been incorporated into the controls to protect the 12V DC cooling
circuit as well. If battery voltage to the terminal block drops below 11V DC when the refrigerator
is operating in the 12V DC mode, the controls will disengage the 12V heating element and go into
a delay cycle. As soon as battery voltage regains proper voltage (13.3V DC) the delay cycle will
discontinue and refrigerator will operate on 12V DC cooling mode. If voltage does not regain itself
after approximately 25 minutes, the controls will select gas operation to insure proper cooling. This
delay cycle may be over-run (see Off/On Procedure, Item 24).
A-7-1
AES Refrieerator GLOSSARY OF TERMS continued
ELECTRODE - The angular piece of metal located just above the burner that is connected to the
high voltage cable. High voltage “jumps” the air gap between electrode and burner, and creates
the sparking seen at the burner. This circuit is grounded by the gas flame which stops the sparking
produced by the igniter. For igniter/high voltage cable/electrode assemblies to operate correctly,
the electrode must be positioned properly. The air gap distance between electrode and burner
should measure approximately 3 / 1 6 "
GAS PREVENTION SAFETY DEVICE - The AES has a safety circuit that will prevent sparking
and gas ignition on the gas mode if one of the following conditions occur:
A. Printed circuit board failure
B. Igniter failure
C. No voltage is present at positive and negative
connections at the terminal block
This safety circuit is designed to insure that LP gas will not accumulate at the burner due to a part
failure.
HEAT INPUT - One (1) of three (3) requirements for proper operation with absorption refrigerators.
This specification is critical to maintain proper cooling properties of the cooling unit. With too
little heat at heating element or burner, the ammonia in the cooling unit will not vaporize (boil
off) properly and a lack of cooling will result. An excessive amount of heat to the cooling unit will
cause the water, as well as ammonia, to vaporize, causing the cooling process to stop. Since as little
as 25 BTU’s input can dramatically affect operation of the cooling unit, it is NOT recommended
to substitute heating element sizes or burner orifice values. Whenever diagnosing heat input
problems, refer to Service Bulletin No. 28 or the AES Technical Data Sheet on page A-6-28.
HEATING ELEMENTS - Self-contained heat generating devices operating off either AC or D C
voltage that supplies heat to generator section of the cooling unit.
HIGH VOLTAGE ELECTRODE CABLE - Cable that transmits high voltage, produced by
igniter, and sends it to the electrode. High voltage from the igniter results in sparking at
burner assembly which lights the air/gas mixture at the burner. This cable should always
disconnected when diagnosing the igniter. If the cable is shorted to ground the result will be
spark on LP gas operation.
A-7-2
the
the
be
no
AES Refrigerator GLOSSARY OF TERMS continued
INDICATOR LAMP(S) - Consisting of light emitting diode(s) (L.E.D.) the 1st and 2nd generation
series refrigerators will illuminate green when main switch is turned to the “ON” position. If
refrigerator fails to ignite after trial for ignition sequence (2-3 minutes), the green L.E.D. will
shut off and a red L.E.D. will flash on and off, indicating a flame failure. If the incoming battery
voltage to the terminal block drops to approximately 9.5V DC, the indication lamp will shut off
indicating a low voltage situation. The 3rd generation series utilizes three (3) separate green
L.E.D.‘s that are located behind the mode selector pushbuttons. If this series goes into flame
failure, a separate L.E.D. will illuminate orange to indicate this condition.
LEVELING - One of three (3) requirements for proper operation with absorption refrigerators. The
absorption design utilizes no mechanical pumps or compressors to circulate the refrigerant within
the system, so proper leveling must be maintained to provide the correct refrigerant flow. Without
proper leveling, refrigerant within the cooling unit will collect and stagnate at certain areas.
Without proper refrigerant flow, the cooling process will stop. Cooling units that utilize an exposed
siphon pump tube at the generator section (units with square boiler boxes) require a precise
leveling check. To properly level these units a spirit (bubble) level is placed on the floor of the
freezer compartment. To insure operation with the refrigerator when the coach is positioned in
a stationary (standing) manner, the bubble must be at least 3/4 inside the central ring.
Important: Permanent damage can result to the square boiler box units if proper leveling is not
maintained. In recent years Dometic has engineered a new type of cooling unit that utilizes an
enclosed pump tube surrounded by a weak ammonia solution to protect the assembly. These units
are evidenced by a circular boiler box cover. To insure proper leveling in these units, the vehicle
needs to be leveled only so it is comfortable to live in (no noticeable sloping of floor or walls).
When the vehicle is moving leveling is not critical as the rolling and pitching movement of the
vehicle will pass to either side of level, keeping the ammonia from accumulating in the piping.
LP GAS TRIAL FOR IGNITION (Lockout) - Similar to a DSI R.V. furnace, AES refrigerators
incorporate a timed lighting sequence that is controlled by the printed circuit board. When the
controls select LP gas operation, high voltage sparking from igniter and LP gas solenoid are
energized. Normally in just a few seconds spark will ignite air/fuel mixture at the burner and
remain burning until thermostat is satisfied or refrigerator is turned off. If there is air in the gas
line, or the R.V. rig has not been used for a long period of time, this lighting procedure may take
up to 2 to 3 minutes to establish a flame. For this reason the AES refrigerator will attempt to light
the refrigerator for approximately 3 minutes. If after this timed sequence the refrigerator fails to
establish a flame, the igniter and solenoid valve will disengage and no longer attempt to light the
burner. This condition is referred to as lockout. To let the customer know that the refrigerator has
gone into lockout, on the 1st and 2nd generation series models, a red L.E.D. will “flash” on the
control strip on refrigerator exterior. On 3rd generation series models an orange flame failure
indicator will illuminate to identify this condition. Lighting procedure and flame failure indicators
can be reset by making an Off/On procedure.
A-7-3
AES Refrigerator GLOSSARY OF TERMS continued
MAIN SWITCH (1st Generation) - A rotary, two (2) position switch used to complete or interrupt
main power circuit to the printed circuit board. This switch utilizes an “OFF” and “ON” position
only. With switch turned “ON” the refrigerator will select and operate on the heat source available.
OFF-ON PROCEDURE - Any time the delay cycle is not desired it may be overridden by turning
the main switch to the “OFF” position, waiting approximately 5 seconds and then turning the
switch back “ON”. This procedure cancels the printed circuit board’s “memory” and refrigerator
will relight on LP gas within a few seconds.
POLARITY - The property of voltage that causes electrons to flow through a circuit in a certain
way. In a 12V DC circuit electrons flow from the negative connection on the battery, through the
interconnecting wiring and circuits, then back to the positive connection on the 12V DC battery.
Because of this property, to insure proper operation of the refrigerator, the negative lead, from
the battery, must be connected to the negative connection on the refrigerator terminal block. The
positive lead from the battery must be connected to the positive connection on the terminal block.
PRINTED CIRCUIT BOARD (PCB) - Sometimes called a module board, this device controls many
of the operational sequences in the AES refrigerator. The board has three (3) primary functions
including:
A. Controlling all heat sources (12OV, 12V & LP gas)
B. Monitors incoming battery voltage from terminal block
C. Controls the approximate 25 minute delay cycle from 12V DC operation to LP gas operation.
RELAY. 12V DC - A component controlling the circuit to the 12V DC heating element. Containing
a set of normally open contacts, the relay will complete the circuit (by closing contacts) to the
heating element when proper voltage is established at the relay. With proper voltage supplied to
the relay, an internal coil is energized which closes the contacts to enable 12V DC heating to
operate.
SWITCH BOARD (CARD) (2nd Generation) - Similar to the rotary switch found on 1st generation
AES models. The circuits are housed on a printed circuit “bread” board that includes a slide switch
and two (2) indicator L.E.D.‘s. Although appearance and diagnosis of this switch is slightly
different from the 1st generation switch, it functions the same in the electrical circuit.
A-7-4
AES Refrigerator GLOSSARY OF TERMS continued
SWITCH/MODE INDICATOR BOARD (3rd Generation) - A more sophisticated version of the
switch board. This switch assembly has three (3) separate pushbutton switches as well as the
On/Off main slide switch. The three (3) pushbutton switches are marked a
n
d
When
the
main
switch
is
turned
on,
the
3rd
generation
refrigerators
will
c l
mode, operating very similar to the 1st and 2nd generation series.
automatically select the
This mode of operation will be indicated by the button illuminating green. If AC and LP gas
pushbutton may be depressed.
pushbutton will illuminate
only is desired, the
to indicate this mode selection. If gas only operation is desired, the
pushbutton may be
depressed. Regardless of what heat source is available, the refrigerator at this point will only
pushbutton will illuminate to indicate this mode selection.
operate on LP gas. Again, the
If a flame failure occurs, the L.E.D. assembly will illuminate orange at the lens
This assembly also provides useful information to indicate what mode of operation the
electronic circuitry has selected. On the switch panel there are four (4) indication lenses
marked
,
,
andl. Wh enever it is desired to determine what mode of operation the
AES has selected, the small mode indication button
is depressed. While this button is
will illuminate
depressed and the AES circuit has selected the 11OV AC mode,
yellow. If refrigerator has selected 12V DC operation the
lens will illuminate while mode
will illuminate yellow if system is in the approximate 25
indication is depressed. The
minute delay cycle. Finally, if gas selection has been made, the
lens will illuminate.
q
q q q
q
q
q
TERMINAL BLOCK (MAIN) - The AES utilizes a three (3) section terminal block instead of the
two (2) section assembly found on 3-way manually controlled refrigerators. The block houses
connections marked positive (+), negative (-) and ignition lock (ign. lock). A wire of proper gauge
is connected from the positive lug on the battery to the positive connection on the terminal block.
A similar wire, again of proper gauge, is connected from the negative lug on the battery to the
negative connection on the terminal block. This gives the printed circuit board a power feed to
automatically select the proper heat sources and handles the amperage demands when the
refrigerator is operating on 12V DC cooling mode. A minimum 16 gauge wire is connected from
the run side of the ignition switch to the ignition lock connection on the terminal block. This wire
connection will allow the refrigerator to switch to the 12V DC cooling mode when ignition is
turned to the “ON” position. When the ignition key is turned “OFF” (directly after 12V operation)
the refrigerator will go into an approximate 25 minute delay cycle (see Delay Cycle).
THERMOCOUPLE - A component connected to solenoid valve, extending above the burner assembly
so tip is in the path of flame when refrigerator is operating on LP gas mode. When heat is
generated at the tip, the thermocouple will produce a small amount of DC voltage that will keep
the solenoid mechanism open to sustain flame. If the flame should blow out and igniter cannot
relight flame within a few seconds, the tip of the thermocouple will cool, which will interrupt the
production of voltage that, in turn, will allow the mechanism of the solenoid to close. This will
prevent LP gas from accumulating at the burner. The thermocouples used will produce from 14 30 millivolts DC in normal operation.
A-7-5
AES Refrigerator GLOSSARY OF TERMS continued
THERMO-ELECTRIC SOLENOID VALVE - This device directly replaces the safety valve assembly
found on the manually controlled refrigerators. When the AES selects LP gas operation, 12V DC
is sent to the solenoid which opens the internal valve. This allows gas to flow onto the test plug
and burner assemblies. Once flame is lit, DC millivolts, produced by thermocouple, will keep the
valve open. If for any reason the reigniter cannot reestablish flame, the thermocouple will cool
which will stop production of DC millivolts. At this time the solenoid valve will close preventing
LP gas to accumulate at the burner.
THERMOSTAT - Very similar to electric thermostats found on the manually controlled refrigerator
models. This thermostat operates off 12V DC and regulates the inside refrigerator temperature on
all heating modes by making and breaking the heat source circuit to the printed circuit board. If
thermostat is broken (bellows relaxed) on any AES, the refrigerator will not operate on any heat
source.
VENTILATION - One of the three requirements for proper cooling unit operation. The coach vent
system must be able to provide a way to direct the hot air produced by the action of the cooling
unit out away from the installation of the refrigerator. The refrigerator extracts heat (cooling)
from the interior of the refrigerator cabinet and dissipates the heat out through the vent system.
The vent area must be free of dead air pockets surrounding the sides and top of the refrigerator
to achieve proper air flow. The smaller size refrigerators utilize a double side wall vent system.
Where the incoming air is drawn through the lower vent and the heat is dissipated through the
upper vent. The larger size refrigerators use a lower side vent and roof vent to accomplish the
same venting requirements. The size and placement of each of these vents is critical so it is
important to refer to the specific vent requirements outlined in the installation manual when
diagnosing vent systems.
VOLTAGE MONITORING 12V DC (PCB) - The printed circuit board has the ability to monitor
incoming battery voltage to the terminal block. On the 1st and 2nd generation series models, if
battery voltage drops to approximately 9.5V DC (on 120V & LP gas modes only) the printed
circuit board will electronically “by-pass” the thermostat circuit causing refrigerator to light on
gas and stay on continuously regardless of thermostat knob setting. This is to insure the customer
will not lose cooling due to voltage drop. When the voltage drop occurs the green L.E.D. will
completely shut off to warn customer of low incoming voltage. Third generation series models
have an even more sophisticated 12V DC monitoring system. These models will not engage the 12V
DC heating element circuit until 13.3V DC is detected at the terminal block for approximately 40
seconds. If proper voltage (13.3V DC) is not established within 40 seconds the printed circuit
board will select LP gas operation. If the 12V DC circuit to the heating element is initially
completed but, due to demands of all DC appliances in the R.V., the DC voltage drops to
A-7-6
AES Refrigerator GLOSSARY OF TERMS continued
approximately 1lV DC, the refrigerator will disengage the 12V heating element and initiate an
approximate delay cycle. (See Delay Cycle). As with the 1st and 2nd generation models, the 3rd
generation models will stay lit continuously on LP gas mode if voltage drops to approximately 9.5V
DC. At this time the mode switch lamp will shut off to let the customer know DC voltage is low.
WIRE GAUGE (Size) - A standardized method of rating the size of wire diameter. In electrical
appliances the size of wire is a necessary consideration so the circuits do not experience voltage
losses and the wire can handle the amperage demands of the electrical components. A small gauge
wire cannot safely handle the same amperage loads with a voltage drop that a larger gauge wire
can. The smaller the gauge of wire, the larger is its numeral value; the larger the gauge of wire,
the smaller is its numerical value. For the refrigerator to operate properly on all modes of heat,
refer to wiring size chart to insure the proper size wire has been used in the installation (see page
A-6-26).
A-7-7
AES Refrigerator
CONTINUITY READINGS FOR SWITCH CARD & HARNESS
Model 3801
The following is a list of checks that should be made on the switch card and harness assembly before
replacing the switch card or wiring harness. These checks are to be done with wiring harness
REMOVED from the printed circuit board.
1. ON-OFF SWITCH
A. With the switch in the “ON” position, continuity should be indicated between the yellow
terminal on the 10 pin connector to the orange terminal on the 10 pin connector.
B. With the switch in the “OFF” position, no continuity should be indicated between the yellow
terminal on the 10 pin connector to the orange terminal on the 10 pin connector.
C. With the switch in the “OFF” position, continuity should be indicated between the red
terminal on the 10 pin connector to the orange terminal on the 10 pin connector.
D. With the switch in the “ON” position, no continuity should be indicated between the red
terminal on the 10 pin connector to the orange terminal on the 10 pin connector.
2. AES FUNCTION SWITCH
A. With the AES function switch manually depressed, continuity should be indicated between
the blue terminal on the 7 pin connector to the black terminal on the 7 pin connector.
B. With the AES function switch NOT depressed, no continuity should be indicated between
the blue terminal on the 7 pin connector to the black terminal on the 7 pin connector.
3. AES FUNCTION LAMP
A. Measure resistance between the brown terminal on the 10 pin connector to the brown
terminal on the 7 pin connector. The proper resistance is approximately 65,000 OHM S .
4. AC/GAS FUNCTION SWITCH
A. With the AC/GAS function switch manually depressed, continuity should be indicated
between the blue terminal on the 10 pin connector to the orange terminal on the 10 pin
connector.
B. With the AC/GAS function switch NOT depressed, no continuity should be indicated
between the blue terminal on the 10 pin connector to the orange terminal on the 10 pin
connector.
A-8-1
AES Refrigerator CONTINUITY READINGS FOR SWITCH CARD & HARNESS continued
5. AC/GAS FUNCTION LAMP
Measure resistance between the brown terminal on the 10 pin connector to the gray terminal
on the 10 pin connector. The proper resistance is approximately 65,000 O H MS.
6. GAS FUNCTION SWITCH
A. With the gas function switch manually depressed, continuity should be indicated between
the violet terminal on the 10 pin connector to the orange terminal on the 10 pin connector.
B. With the gas function switch NOT depressed, no continuity should be indicated between the
violet terminal on the 10 pin connector to the orange terminal on the 10 pin connector.
7. GAS FUNCTION LAMP
Measure the resistance between the brown terminal on the 10 pin connector to white terminal
on the 10 pin connector. The proper resistance is approximately 65,000 OHMS.
8. 120V MODE LAMP SWITCH
A. With the mode switch (?) manually depressed, resistance should be indicated between the
brown terminal on the 10 pin connector to the red terminal on the 7 pin connector. The
proper resistance is approximately 2 1,000 OHM S.
B. With the mode switch NOT depressed, no resistance should be indicated between the brown
terminal on the 10 pin connector to the red terminal on the 7 pin connector.
9. 12V MODE LAMP AND SWITCH
A. With the mode switch manually depressed, resistance should be indicated between the brown
terminal on the 10 pin connector to the orange terminal on the 7 pin connector. The proper
resistance is approximately 2 1,000 OHM S.
B. With the mode switch NOT depressed, no resistance should be indicated between the brown
terminal on the 10 pin connector to the orange terminal on the 7 pin connector.
A-8-2
AES Refrigerator CONTINUITY READINGS FOR SWITCH CARD & HARNESS continued
IO. DELAY MODE LAMP AND SWITCH
A. With the mode switch manually depressed, resistance should be indicated between the brown
terminal on the 10 pin connector to the yellow terminal on the 7 pin connector. The proper
resistance is approximately 2 1,000 OHM S.
B. With the mode switch NOT depressed, no resistance should be indicated between the brown
terminal on the 10 pin connector to the yellow terminal on the 7 pin connector.
Il. GAS MODEL LAMP AND SWITCH
A. With the mode switch manually depressed, resistance should be indicated between the brown
terminal on the 10 pin connector to the green terminal on the 7 pin connector. The proper
resistance is approximately 21,000 OHM S.
B. With the mode switch NOT depressed, no resistance should be indicated between the brown
terminal on the 10 pin connector to the green terminal on the 7 pin connector.
12. GAS FLAME WARNING LAMP
Measure resistance between the brown terminal on the 10 pin connector to black terminal on the
10 pin connector. The proper resistance is approximately 21,000 OHM S.
NOTE:
In normal operation, the gas flame warning lamp will illuminate if the refrigerator fails to
light after approximately 3 minutes. This lamp, however, will illuminate within
approximately 10 seconds if the refrigerator fails to spark in the gas mode.
A-8-3
AES Refrigerator CONTINUITY READINGS FOR SWITCH CARD & HARNESS continued
Model 2802
The following is a list of checks that should be made on the switch card and harness assembly before
replacing the switch card or wiring harness. These checks are to be done with the wiring harness
REMOVED from the printed circuit board.
1. ON-OFF SWITCH
A. With the switch in the “ON” position, continuity should be indicated between the yellow
terminal on the 10 pin connector to the orange terminal on the 10 pin connector.
B. With the switch in the “OFF” position, NO should be indicated between the yellow terminal
on the 10 pin connector to the orange terminal on the 10 pin connector.
C. With the switch in the “OFF” position, continuity should be indicated between the red
terminal on the 10 pin connector to the orange terminal on the 10 pin connector.
D. With the switch in the “ON” position, no continuity should be indicated between the red
terminal on the 10 pin connector to the orange terminal on the 10 pin connector.
2. AC/GAS FUNCTION SWITCH
A. With the AC/GAS function switch manually depressed, continuity should be indicated
between the blue terminal on the 10 pin connector to the orange terminal on the 10 pin
connector.
B. With the AC/GAS function switch NOT depressed, no continuity should be indicated
between the blue terminal on the 10 pin connector to the orange terminal on the 10 pin
connector.
3. AC/GAS FUNCTION LAMP
Measure resistance between the brown terminal on the 10 pin connector to the gray terminal
on the 10 pin connector. The proper resistance is approximately 65,000 OHMS.
4. GAS FUNCTION SWITCH
A. With the gas function switch manually depressed, continuity should be indicated between
the violet terminal on the 10 pin connector to the orange terminal on the 10 pin connector.
A-8-4
AES Refrigerator CONTINUITY READINGS FOR SWITCH CARD & HARNESS continued
B. With the gas function switch NOT depressed, no continuity should be indicated between the
violet terminal on the 10 pin connector to the orange terminal on the 10 pin connector.
5. GAS FUNCTION LAMP
Measure resistance between the brown terminal on the 10 pin connector to white terminal on
the 10 pin connector. The proper resistance is approximately 65,000 OHM S.
6. GAS FLAME WARNING LAMP
Measure resistance between the brown terminal on the 10 pin connector to the black terminal
on the 10 pin connector. The proper resistance is approximately 2 1,000 OHM S.
In
NOTE:
normal operation the gas flame warning lamp will illuminate if the refrigerator fails to
light after approximately 3 minutes. This lamp, however, will illuminate within
approximately 10 seconds if the refrigerator fails to spark in the gas mode.
A-8-5
Operation of the AES System (Automatic Energy Selector)
The control system on the AES selects the most suitable energy source. The selection
will be made with highest priority to 120 volt, second priority to 12 volt from the
alternator (if 12V DC is provided to the ignition lock terminal from the vehicle ignition
switch) and lowest priority to gas operation. There are only two customer controls to
operate the system; the thermostat and the on-off switch.
When the switch is turned
on, a green indicator light glows to show that the system has 12 volts supplied. This
indicator light will flash red on the gas mode, if the propane burner fails to light.
The AES has a built-in safety device that delays gas ignition and start up approximately
20 minutes from 12 volt operation. This enables the customer to stop and refuel the
vehicle without touching the refrigerator. If the delay is not desired after stopping, the
system may be re-set by switching the main switch off and then back on.
SAFETY DEVICE
The AES system also has a built-in safety device that will prevent operation, if one of
the following parts breaks down: A. the printed circuit board, B. the igniter or, C. there
is no control voltage to the terminal block.
This feature ensures that the thermoelectric solenoid valve will not open as the result of a part failure.
FIG. 1
A - Printed Circuit Board
B - Igniter
C - Terminal Block
D - Electrode
E - Thermo-Electric Solenoid Valve
PART EXPLANATION AND TROUBLESHOOTING DIAGNOSIS
PRINTED CIRCUIT BOARD
From this point, all the energy
The printed circuit board is the heart of the AES.
120
sources are controlled, including the gas start-up delay from 12 volt operation. The
Anytime the system receives
volt operation is not affected by the 12 volt delay feature.
120 volts, the refrigerator will switch over to the 120 volt electric mode. It should be
noted, however, if the 120 volt supply is disconnected within the 20 minute delay cycle,
As before, if a delay is
a gas start-up will not occur until the end of the delay period.
A normal
not desired, the refrigerator may be re-set by making an off-on procedure.
gas start-up will then occur.
A-9- 1
Bulletin #46 continued
The circuit board on the AES also has the ability to monitor the 12 volt supply voltage.
If the incoming voltage to the refrigerator drops below 9.5 (+- 1) volts, the AES will
switch to gas operation and the refrigerator will be unaffected by the thermostat.
Until
the low voltage situation is corrected, the system will remain on gas continually and will
not switch to 120 or 12 volt and overcooling or freezing will probably occur.
As a
warning device. the green indicator light will shut off during the voltage drop. When
the incoming voltage returns to 12 volts, the green indicator lamp will switch back on
and the refrigerator will again return to the most suitable energy source.
It must be
remembered that the AES requires 12 volts at all times to operate on 120 volts, I2 volt
or gas.
When a problem with the refrigerator system is being diagnosed and it is suspected that
the circuit board is at fault, most likely the failure will be visible on the board itself.
If the AES fails to operate and it is noted that there is a shorted wire between diodes
or a shorted or burned section of the connecting foil on the circuit board, it is probable
that this circuit board is defective. Be sure the troubleshooting steps outlined below are
followed BEFORE changing the board. The AES Analyzer (Part #800-0006-00/0) also may
be used to test the printed circuit boards.
HEATERS
MODEL
OHM’S READING
3800 & 1303 AES
42 Ohm’s
3600 & 763
54 Ohm’s
3500 & 663 AES
82 Ohm’s
The 120 and 12 volt heaters that are included in the AES refrigerator contain a quick
These plugs are polarized and will fit
connect contact plug - for ease of replacement.
only one way. When checking the electric element, you should notice a 42 ohm’s reading
with the 3800 and 1303 AES; 54 ohms on the 3600 and 763; and 82 ohms on the 3500 and
663 AES. With these models on 12V operation, the heaters will draw 22.9, 20.8 and 15.8
amps respectively.
SOLENOID VALVE
The AES uses a thermo-electric solenoid valve for opening
and closing the gas supply line instead of the usual
manually operated safety valve. When the refrigerator is
ready to light on gas, the circuit board will send 12 volts
to the solenoid valve to open it. After the flame is lit
the millivolts supplied from the thermocouple will keep
FIG. 3
the solenoid valve open. The 12 volt signal current from
the circuit board will drop off in IO-20 seconds after the
flame is lit. To check the valve for operation, disconnect
the braided cable plug from the solenoid valve. Connect a
12 VOLT SOLENOID VALVE
jumper wire from the 12 volt positive terminal on the
refrigerator to the lower lug on the solenoid valve. When
this is done, an audible click should be heard. This
indicates that the valve is operational. The solenoid valve should be replaced if it does
not click open. If the valve opens, the D.C. voltage from the igniter must be checked.
T O open the solenoid valve, there must be a positive pulse voltage between the yellow
wire on the igniter (marked L) and ground. This pulse voltage is supplied by the
igniter. It should be noted that the resistance cannot be checked across the terminals When
the solenoid valve without damaging the circuit board if the braided cable is connected.
A-9-2
Bulletin #46 continued
The thermostat used in the AES system is a normal
electric thermostat without an off position.
It operates
on low voltage from the printed circuit board.
If the
thermostat is broken and has lost its charge, the
refrigerator will not operate on gas, 120 or on 12 volt.
If it is believed that the thermostat is broken, by-pass
the thermostat by removing the two wires connected to
it.
Then place t h e t w o l e a d s f r o m t h e t h e r m o s t a t
together and try for operation. The thermostat should be
replaced if the refrigerator now functions properly when
the leads are connected.
Overfreezing will occur in the refrigerator if the thermostat capillary tube is not far
enough into its holder. For the Model 1303 AES, the capillary tube distance should be
35” to 36” from the tip of the sensing tube to the bottom of its holder; and on the
Model 763 AES, it should be 31” to 32”.
For the new style thermostat, Part
No. /
9
AES, the capillary tube attaches to the evaporator on models 3800,
3600, 3500 and 663 ONLY.
IGNITER
HIGHVOLTAGE
GAS IGNITER
The igniter operates with 12 volt current. On gas
operation the igniter senses the resistance through
the flame between the electrode and burner.
When
there is no flame at the burner, the resistance is
high and the igniter begins sparking to light the
burner.
As soon as the flame is lit, the resistance
between the electrode and burner drops and the
igniter stops sparking. The resistance is monitored by
the igniter and if for any reason the flame goes out,
the igniter begins sparking until the burner is lit.
This insures that the flame will always be lit when
desired.
If the electrode does not spark, first make sure the igniter is receiving 12 volts. If the
igniter is receiving 12 volts and produces no spark, it must be checked for operation.
Remove the wire between the electrode and igniter and place 12 volts at the 12 volt +
It is important to
lug. If no internal clicking sound is heard, the igniter is broken.
remove the high voltage wire that goes to the electrode from the igniter when you are
The high voltage wire and the electrode can be
checking the igniter for operation.
connected to ground causing the circuit board to think that the flame is lit, resulting in
no spark on gas operation. Moisture or dirt on the electrode itself will also affect the
igniter. When diagnosing an igniter problem double check it to make sure the igniter is
dry, clean and has proper gap (see FIG. 7).
INDICATION LAMPS
The indication lamp consists of two light emitting diodes; one green and one red. When
the 12 volt supply to the refrigerator is adequate to operate the system, the green light
shows. If the system runs out of propane fuel, the indicator light flashes red to warn
you that the gas supply is depleted. If the battery voltage drops below 9.5 (& 1) volts,
the green indicator light will shut off to warn you of the low battery condition. At this
It also
time, the flame will be continuously lit until the battery returns to 12 volts.
must be remembered that all electrical connections in the AES are polarized, including
This light will show constant red and flashing green if it is
the indicator lights.
inserted upside down on the 1303. 763 and 663.
A-9-3
Bulletin #46 continued
MAIN SWITCH
ON/OFF SWITCH
RM1303, 763, 663
Models 1303, 763 663:
The switch operates on 12 volts from the circuit board. In normal operation, the switch
should travel only to the ON and OFF positions. A switch that travels more than this
has been installed incorrectly or the installation nut that holds the switch in place has
worked loose.
If the switch is the suspected point of failure, check the connecting
ribbon cable for visible cuts or shorts.
The switch can be checked for continuity
between terminals 1 and 2, 4 and 5, 6 and 7 in the “ON” position; and 2 and 3, 5 and 7
in the “OFF” position.
Remember to disconnect the switch from the AES circuit board
when checking for continuity.
Models 3800, 3600 3500:
Check for continuity only between terminals 1 and 2, 3 and 4, 5 and 10 using the low
scale (RX-l) on an ohm meter, with the switch in the ON position and continuity only
between terminals 1 and 3, 5 and 6 in the O F F position. Also, be sure to disconnect
from the AES circuit board and check continuity from the plug at the AES circuit board
end. This will check the ribbon cable as well as the switch.
ELECTRODE
FIG. 7
Spark Cap = 3/16" (Allen wrench
used for gas pressure
test fitting may be
used as a feeler gauge)
The electrode serves two basic functions on the AES refrigerator.
It is used as a
contact point to transmit the spark from the igniter to the burner. The electrode also
acts to measure the resistance between it and the burner and sends this information to
the igniter module. When the resistance is high, the igniter starts sparking and when it
Because of this, the electrode position is extremely
is low the igniter stops sparking.
important. If the electrode is too close to the burner the resistance is low and the
In this
system will think the burner is lit - especially true with high humidity.
situation, no spark will o c c u r . Some atmospheric conditions such as very high humidity
and/or coastal salt air may necessitate a wider than minimum gap; therefore, the optimum
gap should be 3/16" or 5 mm. If the gap from the electrode to the burner is too large,
the resistance will be too high and the igniter will continue to spark even though the
With this situation, the flashing red indicator light will come on in
flame is lit.
approximately 3 minutes.
A-9-4
Bulletin #46 continued
In closing, there are two more external parts that can cause problems with your AES
refrigerator. First, if your propane supply to your
refrigerator is depleted, no cooling
on gas will take place and the red indicator light will flash. When it is noticed that the
indicator light is flashing red, always check your fuel supply first. The second external
part that may be causing the problem with the control system is the 12 volt battery. If
a weak or dead battery is used to operate the refrigerator, the AES controls will not
function properly. N O cooling or bad cooling on gas, electric and 12 volt will occur, if
the battery is discharged or shorted.
If the battery drops below 9.5 (+- 1) volts, the
It has also been noted that the AES will
refrigerator will only be operational on gas.
often overcool with a weak battery in line. No indicator or interior light and no control
functions indicate a weak or dead battery. Remember, without a constant 12 volt source
to the refrigerator, the system will not work on 120 or 12 volt or on gas.
Some corrosion on the circuit boards resulting in malfunctions have been caused by water
or car wash solution being sprayed onto the back of the refrigerator through the side
Sealing the circuit board enclosure should prevent recurrence;
vent door louvers.
however, the owner should be made aware of this situation.
If you run into any problems that are not addressed here, please contact our Technical
Services Department available to all Dealers, Service Centers and OEM's.
A-9-5
AES REFRIGERATOR WIRING DIAGRAMS
6RM 6
3
CIRCUIT B o a r d
R E L A Y
Terminal
Blcok
HEATER
CONNECTORS
MAIN SWITCH
G A S F L A M E Warn. Lamp
@
@@
I@-
THERMOSTAT
GAS VALVE COIL
Thermocouple
Reignitor
WHITE
Black
@-- G R E E N
RM763
A-10-1
AES REFRIGERATOR WIRING DIAGRAMS
RM1303
@
CIRCUIT B o a r d
RELAY
TERMINAL Block
HEATER
CONNECTORS
@)- MAIN S W I T C H
@ G A 5 F L A M E Warn. Lamp
R M 3500 - RM3600 - RM3800
H
10 F
E
IO G
+--i-Q
J
10
to
u
T
S
U
C I R CU IT B O A R D
RELAY
TERMINAL BLOCK
HEATER
CONNECTORS
MAIN SWITCH
GAS FLAME WARN
FUNCTION L A M P
DOOR SWITCH
LIGHT
T HE R M O S T A T
GAS VALVE COIL
T HE R M O C O U P L E
REIGNITOR
T I M E FU S E 3-3.15
W H I T E - AWG I 3
- .
BLACK
GREEN
- ’
A-10-2
LAMP
AMP
AREA
18
24
CIRCUIT BOARD DIAGNOSIS
6
/
1.
IF THIS LEAD IS DAMAGED:
LOOK FOR A SHORT CIRCUIT OR DAMAGE IN
THE INTERIOR LIGHT CABLE.
2.
IF THIS LEAD IS DAMAGED:
LOOK FOR A SHORT CIRCUIT OR DAMAGE IN
THE RIBBON CABLE TO THE MAIN SWITCH
AND THERMOSTAT.
3.
I F T H I S C O M P O N E N T I S DISCOLORED, BURNED OR BLOWN:
CHECK ALL CABLES IN THE 12 VOLT SYSTEM
FOR SHORT CIRCUITS.
4.
I F T H I S C O M P O N E N T I S DISCOLORED, BURNED OR BLOWN:
CHECK THAT THE 12 VOLT CONNECTIONS ARE
CORRECT AND THAT THERE IS A BATTERY
BETWEEN ALTERNATOR AND REFRIGERATOR.
5.
I F T H I S LEAD(S) I S D A M A G E D :
CHECK FOR PROPER RESISTANCE IN OHM’S
OF THE A/C HEATING ELEMENT AND ALL
120 VOLT CABLES FOR SHORT CIRCUIT OR
DAMAGE.
6.
IF THIS COMPONENT IS DISCOLORED, BURNED OR BLOWN:
CHECK FOR PROPER POLARITY OF GAS
SOLENOID LEAD.
7.
IF THIS COMPONENT IS DISCOLORED, BURNED OR BLOWN:
CHECK FOR PROPER PLUG CONNECTIONS OF
GAS SOLENOID AND THERMOSTAT ON CIRCUIT
CHECK FOR SHORT CIRCUIT OR
BOARD.
DAMAGE IN RIBBON CABLE TO INDICATOR
LIGHT, THERMOSTAT.
A-ll - l
ometicl
quality leisure line productr
AUTOMATIC ENERGY SELECTOR
Our technicians continue to get calls from the field regarding the
flashing red light on the A.E.S. Refrigerators indicating a lack
of understanding.
There can be times when the red light may flash, but there is nothing
that has malfunctioned in the refrigerator.
In order to help our
customers make that determination, the following sequence is suggested.
1. Turn knob "A" (Main Switch) to position OFF.
Wait 5 seconds and
turn back to ON.
The indicator light "E" should go to green and
the control system will begin a new sequence.
If the-refrigerator
has not been in operation for a while or the gas bottles have just
been refilled, this operation may have to be repeated several t i m e s
to clear air from the gas line.
(Each gas starting sequence will
last for about 3 minutes).
2. If the above question is not successful, check your gas supply,
make sure that ALL gas valves between the refrigerator and the gas
bottles have been opened.
Don't overlook the gas shut off valve
" a " in the back of the refrigerator.
3. Make sure the R.V. Battery is not discharged as the refrigerator
can not function properly if the 12 Volt D.C. power is low.
4. If none of the above operations are successful, advise the customer to bring the unit in for diagnosis.
B
FIGURE B
FIGURE A
RE: Page 7, DSC #304,
Refrigerators
A
Installation and Operating Instructions, AES
A-II-2
Replacement of Circuit
3-WAY AES CIRCUIT BOARDS
RM3500,3600,3800
3
When working on an AES style refrigerator and
replacing the circuit board, the old board should
be visually inspected for any obvious damage,
i.e. burned components, damaged leads, burned
connectors, corrosion, etc.
When the board is damaged, see the illustration
to the left for what to check and correct before
changing the circuit board.
The following paragraph numbers relate to the
corresponding numbered items highlighted at the
circuit board.
-3
1.
If this component is discolored, burned
or blown: Check that the 12V connections
are correct and that there is a battery
between alternator and refrigerator.
2.
If this component is discolored, burned
or blown:
Check for proper polarity of
gas solenoid lead.
- 4
\5
A-ll-3
If this component is discolored, burned
Check all cables in the 12V
or blown:
system for short circuits.
4.
If this component is discolored, burned
or blown: Check for proper plug connections of gas solenoid and thermostat
c i r c u i t o r d a m a g e i n ribbon cable to
indicator light, thermostat.
5.
Check for
If this lead is damaged:
proper resistance in Ohm’s of the A/C
heating element and in all 12OV c a b l e s
for short circuit or damage.
6.
If these leads (dotted in the picture) at
t h e r e a r o f t h e b o a r d a r e damaged:
Check for proper resistance in Ohm’s of
t h e A / C h e a t i n g e l e m e n t a n d a l l 12OV
cables for short circuit or damage.
Bulletin #R56/7A continued
3-WAY AES CIRCUIT BOARDS
RM3501,3601,3801,4801
Check the old circuit board before installing a
new one. If damages as shown below are found,
the defects causing the circuit board breakdown
must be corrected before the new one is installed.
The following paragraph numbers relate to the
corresponding numbered items highlighted at the
circuit board.
/I
2
1.
If these areas are burned, the lead
between the circuit board and the
control circuit board must be checked
for short circuits.
2.
If soldering at board rear is burned, the
interior light lead is likely to be shorted
to ground.
3.
If RI1 is blown the “Ignition Lock”
voltage has been too high (over 12V
DC f 10%).
4.
If X5A, X5B, X5C, X5D
burned (either side of
AC voltage has been
12OV A C + 1 0 % ) .
heater in this case.
5.
If V12 is burned, the solenoid leads can
be reversed.
1
J3
.2
a n d / o r K1 a r e
the board), the
too high (over
Also check the
Bulletin #R56/7A continued
2-WAY AES CIRCUIT BOARDS
RM2602 AND RM2802
Check the old circuit board before installing a
new one. If damages as shown below are found,
the defects causing the circuit board breakdown
must be corrected before the new one is Installed.
The following paragraph numbers relate to the
corresponding numbered items highlighted at the
circuit board.
If this area is burned, the lead between
the c i r c u i t b o a r d a n d t h e c o n t r o l
circuit board must be checked for
short circuits.
If soldering at board rear is burned,
the interior light lead is likely to be
shorted to ground.
If X5A, X5B, X5C, and/or K1 are burned
(either side of the board), the AC
voltage has been too high (over l2OV
AC +- 10%). Also check the heater in
this case.
/’
2
- 1
-
-
1
2
A-ll-5
4.
If V12 is burned, the solenoid leads can
be reversed.
REPLACEMENT OF CIRCUIT BOARDS
Models:
RM663
RM1303
RM763
Refrigerator
Bulletin R58/7A
April 1987
When replacing the circuit board in the 663, 763 and 1303, you
install the 12 Volt DC fuse provided. See Item #2, Page 2.
Rev.
5/87
M U S T , upon inspection of the b o a r d ,
When working on an AES style refrigerator and replacing the circuit board, the old board
should be visually inspected for any obvious damage, i.e. burnt components, damaged leads,
burnt connectors, corrosion, etc.
1.
a.
When the board is damaged, see the following illustrations for what to check and correct
before changing the circuit board:
FIG. 1
The following paragraph numbers relate to the same indicator numbers at the ci rcuit board
desi gnations.
Look for a short
1. If this lead is damaged:
circuit or damage in the interior light cable.
2.
3.
4.
Look for a short
If this lead is damaged:
circuit or damage in the ribbon cable to the
main switch and thermostat.
If this component is discolored, burned or
blown: Check all cables in the 12 volt system
for short circuits.
If this component is discolored, burned or
Check that the 12 volt connections
blown:
are correct and that there is a battery between
alternator and refrigerator.
A-11-6
5. If this lead(s) is damaged: Check for proper
resistance in Ohm’s of the A/C heating
element and all 120 volt cables for short
circuit or damage.
6. If this component is discolored, burned or
Check for proper polarity of gas
blown:
solenoid lead.
7. If this component is discolored, burned or
Check for proper plug connections
blown:
o f g a s solenoid and thermostat on circuit
board. Check for short circuit or damage in
ribbon cable to indicator light, thermostat.
Bulletin #R58/7A continued
b.
Verify that the positive (+) 12V. DC wire going to the circuit board is connected directly
to the coach battery positive (+) terminal.
VEHICLE
ENGINE
FIG. 2
2.
The electrical system should also be checked to assure the 12V. DC circuit has been fused; if
not, see the following procedure:
Install the 12V. DC in-line fuse holder before the circuit board as shown in the illustration.
One-quarter of an hour labor is authorized to install the fuse along with the standard
time approved to install the circuit board.
FIG. 3
.I
.
j
(1.A BS. UNIT
@
C I R C U I T BOARD
@- RELAY
@ TERMINAL BLOCK
HEATER
CONNECTORS
@--- MAIN SWITCH
GAS FLAME WARN. LAMP
THERMOSTAT
($-- GAS VALVE COIL
@ THERMOCOUPLE
@- REIGNITOR
@- WHITE
BLACK
e GREEN
NOTE:
(1) Install the 3.5 Amp fuse here for the 12V. DC line protection.
A-l1-7
Bulletin #R58/7A continued
Lastly, the moisture shield kit has been enclosed and can be installed to prevent corrosion
damage caused by water or car wash solution being sprayed into the back of the refrigerator
The circuit board compartment should be sealed in the following
through the vent louvers.
manner:
a.
b.
Install the shield under the bottom mounting bracket of the cooling unit. See the drawing
below by model number. Seal the top edge with the foil tape supplied.
Seal around the conduit, where it goes into the circuit board compartment, with putty
tape supplied or a silicon sealant can be used.
FOIL TAPE
ALONG TOP
Model 7 6 3
\
Model 663
NOTE: The earlv series only w h i c h h a s t h e
enclosure,
requires
rectangular
boiler
that the shield be bent across the middle
slightly (I), with a little more angle on
the upper tab (2).
Models with the interior light conduit
(3) coming out of the top of the circuit
board housing may require a trimmed
slot and putty tape around the conduit
and slot.
Caution should be used when washing the vehicle
and avoid spraying water onto the refrigerator.
A-11-8
q
AES MODELS RM3601 3801
MODULEBOARDREPLACEMENT
Refrigerator
Bulletin R59/7A
May 1987
NOTE: Please t a k e full consideration of the following
information BEFORE replacing module boards d u e
to faulty 12 volt cooling operation.
This Bulletin clarifies the 12 volt DC start-up and cooling
operation.
FIG. 1
Each time the tag line is energized and 12 volt cooling is
selected, the module board must receive approximately 13.6
volts for about 40 or more seconds.
A t t h a t t i m e the
unit will engage the 12
volt heating element.
If
the initial
required
13.6
volts is not achieved (due
to demands of other 12
volt devices) the AES will
to
12
volt
not switch
operation, and will operate
instead on L.P. gas until the
13.6 volt threshold is reached.
If during 12 volt cooling, supply voltage should drop below
approximately 11.6 volts (FIG. 2), the DC cooling will shut
down and the AES system will go into a 25 minute delay (FIG.
3). This allows the supply voltage to re-establish itself.
FIG. 2
To view the delay, push the button identified with a question
mark
and the clock indicator light a will come on.
q
NOTE: If 13.6 volts is not recovered during the delay the AES
system will then switch to gas operation until the supply voltage
If during the 25 minute delay the 13.6 threshold
recovers.
voltage is recovered, the delay will be deleted and 12 volts DC
cooling will resume.
AES CONTROL PANEL ON REFRIGERATOR
FIG. 3
IGN
LOCK
-----
with all AES refrigerators, minimum voltage for a n y
operation is 10.5 volts DC at the terminal block.
As
+
FIG. 4
A-l1-9
D U O- TH E R M
1
(PRE-
PDI
D E L I VE R Y
INSPECTION)
PDI insures safe operation of Dometic Refrigerators. The following checks on each unit are advised before being operated by
the consumer. If each refrigerator is inspected according to
these guidelines, you can be assured of peak performance from
your Dometic refrigerator.
GREEN
OFF/ON
SWITCH
....
RM3500
RM3600
RM3800
3-Way
RM1303
..........
O
ON
.......................
....
F
F
........
ON
. . ...*
. . . . ...* . . . . . . .
...... .......
3-Way
2-Way
RM3501
RM3601
RM3801
RM2602
RM2802
A-II-10
Bulletin #R60/7A continued
AES
PRE-DELIVERY CHECK FOR
MODEL RM1303 AES REFRIGERATOR
This refrigerator is equipped with an Automatic
Energy Selector System.
The selection will be
made with the highest priority to 120 volts;
second priority to 12 volts from the battery if
the ignition is turned on; and with the lowest
priority to gas operation.
I. Supply 12 volts to ignition lock terminal at
rear of refrigerator, or start engine.
Flame
should go out
J. Remove 12 volt from ignition position.
unit should now be in a gas delay.
delay should be approximately 20 minutes.
The
This
K OVER-RIDE DELAY
1. Turn ON/OFF switch from ON to OFF,
wait approximately 5 seconds and turn
back ON.
OPERATIONAL TESTS
2.
A. Have 120 volt supply available
L. I f t h e a b o v e t e s t s a r e p e r f o r m e d w i t h o u t
fault, the AES is operating properly.
B. Make sure you have a good 12 volt battery
supply.
C. Make sure gas valves at tank and rear of
refrigerator have been turned on.
NOTE:
D. Turn ON/OFF switch to ON (bottom right
front of refrigerator.
E. Set thermostat to setting above #4 (second
knob from right).
F. Connect 120 volt supply.
light should be on.
The burner should re-light in approximately
15 seconds.
Green indicator
G. Check boiler box to see if it is warming up.
CAUTION: This area becomes extremely
hot and can cause burns.
H. Disconnect the 120 volt supply at rear of
The AES unit
refrigerator compartment.
Check burner
should go to gas operation.
box to see if flame is lit.
A-11-11
FLASHING RED LIGHT: This indicates
the unit tried to light on gas and
It is possible the unit had air
failed.
in the lines. Reset the controls.
Make sure the AES is wired directly to
battery with 30 amp breaker within 18
inches of battery.
Bulletin #R60/7A continued
AES
PRE-DELIVERY CHECK FOR
MODEL RM3500, RM3600, RM3800
NOTE: The above model numbers are upgraded
versions of the AES system.
Normal operation will be the same as
first generation.
The units will have
the following changes: Switch, Thermostat
and Light.
4. The refrigerator is equipped with a thermostat
which is located inside the cabinet on the
front of the light fixture.
/
LIGHT BULB
DOOR SWITCH FOR
INTERIOR LIGHT
1. The ON/OFF switch is located at the top right
side of the refrigerator.
2. The first light to the right of the ON/OFF
switch is the green light. When the ON/OFF
switch is in the ON position, this light will
be green.
3. The second light to the right of the ON/OFF
switch is the FLAME FAILURE light. This
will flash if the unit fails to light on gas.
OFF/ON
SWITCH
GREEN
;F&;ATIONAL
KpLlKt
A-l1-12
THERMOSTAT
KNOB
5. T h i s i s r e g u l a t e d b y t u r n i n g t h e k n o b t o
different settings in order to obtain desired
The closer the knob
cabinet temperatures.
is set to maximum, the lower the temperature.
Bulletin #R60/7A continued
AES
PRE-DELIVERY CHECK FOR
MODELS RM3601 AND RM3801
1. The AES automatically selects the best energy source for the situation, either 120 volts, 12
volts or LP gas.
2. This unit will also let you select the energy source you want.
3. Pictured below is the AES control panel that is found on this generation of AES refrigerators.
C
B
A
D
EFGHJ
K
AES CONTROL PANEL ON REFRIGERATOR
A.
Push button, green indicator - Full AES operation.
B.
Push button, green indicator - Limited AES operation:
120 volts or LP gas (priority to 120 volts).
C.
Push bottom, green indicator - LP gas operation only.
D.
Main switch - Push right, to turn unit ON. Push left to turn unit OFF.
E.
Yellow indicator - 120 volt operation mode.
F.
Yellow indicator - 12 volt operation mode.
G.
Yellow indicator - LP gas delay mode.
H.
Yellow indicator - LP gas operation.
I.
Question mark - push button.
operation,
J.
Flame Failure indicator - Indicates unit tried to light on LP gas and failed.
When pushed this button will indicate which mode is in
E-F-G or H.
OPERATIONAL TEST
6. Connect 120 volt supply to unit.
Make sure you have a good 120 volt supply
available.
You must also have a good 12 volt supply.
7. When switch “D” is set to ON, the AES
button will light up (green), indicating that
the control system is in the automatic mode.
In this mode 120 volts A/C has priority.
Be sure all LP gas valves have been turned
on, those at LP tanks and at rear of refrigerator.
Now
8. Push the question mark button “J”.
yellow indicator “E” (A/C) should light up.
Turn ON/OFF switch “D” to the ON position.
D
OFF
J
ON
A-ll-13
E
Bulletin #R60/7A continued
9. When switch "B" is pushed, the control system
will select only between 120 volts A/C and
LP gas operation.
To check, push question
mark button “J”.
Indicator light “E” should
light up.
B
[AC/n 1
E? = AC
cl
-;
-
Wait 5 seconds, then switch back to ON.
Flame failure indicator will go off, and system
will start another cycle for ignition.
K
-
IO. To check gas operation of switch “B”, remove
120 volt supply from rear of refrigerator.
Flame
Push switch “J” (question mark).
indicator should light.
This light will come on when
13. Indicator “G”.
The AES system goes
engine is turned off.
into a delay cycle which prevents LP gas
operation for 25 minutes. This is a refueling
If the engine is started during
precaution.
the delay cycle, 12 volts will resume and the
delay period will be reset to 25 minutes.
This means every time the engine is turned
off, you will have a complete 25 minute delay.
G
1 1. When switch “C” is pushed the refrigerator
will operate only on LP gas, even if 120 volt
A/C or 12 volt DC is available.
To check gas operation of switch “C”:
Push
Flame indicator light “H”
question mark “J”.
should now light.
C
h
I
H
?=n
i5
El-
This indicator
12. Indicator “K ” flame failure.
will light only when there has been a flame
failure in the LP gas operation mode. To
restart gas operation, set switch “D” to OFF.
A-l1-14
NOTE: Each time tag line is energized and
12 volt cooling is selected, the
module board must receive approximately 13.6 volts for 40 or more
At that time the unit will
seconds.
engage the 12 volt heating element.
If initial 13.6 volts is not achieved
(due to demands of other 12 volt
devices in the vehicle), the AES will
not switch to 12 volt operation and
will operate instead on gas until the
13.6 volt threshold is achieved.
As with all AES refrigerators, minimum
voltage for any operation is 10.5
volts DC at the terminal block.
Bulletin #R60/7A continued
FREEDOM SERIES
RM
2802
(PDI) PRE-DELIVERY INSPECTION
PDI insures safe operation of Dometic refrigerators. The following
checks on each unit are advised before being operated by the consumer.
If each refrigerator is inspected according to these guidelines, you
can be assured of peak performance from your Dometic refrigerator.
1. ORANGE continuous light: Indicates gas ignition failure - no gas.
2. MAIN SWITCH
3. PUSH BUTTON: Green - indicates gas operation ONLY.
4. PUSH BUTTON: Green - Gives energy selection between A/C and Gas.
NOTE: No 12 volt power selection possible.
OPERATIONAL TEST
3.
A. Have 120 volt A/C supply available.
1
B. Be sure you have a good 12 volt battery supply.
C. Make sure gas valves, both at tank and rear
of refrigerator, have been turned on.
E. Set thermostat to “NORMAL” position.
Plug coach 120 volt cord into 120 volt
outlet.
2.
Green A/C flame light #4 should be on.
refrigerator
this is not
3 minutes,
come on.
To correct this turn main switch OFF
and the back to ON. The green A/C flame
light should come on again.
D. Turn ON/OFF switch to “ON” position.
1.
Disconnect 120 volt cord. The
If
should now light on gas.
accomplished in approximately
the Flame Failure Light will
4.
4
To check GAS ONLY operation, push #3,
The system will
Green Flame Light.
then operate on gas regardless if 120 volt
If unit fails to light,
power is present.
Flame Failure Light will come on. Turn
OFF main switch and then turn back to
ON. Unit should now be lit on GAS.
3
AC
A-l l-15
GENERAL INFORMATION
FOR MODELS RM2602 & RM2802
The refrigerator is equipped with an
energy selector system.
The system
selects t h e m o s t suitable available
energy source. The selection will be
made with the highest priority to 120
volts and the lowest priority to gas
operation.
Once the low voltage has been corrected, the control system goes back
to normal operation.
To indicate
that the control system is in a low
DC voltage condition the selector
mode
[ A/C GAS ] indicator will be turned
off. The interior light is unaffected
during the entire procedure.
If the gas mode is chosen, the unit
will operate on gas only, even if 120
volts are present.
If the refrigerator does not succeed
in lighting on gas the first time,
turn unit OFF and then ON since
there might be air in the lines.
The control system always requires
12 volts DC to be able to operate
on ANY energy mode.
Below 9.5
volts DC the control system will go
to gas with no thermostat control.
A-12
AES REFRIGERATOR DIAGNOSTIC
SERVICE MANUAL
OS1160-A
Description
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Title Page
Notes
Table of Contents
Notes
AES Refrigerator Diagnostic Flow Chart / No Operation
AES Refrigerator Diagnostic Flow Chart / No 120V AC Operation
AES Refrigerator Diagnostic Flow Chart / No 12V DC Operation
(Checks AES Mode Only)
AES Refrigerator Diagnostic Flow Chart / No Gas Operation
AES Refrigerator Diagnostic Flow Chart / No Gas Operation
(continued)
Operation and Diagnosis - Dometic AES Refrigerator
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
OS1160-A AES Refrigerator Diagnostic Service Manual (continued)
Description
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Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
Operation and Diagnosis - Dometic AES Refrigerator (continued)
AES Refrigerator Glossary of Terms
AES Refrigerator Glossary of Terms (continued)
AES Refrigerator Glossary of Terms (continued)
AES Refrigerator Glossary of Terms (continued)
AES Refrigerator Glossary of Terms (continued)
AES Refrigerator Glossary of Terms (continued)
AES Refrigerator Glossary of Terms (continued)
3801 AES Refrigerator Continuity Readings for Switch Card &
Harness
3801 AES Refrigerator Continuity Readings for Switch Card &
Harness (continued)
3801 AES Refrigerator Continuity Readings for Switch Card &
Harness (continued)
2802 AES Refrigerator Continuity Readings for Switch Card &
Harness
2802 AES Refrigerator Continuity Readings for Switch Card &
Harness (continued)
Bulletin #46 Operation of AES System
Bulletin #46 (continued)
Bulletin #46 (continued)
Bulletin #46 (continued)
Bulletin #46 (continued)
AES Refrigerator Wiring Diagram RM663 & RM763
AES Refrigerator Wiring Diagram RM1303 & RM3500, 3600 &
RM3800
Bulletin #51 Circuit Board Diagnosis
Bulletin #53 Automatic Energy Selector
Bulletin R56/7A Replacement of Circuit Board
Bulletin R56/7A (continued)
Bulletin R56/7A (continued)
Bulletin R58/7A Replacement of Circuit Board RM663, RM763,
RM1303
Bulletin R58/7A (continued)
Bulletin R58/7A (continued)
Bulletin R59/7A AES Models 3601-3801 Module Board
Replacement
Bulletin R60/7A AES PDI
Bulletin R60/7A (continued)
Bulletin R60/7A (continued)
Bulletin R60/7A (continued)
Bulletin R60/7A (continued)
Bulletin R60/7A (continued)
General Information for Models RM2602 & RM2802
Notes
AES Refrigerator Diagnostic Service Subscription Order Form
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