Sea Frost 372 ROUTE Specifications

Sea Frost 372 ROUTE Specifications
372 ROUTE 4 BARRINGTON, NH 03825 USA
TEL (603) 868-5720
FAX (603) 868-1040
E-Mail:[email protected]
1-800-435-6708
www.seafrost.com
OPERATION & INSTALLATION
INSTRUCTIONS
BG 2000
404a SERIES
C.F. HORTON & CO., INC.
372 ROUTE 4
BARRINGTON NH 03825
U.S.A.
(603) 868-5720
WWW.SEAFROST.COM
SEA FROST is a registered trademark of C.F. Horton & Co., Inc.
Aspects of the SEA FROST design are covered by
US Patent # 4,356,708
Copyright © 2001 by C.F. Horton & Co., Inc.
TABLE OF CONTENTS
BG 2000 OPERATION
ICE MAKING
MAINTENANCE
HOW REFRIGERATION WORKS
INSTALLATION
SWAGELOK FITTINGS
CONDENSING UNIT LOCATION
VALVE
PUMP INSTALLATION
THERMOSTAT
RFD
ACCESS TO THE SYSTEM
GAUGES
LEAK CHECKING
NEW SYSTEM CHARGING
READING THE SIGHT GLASS
CHECKING THE CHARGE / ADDING CHARGE
TROUBLESHOOTING
SPECIFICATIONS
ACCESS PORT LOCATION (DWG)
WATER CIRCUIT (DWG)
SINGLE ZONE (DWG)
BG2000 110-VOLT WIRING
BG2000 220-VOLT WIRING
THERMOSTAT CALIBRATION
MARCH PUMP DESCRIPTION
4
5
6
8-9
10
11-13
14
15
16
17
17
19
20
22-23
22-23
25-26
26-27
28-30
31
32
33
34
35
36
37
39
NOTICE OF RESPONSIBILITY
It is the SEA FROST/ C.F. Horton & Co., Inc. intent to provide the safest, most accurate
and detailed instructions. SEA FROST/ C.F. Horton & Co., Inc. cannot be responsible
for problems or damage caused by omissions, inaccuracy or interpretations of these
instructions.
2
372 ROUTE 4 BARRINGTON, NH 03825 USA
TEL (603) 868-5720
E-Mail:[email protected]
FAX (603) 868-1040
1-800-435-6708
www.seafrost.com
A VIEW OF THE FUTURE:
As a once wonderful invention, refrigerants are now the latest enemy as our awareness
of the universe increases. To the end regarding conservation we have always offered a
leak proof system. We have also always designed our systems to operate with the
lowest quantity of refrigerant. We are concerned.
There is a global impact from all refrigerants and it is time now to address the concept
of "invisible pollutants".
Your new R-404a system has little environmental impact that we know of at this time.
This not to say those millions of tons of refrigerant won't make some problem in the
future. We must enjoy the benefits of refrigeration but be conscious of the
maintenance of the machinery to avoid unnecessary leaks and waste. Everyone must
be involved.
Thank you for supporting our product. We are proud to be providing what we feel is the
best equipment available, bar none.
Cleave Horton
3
BG 2000 OPERATION
The SEA FROST BG 2000 system is an electrically driven refrigeration plant. Operation
of the compressor will freeze the contents of the holdover devices in the boat's icebox
providing refrigeration by cold holdover for an extended period after the compressor has
been turned off. A boat without continuous power can benefit from this by operating the
SEA FROST BG 2000 system when the generator plant is operated. Operation time will
vary with each boat.
A little time-spent learning about your system and some experimentation will be best.
Maximum holdover will be reached when the cabinet is at the desired temperature and
the holdover plates are frozen. Running times beyond this have no advantage other
than to delay warming the plates.
The system is water-cooled. Water should begin to flow from the discharge at the same
time the unit starts. Be sure the water is flowing. If no water flows, stop the system and
inspect the water pump and strainer for obstructions. (See "Troubleshooting" and
"Maintenance" sections.)
After starting a warm system check the plates for a temperature drop. If a temperature
drop is not indicated, stop the unit and read; "Checking The Charge", and; "Reading
The Sight Glass".
CONTROLS
The BG 2000 thermostat control is labeled with "off", one, two, and three snowflakes.
When the boat’s breaker panel is switched on and AC power is available, turning the
knob from "off" to one snowflake will start the compressor. Turning the knob to three
snowflakes will increase the time the compressor operates, making the temperature
cooler. Experiment with the control position to obtain the best setting.
4
ICE MAKING
Your SEAFROST holdover plate may be equipped with vertical ice trays. The ice trays
are held in contact with the plate by a stainless steel rod.
Fill the vertical trays with water and hang them on the face of the plate. Try to get some
water between the tray and the plate surface to increase the thermal contact (increasing
freezing ability).
HARVESTING ICE
Plan to wait some time after the trays are frozen for them to thaw in a sink or away from
the plate in the refrigerator. When the outside surface is wet, invert the tray and let the
ice slide out.
STORAGE OF ICE CUBES
After ice has been made and harvested, store it in resealable plastic bags in the
refrigerator or if so equipped in the freezer. Ice trays left in contact with the plate will
melt rapidly if the plate goes above freezing.
DEFROSTING
It is important to defrost the holdover plate regularly; this will maximize the efficiency of
the system and ice making performance. It is not necessary to turn off the system to
defrost. Scrape off any frost with a piece of wood or galley utensil. A noticeable drop in
the cabinet temperature will occur.
BAG STYLE ICE MAKING
If your SEA FROST system is not equipped with the vertical tray kit, you can still make
ice. One method is to use zip-lock bags. When filled with water a clip binder or a clamp
of your own invention can hold the bag in contact with the plate.
5
BG 2000 MAINTENANCE
Like your engine, your SEA FROST needs periodic checking.
ROUTINELY CHECK:
1. The refrigerant charge. See: "Checking The Charge" text. NEVER OPERATE
SYSTEM WITHOUT PROPER CHARGE.
2. All components, all tubing, fittings, and hose clamps for corrosion and wear. BE
SURE TO LOCATE AND INSPECT ALL FITTINGS AND COMPONENTS IN THE
SYSTEM. KNOW THE LOCATION OF ALL CONNECTION POINTS. Spray with a rust
inhibitor REGULARLY. Corrosion unchecked in the marine environment will severely
reduce the life of your system.
CLEANING
The holdover plate surface protects itself with a layer of oxidation. You might find
that after a long period of storage the plate will look chalky. This will not effect operation
and is easily cleaned up with a pot scrubber and soap.
WATER STRAINER
The water pump must be protected from damage and blockage by a seawater
strainer. This strainer must be inspected and cleaned routinely.
ROUTINE SERVICE AND INSPECTION
We recommend sea strainer inspection before leaving the boat unattended dockside
with the unit on. A visual inspection may be adequate depending on the type of
strainer. To clean most types of strainers, close the seacock, open the strainer, remove
the screen or basket, clean, reassemble and open the seacock. Operate the system
and check for water flow and leaks around the strainer opening.
PUMP IMPELLER INSPECTION (if pump is inoperative)
The LC-3P pump is a sealed liquid cooled magnetic drive centrifugal pump. The
impeller may be inspected for obstructions and wear by first closing the seacock. Drain
the pump housing by removing a hose.
6
It is IMPORTANT that NO WATER flows between the plastic housing and the pump
body. The screws that hold the cover also seal the housing. Water behind the housing
will ruin the motor bearings.
BE SURE THE PUMP HOUSING IS ABSOLUTELY DRY BEFORE DISASSEMBLY.
Remove the phillips screws holding the inlet fitting plate (larger hose size). The impeller
may then be removed along with it’s ceramic seal and thrust washer. Reassemble in
the reverse order. (An exploded diagram is in this manual.) Observe the "O" ring that
seals the housing cover plate. Make sure it is in good condition. Open the seacock.
Inspect for leaks.
NEVER OPERATE THE PUMP WHILE DRY. IF IT IS SUSPECTED THAT THIS
CONDITION HAS OCCURRED, INSPECT THE IMPELLER AND HOUSING FOR
WEAR.
CHECKING THE REFRIGERANT CHARGE
SIGHT GLASS LOCATION
The BG 2000 system is fitted with a sight glass located in the top of the
RECEIVER/FILTER/DRIER (RFD). (The RFD is a round blue canister about 9 inches
high and 3 inches in diameter. It is located in the left corner of the compressor
housing.)
The charge level should be inspected to be sure refrigerant is of the proper amount and
that there are no slow leaks. Switch the unit on and immediately inspect the sight glass.
White foam with high velocity should be observed and after a minute or two show a
black or clear condition. A clear glass and an empty glass will look the same. A
transition must be seen to be sure that refrigerant is present. Do not operate a low or
empty system. See; "Leak Checking” and “Adding Charge". (Page 22)
LAY-UP (Winterizing)
Flush the pump and condenser with plenty of fresh water. Pressure water should be
flushed through the inlet side of the water pump. In freezing climates antifreeze should
be pumped through, after flushing, by operating the system for a very brief period.
Connect a short hose to the suction side of the pump to draw from a bucket. Run the
pump (switch on unit) until antifreeze is discharged. (The pump is not self-priming and
may require filling the hose and pump with a funnel). DO NOT RUN THE PUMP DRY.
It is water lubricated.
7
HOW REFRIGERATION WORKS
There are two important concepts to understand in order to learn about refrigeration.
They are latent heat and phase changes.
A great deal of heat is required to change a solid to a liquid, and a liquid to a gas. A
great deal of heat must be removed to reverse these changes. These changes are
called phase changes, or changes of state. The heat removed or added at these phase
changes has no effect on the temperature of the substances until the change is
complete. For instance, ice melts at 32 degrees F, water freezes at 32 degrees F also.
Ice and water will remain at 32 degrees F until the freezing or melting process is
complete. Latent heat is this hidden energy required to make or break the bonds in a
phase change.
By evaporating liquid to a vapor, we can absorb heat. By condensing a vapor to a
liquid, we give up heat. Refrigeration is the use of these phase changes to move heat
out of the icebox (cooling it).
We all know that cold is the absence of heat. A practical example of heat absorption by
evaporation is that of rubbing alcohol evaporating in your hand and cooling it. The
alcohol is actually using the heat from your hand to boil. The absorption of heat cools
your hand.
Pressure affects the temperature at which a gas phase change will occur. Using water
as an example, water boils at sea level at 212 degrees F. On top of Mt. Everest it boils
at a much lower temperature. The air pressure is lower allowing the water-to-steam
phase change to occur more easily. A pressure cooker increases the pressure on water
to restrict boiling to a higher temperature. A pressure cooker will cook food faster
because the temperature is higher. Remember that a phase change involves latent
heat. The temperature of boiling water is only 212 degrees F. at sea level. The
evaporation action is absorbing heat at a rate equal to the rate of heat applied,
preventing further temperature rise.
Let's look at Refrigerant-404-a (R-404-a). R-404-a will boil at minus 57 degrees F. at
sea level. By evaporating liquid R-404a in the SEA FROST plates heat is absorbed
making refrigerant vapor. To dispose of this heat, a condensing phase change is
necessary. By increasing the pressure (compressing) we can raise the boiling point of
the gas vapor. Heat is removed from the pressurized gas vapor at the condenser.
Seawater passing the condenser coils removes the heat, forcing the vapor to a liquid
state again. Pressure, therefore, is the key that allows passing the heat we have taken
from the icebox to a warmer place (the seawater) and converting the gas to a liquid to
be re-evaporated again.
8
By causing R-404a to boil (evaporate) in the SEAFROST plates, we absorb the heat
energy there. This activity cools the liquid solution within the plates, causing them to
change phase (freezing to a solid). By freezing this solution, we have increased its heat
absorption capacity more than 100 times.
When the cycle is stopped (compressor is turned off) the plates will begin to absorb the
heat that leaks through the insulation in the icebox. The absorption will be at a constant
temperature until the phase change to liquid (melting) is complete. This is the principle
of holdover refrigeration and the function of your SEA FROST.
9
INSTALLATION
Installer's care should be stressed. No matter how good SEA FROST equipment is, its
performance and life are in the hands of the installer. To insure your work:
1.
2.
3.
4.
5.
Read this manual.
Reread any aspect you don't understand.
Follow Swagelok fitting instructions carefully.
Spend enough time leak-checking to be sure there are no leaks.
Thanks from all of us who have to guarantee your work.
There are two contaminants that will give you problems in any refrigeration system.
They are WATER and DIRT. Moisture is always present and cannot be eliminated,
water in this case refers to puddles and drops. Dirt is any solid. The installer's habits
will be most important in ensuring a trouble-free start-up. We have added a large
receiver filter dryer (RFD) to take care of all dirt and moisture that might get into the
system during a careful installation. Moisture in the system is boiled off when the
system is evacuated, or it is captured in the desiccant. There is a screen in the
expansion valve to prevent dirt from plugging it.
Excess moisture that the RFD can't handle will plug the expansion valve with ice. This
ice stops the cycle. The only cure is to discharge the refrigerant, replace the RFD, reevacuate the system, and recharge it. This remedy takes time and is somewhat costly.
Keep the system clean when installing it to save time for something more fun.
TUBE HANDLING
Installation is quite simple. All the copper tube comes to you with the ends capped.
Any routing of the tube must be done with the tube either taped or capped. Cap both
tube ends after each cut. (Spare caps have been included). Work with only one line at
a time, and only uncap one end at a time.
TUBE CUTTING
Use only a tube cutter; hacksawing or any other method will introduce chips to the
system and also distort the tube, making connections difficult and leak-prone. A
miniature cutter is essential for this work. CUT SLOWLY to avoid a ridge on the inside
of the tube. We do not recommend reaming or dressing the cut, as it is very easy to get
chips of copper in the system, which may cause trouble.
TUBE BENDING
Make all but the long sweep bends with a spring bender; one kink and the line must be
rerun. Don't add any more fittings than are absolutely necessary. Route all lines in
such a way that they are most direct but out of the way. Again, keep everything sealed
until you are ready to make that connection.
10
NOTES ON SWAGELOK FITTINGS
Swagelok fittings come to you completely assembled, finger-tight. (Pieces a, b, and c in
Drawing #1 are already together). They are ready for immediate use.
Disassembly before use can result in dirt and foreign material getting into the fitting and
causing leaks. If disassembly is necessary, reassemble per Drawing # 1.
This is a double ferrule system. The most serious installation problem encountered with
SEA FROST is the incorrect assembly of these fittings. Be absolutely sure that you
assemble all fittings as in Drawing #1.
To ease assembly slacken the fitting nut slightly before pushing onto the tube, then
retighten with fingers before tightening with a wrench. (This is to avoid cross threading.)
Step 1. Always leave two inches of straight, undistorted tubing leading to all Swagelok
fittings to allow a proper connection.
Step 2. Prior to inserting 1/2" tubing into Swagelok tube fitting, make a pencil mark one
inch from the end of the tube. Prior to inserting 3/8" tubing, make a pencil mark 3/4"
from the end of the tube. With 1/4" tubing make the mark 5/8" from the end.
Step 3. Insert clean, smooth tubing with the pencil mark into the Swagelok tube fitting.
You can be sure the tube is resting firmly on the shoulder of the fitting when the pencil
mark is flush with the nut.
Step 4. Tighten the Swagelok nut to a wrench snug* position. Scribe the nut with a
pencil at the 6:00 o'clock position. (See drawing #1 step # 2.)
* Wrench snug is the first point in the assembly tightening when the tube can not be
pulled from the fitting, (i.e. when the ferrules tighten enough to contact the tubing).
Step 5. Now, while holding the fitting body with a back-up wrench, tighten the nut oneand-one-quarter turns (1-1/4). To do so, watch the scribe mark, make one complete
revolution, and continue to the 9:00 o'clock position. (See drawing # 1, step #3.)
11
DRAWING 1
STEP 1
Simply insert the tubing into the SWAGELOK
tube fitting. Make sure that the tubing rest
firmly on the shoulder of the fitting and
that the nut is wrench snug.
STEP 2
Before tightening the SWAGELOK nut,
scribe the nut at the six o'clock position.
12
STEP 3
Now, while holding the fitting body steady
with a backup wrench, tighten the nut 1 1/4
turns. Watch the scribe mark, make one
complete revolution and continue to the 9
o'clock position. By scribing the nut at the 6
o'clock position as it appears to you, there
will be no doubt as to the starting position.
When tightened 1 1/4 turns to the 9 o'clock
position you can easily see that the fitting
has been properly installed.
* SWAGELOK FITTINGS ARE TO BE TIGHTENED TO A TORQUE SPEC, NOT
INFINITE TIGHTNESS. BE SURE YOUR STARTING POINT IS WRENCH SNUG.
(SEE STEP 4 on page 12.) A DISTORTED TUBE MIGHT GIVE A FALSE STARTING
POINT.
* Swagelok fittings have a built-in spring interaction between the ferrules. This
compensates for temperature changes and allows the fittings to be reconnected many
times. As the fitting is tightened, a burnishing occurs between the body of the fitting and
the ferrules and between the ferrules and the tube. This action provides the tightest
connection available.
* When making all connections, USE TWO WRENCHES. Don't allow the fittings to turn
or twist when tightening.
RECONNECTING PRE-SWAGED FITTINGS
Connections can be disconnected and retightened many times.
When reconnecting, insert the tubing with pre-swaged ferrules into the fitting until the
front ferrule seats in the fitting. Tighten the nut by hand to prevent cross threading.
Tighten the nut one-quarter of a turn with a wrench (or to original one-and-one-quarter
tight position). Then snug slightly with the wrench. No more than an additional 1/8 turn.
13
CONDENSING UNIT LOCATION AND MOUNTING
The design of the BG 2000 allows placement of the unit in an enclosed space such as a
cabin locker, sail locker or engine area.
The BG 2000 is a high-powered unit. It produces some noise and vibration. Its duty
cycle will be short however, consider that dockside operation may be noticed when the
generator is not masking the sound. Bulkhead mounting is fine, but avoid mounting on
a bulkhead that may resonate into the cabin area. If an under bunk installation is used,
turning off the thermostat at night will avoid startling you should the unit start.
SERVICE ACCESS
Service access and installation require that the front and left end (water fitting end) be
accessible.
RECEIVER FILTER DRIER (RFD) VISIBILITY
LOCATION: The RFD is in the left corner of the compressor unit. Be sure that it can be
viewed from the top. A mirror might be mounted above the glass to allow ease of
inspection if the unit is to be mounted close to an overhang or under a deck.
MOUNTING
Mount the BG 2000 level. The unit may be bulkhead or platform mounted. It may be
hung from its case. Use the aluminum ell brackets supplied. The 1/4-20 X 1-3/4
Stainless screws thread into the Well-nut mounts at the back corners of the housing.
Mount holes for standard fasteners are also drilled in the forward edge of the bottom of
the cabinet.
PLATE MOUNTING
SEA FROST holdover plates mount with a
"Wellnut" expandable neoprene blind hole
fastener. A template or the part itself
should be used to locate the mounting
holes. Drill 1/4" pilot holes then increase
them to 1/2". Install the screw into the
mounting tab then screw the mount onto
the screw. Install the plate pushing the
rubber mounts Into the predrilled holes.
Tighten the screws firmly.
14
INSTALLING THE THERMOSTATIC EXPANSION VALVE
The larger fitting on the thermostatic expansion valve connects with a Swagelok to one
of the plate tubes. In a multiple plate series system ½” copper jumper lines will connect
the plates to each other. The last plate has a ½” return line to the compressor. The
feeler bulb from the valve must be strapped to this return line inside the refrigerated
space. Plan the tube run to allow for the length of the capillary (about 50 “). On a vertical
run the capillary tube connection should be up above the bulb. It is critical that the feeler
bulb be in excellent contact with the copper tube. Be sure to locate the feeler on a strait
section of tube. Strap the bulb to the line with the two copper straps, bolts, and nuts.
Coil and secure the excess capillary tube between the valve and bulb with nylon cable
ties. Do not let the capillary tube contact other tubes or the plate surfaces.
The valve is supplied by a ¼” copper tube from the compressor. This is a Swagelok
connection.
15
RUNNING THE TUBING
Make the connection to the compressor and RFD after all other connections are
made.
A 1/4" copper tube runs between the compressor unit and the expansion valve. Multiple
plate hook-ups should be assembled as indicated by the specific diagram provided.
A 1/2" line connects the plate outlet to the compressor. If possible run the 1/4" liquid line
in contact with the 1/2” line. This will be insulated in proper sequence. Support the
tubing every 12 to 18 inches as necessary with tie wraps after leak checking and
insulating.
PUMP INSTALLATION
Proper pump installation is important for pump operation. The BG 2000 uses a
centrifugal pump, which is not self-priming. Air pockets caused by loops or descending
lines from one component to the other may cause pump problems. This pump is water
cooled and lubricated, it must never be run dry, doing so will cause the wet end to be
destroyed if it is started or run dry. A separate through hull fitting 3/4" or larger should
be used. The intake should be as low in the boat as possible and away from head and
cockpit drains. A forward facing scoop will prevent problems if the unit is operating
underway.
A large seawater strainer should be mounted above the seacock.
The pump should be mounted horizontally and it should be higher than the strainer.
The discharge should be on the top. Refer to the pump drawing at the back of this
manual.
WARNING: READ SAFETY SECTION BEFORE PROCEEDING
FINAL ASSEMBLY
The RFD contains desiccant to absorb moisture and the compressor oil is hydroscopic
therefore it is important to open the compressor and RFD fittings after all other
connections are made and the system is ready to be commissioned.
The BG 2000 unit is shipped with some nitrogen pressure. Before removing the caps
on the connection ports remove the screw caps on the access valves and depress the
cores with a clean retracted pen point to vent any existing pressure.
After depressurizing, working with one connection at a time, remove the Swagelok caps
from compressor and liquid line. Attach in the proper assembly sequence the front and
back ferrules and the Swagelok nuts. (Refer to the Swagelok instructions on page 12.)
16
RFD (Receiver Filter Drier)
The RFD contains desiccant to absorb moisture This
absorption is limited. Leaving the RFD installed on a
partially open system may reduce its capacity by
allowing it to absorb moisture.
The RFD is a reservoir for excess refrigerant. The
RFD also contains a sight glass in the top. A pick-up
tube extends from the bottom of the canister to the
outlet.
THERMOSTAT
For the best looking job the thermostat should be cut into a panel. (We do not
recommend installation in the insulation or in the box, as the control is not moisture
protected.) A cutting template is provided. Locate the thermostat close enough for the
"bulb" tube to reach. It is only necessary that the bulb end of the sensing tube be
installed on the plate. Use one of the mount screws for attaching the thermostat bulb
clip to the plates. Secure any excess in a coil in the refrigerated space. Do not allow
the sensing tube to contact any of the copper tubes. The sensing tube is hollow and
filled with refrigerant; avoid bending it, which could cause it to crack and leak. Excess
capillary tube should be left in the refrigerated box.
THERMOSTAT WIRING
The thermostat electrical leads are low voltage for safety. Connect the red thermostat
wires to the two terminal screws in the BG 2000 terminal box. Use the # 8 ring
terminals provided.
AC LINE CIRCUIT
A separate 30-AMPbreaker is required for the 110 volt AC circuit. A 15 amp double
breaker should be used on a 230-volt unit. We recommend following ABYC guidelines
for wire specifications and wiring procedures.
CONNECTION ACCESS
Remove the two screws in the front panel to revel the line terminal board, pump supply,
and thermostat connections.
17
WIRING THE PUMP
The pump is connected by three wires at the compressor unit. The pump operation is
controlled by the BG2000.
REFRIGERANT HANDLING AND SAFETY
Do not proceed with any aspect of a procedure if you do not fully understand the
procedure and know what result to expect. Understand that pressure exists in
refrigeration systems. Be careful.
REFRIGERANT
SEAFROST is charged with REFRIGERANT-404a. REFRIGERANT-404a is a blend of
HFC refrigerants. It is odorless. Its boiling point is -57. Degrees F. at sea level. It is
heavier than air. It's label and container color is orange.
GENERAL SAFETY THIS IS IMPORTANT. READ THIS!
R-404a is safe if handled properly. Avoid breathing vapors and prolonged skin
exposure. Avoid using in areas of open flames. The vapor is heavier than air and may
reduce oxygen available for breathing. Use with sufficient ventilation to keep exposure
below recommended limits. Do not mix with air for leak testing or use with air for
any purpose above atmospheric pressure. Liquid R-404a will freeze skin. It's
especially dangerous to the irreparable tissues of the eyes.
--WEAR EYE PROTECTION--
Do not pressurize an empty system with R-404a without first evacuating the
system with a vacuum pump.
WARNING: DANGER NEVER OPERATE A SYSTEM WITH THE HIGH SIDE
(DISCHARGE) OPEN TO THE REFRIGERANT SUPPLY. PRESSURIZATION OF THE
REFRIGERANT SUPPLY COULD CAUSE IT TO BURST.
18
PROCEDURES FOR WORKING WITH R-404a
1) A new uncharged system must be evacuated before adding R-404a.
2) An R-404a system must only be pressurized with R-404a or nitrogen.
3) Only service tools dedicated to R-404a are to be used. No parts, tubing, fittings,
receivers, dryers, service gauges, or any refrigerant carrying components may be fitted
to a R-404a system from a used system or from a CFC based system. Damage caused
by the use of parts not supplied by Sea Frost for a R-404a system will cancel all claims
against Sea Frost.
4) No oil is to be added to the BG 2000 system but polyolester oil supplied by Sea
Frost, labeled and capped for BG 2000 use. No oil is to be added to a system without
prior consultation with Sea Frost.
5) The oils used in R-404a systems are moisture sensitive (hydroscopic). Do not leave
any tube end or component connection open to air while assembling the system. Be
sure to use only new capped copper tubing and be sure to cap the copper coil after
cutting it.
ACCESS TO THE SYSTEM: SERVICE PORTS
The service ports are two small capped valves. The low-pressure valve is mounted on
the BG 2000 compressor. The high-pressure valve is mounted on a copper tube in the
cabinet behind the RFD. (See drawing pg. 33) The ports are standard ¼ inch male
flares with core valves. Hose connections must have the proper core depressor insert
in it to access the system.
Be sure the caps are installed tightly after charging or service.
NOTE: THIS SYSTEM IS DESIGNED FOR R-404a. IT MUST BE CHARGED WITH R404a ONLY. ONLY DEDICATED R-404a GAUGES AND EQUIPMENT ARE TO BE
USED. ANY CONTAMINATION FROM CFC BASED REFRIGERANTS WILL
DESTROY THIS SYSTEM.
19
GAUGES
Gauges must be used in the evacuation and charging. They will provide information on
the operation of the system when troubleshooting.
A gauge sets consist of two gauges installed in a manifold with two valves and hoses to
connect the gauges to the system. The left gauge (blue) is a compound device; it
indicates pressure and also vacuum. The right gauge (red) indicates pressure only.
The valves open a center port (yellow) to the left or right side respectively. Operation of
the valves is only necessary when moving refrigerant or evacuating. With the valves
closed, the gauges read the pressures of the connection points.
VENTING THE GAUGE SET
TO ATTACH TO A CHARGED SYSTEM
Before operating the compressor on a charged system vent the hoses for a few
seconds by slacking the hose connections at the manifold body after connecting. This
will prevent air trapped in the gauge hoses from entering the system.
DISCONNECTING GAUGES
Disconnecting the gauge set after running the system may be done by turning off
the compressor and allowing the pressures to equalize on the gauges then rapidly
unscrewing the hoses from the service ports.
20
Disconnecting the gauge set on a static system may be done by rapidly unscrewing
the hoses from the service ports.
Adding charge to a working system should be done through the suction side (blue)
as liquid. The suction pressure must be monitored and not allowed to rise more then 15
PSIG above operating pressure.
VENTING THE CHARGE HOSE
WHEN ATTACHING GAUGES TO A CHARGED SYSTEM
Note: This procedure will vary with the type of gauges being used. Be sure to vent the
charge hose to the gauge set before opening the valve to add refrigerant.
LIQUID CHARGING
REFRIGERANT IS EITHER a vapor or liquid. R-404a is a blend that may separate if
vapor charged. To supply LIQUID to a system, keep the refrigerant canister in the
inverted position (valve down). If properly handled the refrigerant will flash to vapor
when charging.
COMMISSIONING PROCEDURE
EVACUATION WITH A VACUUM PUMP
Evacuation removes air, readying the system for charging.
Connect a gauge set to the service ports. (See "Access Port Location” page 33)
Connect the gauge center hose to a high vacuum pump. Start the pump and slowly
open the low side/suction gauge hand wheel. As the vacuum drops below 20 inches
open both hand wheels fully.
EVACUATION LEAK TEST
Evacuate the system to the best vacuum (lowest pressure). As the gauge reaches this
low pressure close the valves on the manifold. Observe the vacuum gauge and be sure
the pressure remains constant for 5 minutes. If the pressure rises rapidly check all the
connections again. Re evacuate to the lowest pressure and test by holding a vacuum
with the gauges closed. Be sure the system will hold this vacuum. Proceed by opening
the valves and continuing the evacuation process for 30 minutes or more. A micron
gauge can be used to measure the vacuum. Proper dehydration and evacuation should
be in the range of 200 to 500 microns.
21
NEW SYSTEM CHARGING
INTRODUCING INITIAL CHARGE
After the evacuation leak test and pump down, shut off the manifold valves, disconnect
the center hose from the pump and connect it to a cylinder of refrigerant Vent the hose
from cylinder (refrigerant supply) to the manifold. With the refrigerant can in the
inverted (liquid) position, open the discharge side valve (high side) valve and weigh in
about 6 oz of refrigerant. This should provide a saturated vapor producing a pressure
matching the pressure temperature chart. Close the valve and begin an inspection of all
the connections in the system. Begin leak checking the entire system.
LEAK CHECKING
Leak checking is a very important step, which should be done with diligence. A leak will
cripple this system. Please take the time needed to be sure all connections are tight.
Check every connection even the ones that were pre-made in manufacture.
The evacuation leak test is a preliminary check and is not to be considered a system
leak check.
LEAK CHECKING A CHARGED SYSTEM
ABOUT PRESSURES
Refrigerant in a saturated condition, i.e. part liquid and part vapor, will exert a pressure
that is a function of its temperature. The higher the temperature, the higher the
pressure. Avoid leak checking in cold weather or on a cold system.
A refrigerant leak will show with moderate pressure. (A leak is not a function of
pressure. Pressure is only required to aid in detection).
There are two ways to leak-check a pressurized system:
1. Soap bubbles (a solution of dish soap and water works well).
2. An HFC electronic leak detector probe, which senses the presence of refrigerant
molecules.
22
TO CHECK WITH BUBBLES
Soap each connection and observe all sides of the connection with a bright light and a
mirror. A leak will blow bubbles. Without careful examination and plenty of pressure
this test is not reliable.
TO CHECK WITH AN ELECTRONIC DETECTOR
Use a detector designed for HFCs. Slowly trace the area with the probe. Refrigerant is
heavier than air, therefore, trace below the fitting. Most units can be calibrated to home
in, on a leak. (See detector instructions). We use and recommend electronic detection.
TIF brand detectors can accurately detect leaks as low as 1/2-oz loss per year. This
sensitivity exceeds S.A.E. leak specifications. Be sure to test the operation of the
detector before and after you leak check the system
IF A LEAK IS DETECTED
Try tightening the Swagelok nut slightly. (See "Swagelok fittings"). If the leak is not
stopped, it is possible that the fitting was incorrectly assembled. Discharge (reclaim) the
refrigerant, and then disassemble the fitting for inspection. After reassembly, proceed
with evacuation leak test.
SPECIAL NOTE
- Be aware that propellants and solvents in sprays and foams may upset electronic
detectors.
- To confirm a leak detected with a detector use bubbles and be sure it is a leak and not
some erroneous vapor that is upsetting the machine.
- Electronic detectors do not function below 40.F.
- A good leak detector is able to pick up leaks as low as 1/2 oz per year.
FINAL CHARGING
This procedure must follow "Evacuation Leak Test" and "Introducing Initial Charge".
1. With the refrigerant supply still attached to the suction service port from the
previous procedure, open the cylinder valve (and the appropriate gauge wheel).
2. While closely observing the sight glass in the RFD, start the compressor by
switching on the circuit breaker and then turning on the thermostat.
23
3. The sight glass will show a stream of foam indicating a partial charge.
4. Introduce liquid refrigerant (liquid is supplied by keeping the cylinder inverted) at
a controlled pressure regulated by slightly opening the blue hand wheel valve.
Keep the low side pressure no more than 15 PSIG above the indicated operating
pressure. Add refrigerant for 30 seconds then turn off the supply and observe
the sight glass and cooling operation for 2 minutes before adding refrigerant the
same way again. Repeat this filling and observing. At the time the return line
frosts the sight glass should be clearing. Let the system operate for 30 minutes
with a mostly clear glass before adding a small shot for good measure (4 oz).
Do not exceed the 24 oz maximum charge amount regardless of the sight glass
reading. Compare pressures with the pressure trends page 32. When a
sufficient amount of refrigerant has been added to the system (A new system
holds 24 oz. maximum) the sight glass will clear, indicating sufficient charge.
When charging a hot system, (cabinet and plates over 80 degrees F) the sight
glass will usually clear as the return line at the valve becomes frosted.
5. When observation and test operation have been completed, disconnect the
gauges. Replace the service port caps.
6. Re-check all connection points for leaks.
7. Spray the acrylic coating, or similar rust inhibitor, on all the components and
fittings while they are clean and dry.
READING THE SIGHT GLASS
A clear sight glass when the compressor is operating signifies a sufficiently charged
SEA FROST BG 2000 System. To determine the meaning of "clear", notice the
appearance of the RFD sight glass when the system is at rest with the compressor off.
This is a "clear" glass.
SPECIAL WARNING: A clear sight glass can also indicate a completely EMPTY
system. Any time the compressor is started, a white stream of foam should
appear in the sight glass indicating that refrigerant is present. This foam may
disappear quite quickly, but IF NO FOAM IS EVIDENT, the system is empty. DO
NOT OPERATE THE SYSTEM if empty. Operation in this mode will ruin the
compressor. Turn off the main breaker to prevent operation until system can be
properly leak tested and recharged.
24
A white stream of fast moving foam with the compressor operating indicates an
insufficient charge level. Watch closely for a transition from foam to total liquid,
indicated by a clear sight glass. This transition point can be missed if proper attention is
not given. Also, IT IS POSSIBLE for the sight glass to show large bubbles even when
the charge is sufficient, so it is important to differentiate between foam and bubbles.
The foam condition has velocity and direction; the bubbles are large, temporary, and
nearly stationary. Do not try to chase away these larger bubbles with more refrigerant;
overcharging must be avoided. Air in the system may give a false sight glass reading,
which could lead to overcharging. If in doubt, discharge a suspected overcharged
system and charge again. MONITOR THE SIGHT GLASS CONTINUALLY. The glass
will not indicate when the system is overcharged.
In a warm system, when the plates are above freezing (32.F) upon start-up, the sight
glass may take several minutes to clear. A cold system, in cold water, may show a
clear glass within seconds of start-up.
RFD SIGHT GLASS DETAIL
CLEAR (OR EMPTY)
STATIONARY BUBBLES
FOAM/LOW
PROPER CHARGE AMOUNT
THE BG 2000 SYSTEM IS DESIGNED TO HOLD 24 OUNCES. THIS IS THE
MAXIMUM CHARGE. The sight glass must clear by the time the return line
(suction/large diameter tube) goes below 32 degrees F.
GENERAL INFORMATION
OPERATING PRESSURES will vary with water temperature, and water flow.
Generally, the HIGH SIDE will peak with warm plates in two to four minutes. Increasing
pressure indicates an overcharge or no water flow. The LOW SIDE will drop rapidly to
the 20 to 10 range, and then slowly drop. The low side tubing will freeze. The low side
pressure will drop more rapidly when the seawater is cold. A deep vacuum indicates
the system is frozen with moisture or the valve is plugged with dirt or contaminants.
Failure to "pull down" indicates the valve is malfunctioning or flooding.
The compressor will feel warm in normal operation.
Every valve has been operated prior to shipment. There are no field superheat
adjustments.
25
SPECIAL NOTE
R-404a will become cloudy and indicate similar foaming in the sight glass as the
pressure on the hi-pressure side of the systems becomes too great. Adding charge to
clear this condition will damage the compressor. Be sure you know the pressures you
should have for the corresponding water temperature.
CHECKING THE REFRIGERANT CHARGE
PERIODIC INSPECTION
Checking the refrigerant charge must be incorporated into a routine maintenance
schedule.
1) Locate the RFD (receiver filter drier). It is a blue metal can about 10 inches high and
three inches in diameter, with brass fittings connecting it to copper tubing. The RFD
has a sight glass for viewing the flow of the refrigerant. It is located in the left corner of
the compressor housing.
2) Start the BG 2000. Check to be sure that it is pumping water.
3) MONITOR THE SIGHT GLASS CONTINUALLY. If the sight glass does not show a
presence of refrigerant within a minute of operation the system is empty. TURN OFF
THE SYSTEM, and follow the procedure in the troubleshooting section.
4) If the white foam is evident watch closely for the transition to clear. If the glass
indicates insufficient charge level, additional charge will be needed
5) Feel the SEA FROST plates in the icebox 10 minutes after start up. If the sight glass
clears yet the plate’s temperature does not drop, turn the system off and follow the
procedure in troubleshooting section.
6) If the proper charge is indicated, make ice, go sailing.
DISCHARGING THE SYSTEM (RECLAIMING)
Before the connections or components can be disassembled, the system must be
discharged. Connect a gauge set to the suction service port. Slowly vent the
refrigerant (keeping the pressure under 20 psi) into an approved reclaiming system. Do
not loosen any connections until the gauge on the refrigeration system shows 10”
vacuum for 10 minutes.
26
TROUBLESHOOTING
The most common problems that can occur in a SEA FROST BG 2000 System are:
(1) Overcharge or loss of water flow switching off the manual reset high-pressure
switch.
(2) Loss of refrigerant charge resulting from leaks.
(3) Moisture or dirt plugging the expansion valve.
(4) Compressor damage due to loss of refrigerant charge.
STEP 1. Gather information as to the nature of the problem before operating the
system. A leak often leaves a trace of oil. Inspect the fittings and tubing for wear,
corrosion, and chafe. Do not operate the compressor until the trouble is corrected.
HIGH PRESSURE CUTOUT/MANUAL RESET BUTTON
The compressor is fitted with a MANUAL RESET high-pressure switch. The switch is
located on the left end of the BG 2000 unit. (See drawing). This switch will disconnect
the thermostat circuit switching off the compressor and water pump. Pushing the red
rubber button after the unit has rested for a few minutes will reset the switch. A
faint click will be heard when the button resets.
BEFORE RESETTING the switch inspect the pump and strainer. If the installation
location of the through hull allows air to enter the system it may be necessary to bleed
the air from a hose connection after the pump but below the waterline by loosening a
hose connection. When water flows from the connection retighten the connection.
*This switch will disconnect if the water flow stops.
*This switch will disconnect if the system is overcharged.
Overcharge may not appear until the boat moves into warmer water than it has been
commissioned in. Discharge the system until the unit operates without activating the
high-pressure switch. Be sure that the sight glass still runs clear.
For further troubleshooting, attach purged gauges at the compressor.
a) If the refrigerator box and SEA FROST plates are warm and pressure readings
are below 100psi with compressor off (in 50 degree F or higher ambient conditions),
pressurize system with R-404a and leak-check. After leaks have been located,
repaired, and tested, install a new RFD (Receiver/filter/drier) - see instructions below in
Step 3.
27
b) If pressure reading is over 100 psig with compressor off, proceed to check charge
level via sight glass and charge if needed.
CHARGE LOSS INDICATES A LEAK THAT MUST BE CORRECTED.
STEP 2. If a system continues to operate inefficiently after Step 1, check for moisture
or dirt plugging the valve. Run the system, observing closely the gauge readings and
plates temperature, noting the following.
a) If system is warm upon start-up, a DIRT-PLUGGED Valve will show an
immediate deep vacuum reading on low side. Consult Sea Frost for cleaning
techniques.
b) MOISTURE-PLUGGED VALVE on a properly charged system is indicated by
deep vacuum readings on low side after a few minutes of operation from warm,
FOLLOWED BY any combination of these symptoms:
-High side compressor discharge fitting temperature drops from hot to warm.
-Suction line from valve remains warm.
-Compressor current draw (Running amperes.) drops.
-Moisture enters either through a low side leak or during initial installation and will freeze
at the valve unit, reducing or eliminating refrigeration. Turning off system and allowing
the valve to warm to above freezing, then restarting, may temporarily solve the problem.
If not, change RFD as follows.
STEP 3. To change a saturated RFD, allow the system to warm to ambient
temperature, thereby preventing moisture from condensing in the circuit upon opening.
A light bulb in the refrigerator box will speed the warming of the plates. Recover the
refrigerant from system through the suction service port SLOWLY to prevent liquid and
oil from escaping. " WARNING: BEFORE DISASSEMBLY OF ANY PART IN THIS
SYSTEM, BE SURE CHARGE IS COMPLETELY RECOVERED. With a backup
wrench holding the brass body of the Swagelok fittings loosen and back off the nuts.
The tubing may be pulled out of the fittings. Remove the RFD. Replace only with an
identical unit by size and color: THE SEA FROST RFD is a drier and also a
receiver/filter. The desiccant and the oil in the Sea Frost RFD are special to this
system and R-404a. Using the wrong oil will destroy the system.
NOTE: This system contains a measured amount of lubricating oil. Be sure the RFD
being installed is a blue SEAFROST BG 2000 R-404-a RFD. Record all component
exchanges in this on-board owner's manual.
28
Follow the "re-make" instructions for Swagelok fittings.
Reminder: To ensure the total removal of moisture from the system use a high vacuum
pump, and evacuate the system with the highest possible plate temperature (100
degrees F.). A light bulb or heat lamp in contact with the plates is a good technique.
Recharge. Refer to "Recharging section"
MOISTURE IS A SYMPTOM. Carefully leak check the low side of the system if
moisture becomes a problem. Moisture leaks in!
CALL US WITH ANY QUESTIONS
INTERNATIONAL 603-868-5720
TOLL FREE IN THE UNITED STATES,
CANADA, AND CARIBBEAN
800-435-6708
FAX 603 868 1040
SHIPPING AND MAIL:
SEA FROST
372 ROUTE 4
BARRINGTON NH 03825
USA
29
BG 2000 Specifications and Operating Characteristics
Horsepower
Refrigerant
Oil
Locked rotor amps
Current draw with pump
Electrical breaker
115-volt 50/60 hz
1 HP
404-a
Polyol ester oil
76.7
26.8 amps
30 amp
Maximum refrigerant charge
Manual reset high pressure cut-out
March pump
Integral low voltage thermostat circuit
24 oz
325 PSIG
LC-3
24-volt AC
230-volt 50/60 hz
1HP
404-a
Polyol ester oil
45
14.10 amps
15 amp double
pole
24 oz
325 PSIG
LC-3
24-volt AC
Pressure trends: Gauge pressure PSIG
Hi Pressure
Low Pressure (Warm Plates)
Low pressure (Cold Plates)
Water temp 60
degrees F.
175
30
7 to 5
Water temp 80
degrees F.
190
30
7 to 5
Pressures are approximate: High pressure will momentarily rise beyond operating
pressure until the expansion valve starts to restrict flow. Condensing pressure will be
15 degrees above water temp.
Low pressure will drop from equalized at start up to settle at the indicated low reading in
a period of about 45 minutes depending on the number of plates and starting
temperature. Proper thermostat set up should cycle the compressor in this lowpressure range.
THE EXPANSION VALVES HAVE BEEN FACTORY ADJUSTED FOR OPTIMUM
PERFORMANCE. DO NOT ADJUST THIS VALVE FOR ANY REASON.
INCORRECT SETTINGS MAY RUIN THE COMPRESSOR!
30
Figure 1
31
WATER CIRCUIT
32
33
34
35
372 ROUTE 4 BARRINGTON, NH 03825 USA
TEL (603) 868-5720
FAX (603) 868-1040
E-Mail:[email protected]
1-800-435-6708
www.seafrost.com
THERMOSTAT CALIBRATION INSTRUCTIONS
Note: Be sure that the unit is operating properly before making any thermostat
adjustments. The sensing bulb must be in excellent thermal contact with the plate or
block.
The range of this control may be changed. To access the adjustment screw, remove
the four mounting screws on the thermostat panel. Tip the panel forward and remove
the protective tape to expose a slot in the case. Make the adjustment with a torx or
small phillips head screwdriver.
Make small adjustments. Record all adjustments.
If the lowest setting on the thermostat panel (1-snowflake) is too cold:
•
Turn the adjustment screw clockwise. One 360-degree turn will raise the box
temperature approximately 6 degrees f.
If the highest setting on the thermostat panel (3-snowflakes) is too warm:
•
Turn the adjustment screw counterclockwise.
36
HOLDOVER PLATES
STAINLESS STEEL
EVAPORATOR PLATES
37
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