For 13 SEER R410A Unitary Ducted Split AC &

For 13 SEER R410A Unitary
Ducted Split AC & Heat Pump
Installation Manual
Residential Air Conditioners & Heat Pumps
Thank you for choosing Residential Air Conditioners & Heat Pumps, please read this
Installation manual carefully before operation and retain it for future reference.
MRCOOL reserves the right to interpret this manual which will be subject to any change due
to product improvement without further notice.
Contents
Safety Considerations....................................................................................1
1. Unit Parts Arrangement..............................................................................2
2. Physical Dimension....................................................................................3
2.1 Outdoor Unit.....................................................................................3
2.2 Installation Clearance Data....................................................................5
2.3 Units Installation.....................................................................................5
2.4 Installation Recommendations ..............................................................6
3. Brazing Connections..................................................................................7
3.1 Preparation the Line ..............................................................................7
3.2 Cap and Core Removal..........................................................................8
3.3 Attach Gauge..........................................................................................8
3.4 Braze Line Set........................................................................................8
3.5 Preparation for Next Step.......................................................................9
4. Check Piston..............................................................................................9
5. Operating Gauge Set and Service Valves................................................10
5.1 Torque Requirements...........................................................................10
5.2 Using Manifold Gauge Set...................................................................10
5.3 Operating Service Valves ....................................................................10
5.4 Operating Angle Type Service Valve....................................................10
5.5 To Access Service Port......................................................................... 11
5.6 Reinstall Stem Cap............................................................................... 11
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5.7 Install Liquid Line Filter Drier Indoor .................................................... 11
6. Recovering Refrigerant from Existing System..........................................12
6.1 Disconnect Power................................................................................12
6.2 Connect Manifold Gauge Set...............................................................12
6.3 Recovering Refrigerant...................................................................12
6.4 Leak Test Line Set and Indoor Coil......................................................13
6.5 Evacuating Line Set and Indoor Coil....................................................14
7. Electrical...................................................................................................15
7.1 Size Circuit And Install Disconnect Switch...........................................16
7.2 Install Thermostat.................................................................................16
7.3 Unit Low Voltage Connections.............................................................16
7.4 Unit High Voltage Connections.............................................................17
8. System Refrigerant...................................................................................21
8.1 Gauge Set (Cooling Only)..............................................................21
8.2 Gauge Set (Heat Pump) ......................................................................22
8.3 Weigh In...............................................................................................23
9. Unit Control............................................................................................27
9.1 Mainboard Description.......................................................................27
9.2 Terminal Description...........................................................................28
9.3 Control Flowchart...............................................................................29
9.4 Error Analysis.....................................................................................30
9.5 Setting on Defrost Control PCB (for Heat Pump unit only) ................33
9.6 Manually Defrost Cycle .....................................................................33
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Unitary Ducted Split AC & HP
Safety Considerations
Improper installation, adjustment, alteration, service, maintenance, or use can cause explosion,
fire, electrical shock, or other conditions which may cause death, personal injury, or property
damage. Instructions for installation and use of this product are provided by the manufacturer.
Installation must be performed in accordance with the requirements of NEC and CEC by qualified
installer or agency only. The qualified installer or agency must use factory--authorized kits or
accessories when modifying this product. Refer to the individual instructions packaged with the kits
or accessories when installing. Follow all safety codes. Wear safety glasses, protective clothing,
and work gloves. Use quenching cloth for brazing operations. Have fire extinguisher available.
Read these instructions thoroughly and follow all warnings or cautions included in literature and
attached to the unit. Consult local building codes and National Electrical Code (NEC) for special
requirements. Recognize safety information. This is the safety--alert symbol .When you see this
symbol on the unit and in instructions or manuals, be alert to the potential for personal injury.
Understand these signal words; DANGER, WARNING, and CAUTION. These words are used with
the safety--alert symbol. DANGER identifies the most serious hazards which will result in severe
personal injury or death. WARNING signifies hazards which could result in personal injury or
death. CAUTION is used to identify unsafe practices which may result in minor personal injury or
product and property damage. NOTE is used to highlight suggestions which will result in enhanced
installation, reliability, or operation.
WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury or death.
Before installing, modifying, or servicing system,main electrical disconnect switch must be in
the OFF position. There may be more than 1 disconnect switch. Lock out and tag switch with a
suitable warning label.
This product must not be disposed together with the domestic waste.
This product has to be disposed at an authorized place for recycling of
electrical and electronic appliances.
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Unitary Ducted Split AC & HP
1. Unit Parts Arrangement
Cooling Only Condensing Unit
Compressor harness
Low pressure switch
High pressure switch
Compressor
Filter
Vapor line service valve
Liquid line service valve
Fig.1
Heat Pump Condensing Unit
High pressure switch
Low pressure switch
Compressor harness
Compressor
Filter
Throttle
Revesing valve
Vapor line service valve
Nozzle for adding freon
Liquid line service valve
Fig.2
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2. Physical Dimension
2.1 Outdoor Unit
Fan motor
H
Axial flow fan
Compressor
D
W
Fig.3—Outdoor Unit
Table 1—Dimension of Outdoor Unit
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Unit: Inch (mm)
MODEL
DIMENSION
H
D
W
MAC13018
24"(610)
21-1/2"(546)
21-1/2"(546)
MAC13024
24-1/2"(620)
24"(610)
24"(610)
MAC13030
29"(735)
24"(610)
24"(610)
MAC13036
29"(735)
28"(710)
28"(710)
MAC13042
29"(735)
28"(710)
28"(710)
MAC13048
29"(735)
28"(710)
28"(710)
MAC13060
33-1/2"(850)
29-1/2"(750)
29-1/2"(750)
MHP13018
24-1/2"(620)
24"(610)
24"(610)
MHP13024
24-1/2"(620)
24"(610)
24"(610)
MHP13030
29"(735)
28"(710)
28"(710)
MHP13036
29"(735)
28"(710)
28"(710)
MHP13042
29"(735)
28"(710)
28"(710)
MHP13048
33-1/2"(850)
28"(710)
28"(710)
MHP13060
33-1/2"(850)
29-1/2"(750)
29-1/2"(750)
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2.2 Installation Clearance Data
>3000mm
(120inch)
Floor
>1000mm
(40inch)
>1000mm
(40inch)
>1000mm
(40inch)
>800mm
(32inch)
>1000mm
(40inch)
Floor
Fig.4
2.3 Units Installation
2.3.1 Installation Positions of Condensing Units
● Outdoor Unit must be fixed on stable and solid surface of floor.
● Don’t install Outdoor Unit under window or between buildings, and prevent the operation
noise from room.
● There should be no obstructions at both air inlet and outlet of indoor and outdoor units for
maintaining well air ventilation.
● When installing indoor unit, make sure that the hanging parts at top are strong enough to
stand the weight of unit.
2.3.2 Matters Need Attention
● Before installation, make sure that the power supply comply with nameplate and check the
security of the power supply.
● Do not use or place combustible and explosive gas or liquid near the air conditioner.
● Do not attempt to install Air Conditioner by yourself to guarantee the air Conditioner can be
permanent use.
● In the event of malfunction(burning smell, etc.),stop operation immediately and turn off the
power switch.
● Do not insert fingers or objects into the outlet port or inlet grillers.
● Do not check or repair the air Conditioner when it is running.
● Do not sprinkle water on the air Conditioner or operate it with wet hands.
● Do not climb or place objects on the air conditioner.
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2.4 Installation Recommendations
NOTE: In some cases noise in the living area has been traced to gas pulsations from improper
installation of equipment.
1).  Locate unit away from windows, patios, decks, etc. where unit operation sound may disturb
customer.
2).  Ensure that vapor and liquid tube diameters are appropriate for unit capacity.
3).  Run refrigerant tubes as directly as possible by avoiding unnecessary turns and bends.
4).  Leave some slack between structure and unit to absorb vibration.
5).  When passing refrigerant tubes through the wall, seal opening with RTV or other pliable
silicon--based caulk.(See Fig. 5.)
6).  Avoid direct tubing contact with water pipes, duct work, floor joists, wall studs, floors, and
walls.
7).  Do not suspend refrigerant tubing from joists and studs with a rigid wire or strap which comes
in direct contact with tubing. (See Fig. 5.)
8).  Ensure that tubing insulation is pliable and completely surrounds vapor tube.
9).  When necessary, use hanger straps which are 1 in. wide and conform to shape of tubing
insulation. (See Fig. 5.)
10).  Isolate hanger straps from insulation by using metal sleeves bent to conform to shape of
insulation.
When outdoor unit is connected to factory--approved indoor unit, outdoor unit contains system
refrigerant charge good for 25 ft.
For proper unit operation, check refrigerant charge using charging information located on
control box cover and/or in the Check Charge section of this instruction.
NOTE: Avoid contact between tubing and structure
INDOOR WALL
OUTDOOR WALL
CAULK
LIQUID TUBE
VAPOR TUBE
INSULATION
THROUGH THE WALL
JOIST
HANGER STRAP
(AROUND VAPOR
TUBE ONLY)
INSULATION
VAPOR TUBE
1”MIN.
SUSPENSION
LIQUID TUBE
Fig.5 – Connecting Tubing Installation
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3. Brazing Connections
3.1 Preparation the Line
Refer to Table 2 for field tubing diameters. The pipe must remain round. Do not crimp end of
the line.
Table 2. Refrigerant Line Set Inches (mm)
Model
Valve Field Connections
Liquid Line
Vapor Line
MAC13018
MHP13018
5/8 in. (16 mm)
MAC13024
MHP13024
MAC13030
MHP13030
MAC13036
3/8 in. (9.5 mm)
3/4 in. (19 mm)
MHP13036
MAC13042
MHP13042
7/8 in. (22 mm)
MAC13048
MHP13048
MAC13060
MHP13060
1/2 in. (12 mm)
Line set size matches
service valve connection
1-1/8 in. (28 mm)
Do not crimp service valve connector
whenpipe is smaller than connection
Fig.6
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3.2 Cap and Core Removal
Remove service cap and core from both the vapor and liquid line service ports.
Service port core
Service port core
Service port cap
Service port cap
Vapor line
service valve
Liquid line
service valve
Fig.7
3.3 Attach Gauge
Flow regulated nitrogen (at 1 to 2 psig) through the low−side refrigeration gauge set into the
liquid line service port valve, and out of the vapor line service port valve.
Use regulator to flow
nitrogen at 1 to 2 psig
Liquid line
Liquid line service valve
OUTDOOR
UNIT
INDOOR
UNIT
Vapor line
Vapor line service valve
Vapor service port must be open
to allow exit point for nitrogen
Fig.8
3.4 Braze Line Set
To help protect service valve seals during brazing,wrap water saturated cloths around
service valve bodies and copper tube stubs. Water saturated cloths must remain water saturated
throughout the brazing and cool−down process.
Braze line to the service valve.
When brazing line set to
service valves, point flame
away from service valve.
Water saturated
cloth
Fig.9
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3.5 Preparation for Next Step
After all connections have been brazed, disconnect manifold gauge set from service ports.
Apply water saturated cloths to both services valves to cool piping. Once piping is cool, remove all
water saturated cloths.Reinstall service cap and core.Refer to the unit installation instructions for
the next step in preparing the unit.
4. Check Piston
There is a piston located in outdoor condensing unit, please verify the piston size based on the
below table. When matching with air handler, please make sure replace this piston in air handler.
Table 3
OUTDOOR UNIT
INDOOR UNIT
PISTON KIT PART NO.
MAC13018
MAH13018
053
MAC13024
MAH13024
054
MAC13030
MAH13030
064
MAC13036
MAH13036
067
MAC13042
MAH13042
071
MAC13048
MAH13048
079
MAC13060
MAH13060
084
MHP13018
MAH13018
055
MHP13024
MAH13024
057
MHP13030
MAH13030
068
MHP13036
MAH13036
067
MHP13042
MAH13042
073
MHP13048
MAH13048
082
MHP13060
MAH13060
091
Fixed orifice
Liquid line orifice housing
Teflon ring
Distributor assembly
Liquid line assembly
(includes strainer)
Brass nut
Liquid line
Vapor line
Fig.10
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5. Operating Gauge Set and Service Valves
These instructions are intended as a general guide and do not supersede local codes in any
way. Consult authorities who have jurisdiction before installation.
5.1 Torque Requirements
When servicing or repairing heating, ventilating, and air conditioning components, ensure the
fasteners are appropriately tightened. Table 4 lists torque values for fasteners.
IMPORTANT
Only use Allen wrenches of sufficient hardness (50Rc −Rockwell Harness Scale minimum).
Fully insert the wrench into the valve stem recess.
Service valve stems are factory−torqued (from 9 ft−lbs for small
valves, to 25 ft−lbs for large valves) to prevent refrigerant loss during shipping and handling.
Using an Allen wrench rated at less than 50Rc risks rounding or breaking off the wrench, or
stripping the valve stem recess.
To prevent stripping of the various caps used, the appropriately sized wrench should be used
and fitted snugly over the cap before tightening.
Table 4. Torque Requirements
Parts
Recommended Torque
Service valve cap
8 ft.− lb.
11 NM
Sheet metal screws
16 in.− .lb
2 NM
Machine screws #10
28 in.− lb.
3 NM
Compressor bolts
90 in.− lb.
10 NM
Gauge port seal cap
8 ft.− lb.
11 NM
5.2 Using Manifold Gauge Set
When checking the system charge, only use a manifold gauge set that features low loss anti−
blow back fittings.
Manifold gauge set used with HFC−410A refrigerant systems must be capable of handling the
higher system operating pressures. The gauges should be rated for use with pressures of 0 − 800
psig on the high side and a low side of 30" vacuum to 250 psig with dampened speed to 500 psig.
Gauge hoses must be rated for use at up to 800 psig of pressure with a 4000 psig burst rating.
5.3 Operating Service Valves
The liquid and vapor line service valves are used for removing refrigerant, flushing, leak testing,
evacuating, checking charge and charging.
Each valve is equipped with a service port which has a factory−installed valve stem. Figure 11
provides information on how to access and operating both angle service valves.
5.4 Operating Angle Type Service Valve
1).  Remove stem cap with an appropriately sized wrench.
2).  Use a service wrench with a hex−head extension (3/16" for liquid line valve sizes and 5/16"
for vapor line valve sizes) to back the stem out counterclockwise as far as it will go.
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Unitary Ducted Split AC & HP
Service port cap
To outdoor unit
Service port core
( Valve stem shown closed)
Insert hex wrench here
(valve stem shown open)
Insert hex wrench here
To indoor unit
Stem cap
Service valve
(Back-seated opened)
Service valve
(Front-seated closed)
Fig.11
5.5 To Access Service Port
A service port cap protects the service port core from contamination and
serves as the primary leak seal.
1). Remove service port cap with an appropriately sized wrench.
2). Connect gauge set to service port.
3). When testing is completed, replace service port cap and tighten as follows
● With torque wrench: Finger tighten and torque cap per table 4.
● Without torque wrench: Finger tighten and use an appropriately sized
wrench to turn an additional 1/6 turn clockwise.
5.6 Reinstall Stem Cap
Stem cap protects the valve stem from damage and serves as the primary
seal. Replace the stem cap and tighten as follows:
● With Torque Wrench: Finger tighten and then torque cap per table 4.
● Without Torque Wrench: Finger tighten and use an appropriately sized
wrench to turn an additional 1/12 turn clockwise.
NOTE: A label with specific torque requirements may be affixed to the
stem cap. If the label is present, use the specified torque.
5.7 Install Liquid Line Filter Drier Indoor
Refer to Fig. 12 and install filter drier as follows:
1).  Braze 5 in. liquid tube to the indoor coil.
2).  Wrap filter drier with damp cloth.
3).  Braze filter drier to 5 in. long liquid tube from step 1.
4).  Connect and braze liquid refrigerant tube to the filter drier.
Fig.12—Liquid Line Filter Drier
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Unitary Ducted Split AC & HP
6. Recovering Refrigerant from Existing System
6.1 Disconnect Power
Disconnect all power to the existing outdoor unit at the disconnect switch or main fuse box/
breaker panel.
6.2 Connect Manifold Gauge Set
Connect a gauge set, clean recovery cylinder and a recovery machine to the service ports of
the existing unit. Use the instructions provided with the recovery machine to make the connections.
Main Fuse Box/Breaker Panel
Recovery Machine
Manifold Gauges
Low
Disconnect Switch
Clean Recovery Cylinder
High
Outdoor Unit
Fig.13
6.3 Recovering Refrigerant
Remove existing HCFC−410A refrigerant using one of the following procedures:
METHOD 1:
Us this method if the existing outdoor unit is not equipped with shut−off valves, or if the unit is
not operational and you plan to use the existing HCFC−410A to flush the system.
Remove all HCFC−410A refrigerant from the existing system. Check gauges after shutdown to
confirm that the entire system is completely void of refrigerant.
METHOD 2:
Use this method if the existing outdoor unit is equipped with manual shut−off valves, and you
plan to use new HCFC−410A refrigerant to flush the system.
The following devices could prevent full system charge recovery into the outdoor unit:
● Outdoor unit’s high or low−pressure switches (if applicable) when tripped can cycle the
compressor OFF.
● Compressor can stop pumping due to tripped internal pressure relief valve.
● Compressor has internal vacuum protection that is designed to unload the scrolls
(compressor stops pumping) when the pressure ratio meets a certain value or when the suction
pressure is as high as 20 psig. (Compressor suction pressures should never be allowed to go into
a vacuum. Prolonged operation at low suction pressures will result in overheating of the scrolls and
permanent damage to the scroll tips, drive bearings and internal seals.)
Once the compressor can not pump down to a lower pressure due to one of the above system
conditions, shut off the vapor valve. Turn OFF the main power to unit and use a recovery machine
to recover any refrigerant left in the indoor coil and line set.
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Unitary Ducted Split AC & HP
Perform the following task:
a.  Start the existing HCFC−410A system in the cooling mode and close the liquid line valve.
b.  Use the compressor to pump as much of the existing HCFC−410A refrigerant into the
outdoor unit until the outdoor system is full. Turn the outdoor unit main power OFF and use
a recovery machine to remove the remaining refrigerant from the system.
NOTE: It may be necessary to bypass the low pressure switches (if equipped) to ensure
complete refrigerant evacuation.
c.  When the low side system pressures reach 0 psig, close the vapor line valve.
d.  Check gauges after shutdown to confirm that the valves are not allowing refrigerant to flow
back into the low side of the system.
6.4 Leak Test Line Set and Indoor Coil
Fig.14—Leak Test
6.4.1 Connect Gauge Set
1).  Connect an HFC−410A manifold gauge set high pressure hose to the vapor valve service
port.
NOTE: Normally, the high pressure hose is connected to the liquid line port. However,
connecting it to the vapor port better protects the manifold gauge set from high pressure damage.
2). With both manifold valves closed, connect the cylinder of HFC−410A refrigerant to the center
port of the manifold gauge set.
NOTE: Later in the procedure, the HFC−410A container will be replaced by the nitrogen
container.
6.4.2 Test For Leaks
After the line set has been connected to the indoor and outdoor units, check the line set
connections and indoor unit for leaks. Use the following procedure to test for leaks:
1).  With both manifold valves closed, connect the cylinder of HFC−410A refrigerant to the center
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Unitary Ducted Split AC & HP
port of the manifold gauge set. Open the valve on the HFC−410A cylinder (vapor only).
2).  Open the high pressure side of the manifold to allow HFC−410A into the line set and indoor
unit. Weigh in a trace amount of HFC−410A. [A trace amount is a maximum of two ounces
(57 g) refrigerant or three pounds (31 kPa) pressure]. Close the valve on the HFC−410A
cylinder and the valve on the high pressure side of the manifold gauge set. Disconnect the
HFC−410A cylinder.
3).  Connect a cylinder of dry nitrogen with a pressure regulating valve to the center port of the
manifold gauge set.
4).  Adjust dry nitrogen pressure to 150 psig (1034 kPa). Open the valve on the high side of the
manifold gauge set in order to pressurize the line set and the indoor unit.
5).  After a few minutes, open one of the service valve ports and verify that the refrigerant added
to the system earlier is measurable with a leak detector.
6).  After leak testing disconnect gauges from service ports.
6.5 Evacuating Line Set and Indoor Coil
Fig.15—Evacuating System
6.5.1 Connect Gauge Set
NOTE : Remove cores from service valves (if not already done).
1).  Connect low side of manifold gauge set with 1/4 SAE in−line tee to vapor line service valve
2).  Connect high side of manifold gauge set to liquid line service valve
3).  Connect micron gauge available connector on the 1/4 SAE in−line tee.
4).  Connect the vacuum pump (with vacuum gauge) to the center port of the manifold gauge
set.
The center port line will be used later for both the HFC−410A and nitrogen containers.
6.5.2 Connect Gauge Set
1).  Open both manifold valves and start the vacuum pump.
2).  Evacuate the line set and indoor unit to an absolute pressure of 23,000 microns (29.01
inches of mercury).
NOTE : During the early stages of evacuation, it is desirable to close the manifold gauge valve
at least once. A rapid rise in pressure indicates a relatively large leak. If this occurs, repeat the leak
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Unitary Ducted Split AC & HP
testing procedure.
NOTE: The term absolute pressure means the total actual pressure within a given volume
or system, above the absolute zero of pressure. Absolute pressure in a vacuum is equal to
atmospheric pressure minus vacuum pressure.
3).  When the absolute pressure reaches 23,000 microns (29.01 inches of mercury), perform the
following:
● Close manifold gauge valves
● Close valve on vacuum pump
● Turn off vacuum pump
● Disconnect manifold gauge center port hose from vacuum pump
● Attach manifold center port hose to a dry nitrogen cylinder with pressure regulator set to 150
psig (1034 kPa) and purge the hose.
● Open manifold gauge valves to break the vacuum in the line set and indoor unit.
● Close manifold gauge valves.
4).  Shut off the dry nitrogen cylinder and remove the manifold gauge hose from the cylinder.
Open the manifold gauge valves to release the dry nitrogen from the line set and indoor unit.
5).  Reconnect the manifold gauge to the vacuum pump, turn the pump on, and continue to
evacuate the line set and indoor unit until the absolute pressure does not rise above 500
microns (29.9 inches of mercury) within a 20−minute period after shutting off the vacuum
pump and closing the manifold gauge valves.
6).  When the absolute pressure requirement above has been met, disconnect the manifold hose
from the vacuum pump and connect it to an upright cylinder of HFC−410A refrigerant. Open
the manifold gauge valve 1 to 2 psig in order to release the vacuum in the line set and indoor
unit.
7).  Perform the following:
● Close manifold gauge valves.
● Shut off HFC−410A cylinder.
● Reinstall service valve cores by removing manifold hose from service valve.
Quickly install cores with core tool while maintaining a positive system pressure.
● Replace stem caps and secure finger tight, then tighten an additional one−sixth (1/6) of a turn
as illustrated.
7. Electrical
In the U.S.A., wiring must conform with current local codes and the current National Electric
Code (NEC). In Canada, wiring must conform with current local codes and the current Canadian
Electrical Code (CEC).
Refer to the furnace or air handler installation instructions for additional wiring application
diagrams and refer to unit nameplate for minimum circuit ampacity and maximum overcurrent
protection size.
24VAC TRANSFORMER
Use the transformer provided with the furnace or air handler for low-voltage control power
(24VAC − 40 VA minimum).
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7.1 Size Circuit And Install Disconnect Switch
Refer to the unit nameplate for minimum circuit ampacity, and maximum fuse or circuit breaker
(HACR per NEC). Install power wiring and properly sized disconnect switch.
Main Fuse Box/Breaker Panel
Disconnect Switch
Fig.16
NOTE: Units are approved for use only with copper conductors. Ground unit at disconnect
switch or to an earth ground.
7.2 Install Thermostat
Install room thermostat (ordered separately) on an inside wall approximately in the center of
the conditioned area and 5 feet (1.5m) from the floor. It should not be installed on an outside wall or
where it can be affected by sunlight or drafts.
Fig.17
NOTE: 24VAC, Class II circuit connections are made in the control panel.
7.3 Unit Low Voltage Connections
High voltage field wiring
Low voltage (24v) field wiring
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Table 5
WIRE RUN LENGTH
AWG#
INSULATION TYPE
LESS THAN 100’ (30 METERS)
18
Temperature Rating
MORE THAN 100’ (30 METERS)
16
35°C Minimum
A Run 24VAC control wires through cutout with grommet.
B Run 24VAC control wires through wire tie.
C Make 24VAC control wire connections.
NOTE: Wire tie provides low voltage wire strain relief and to maintain separation
of field low and high voltage circuits
NOTE: For proper voltages, select thermostat wire (control wires)gauge per
table above.
NOTE: Do not bundle any excess 24VAC control wires inside control box.
7.4 Unit High Voltage Connections
A Run HIGH VOLTAGE control wires through cutout with grommet.
B Make HIGH VOLTAGE control wires connections.
C Tighten wire tie to security HIGH VOLTAGE control wiring.
NOTE: Any excess high voltage field wiring should be trimmed
and secured away from any low voltage field wiring
NOTE: To facilitate a conduit, a cutout is located in the bottom of the control
box. Connect conduit to the control box using a proper conduit fitting.
NOTE: The signal line of the wired controller must be separated from the power
line and the connecting line between the indoor unit and the outdoor unit.
Important Electric Data
Table 6
Fan
Motor
Compressor
Model
Power Supply
Qty.
RLA
LRA
FLA
Fuse/Breaker
Capacity
Min. Power
Supply Cord
V/Ph/Hz
-
A
A
A
A
AWG
MAC13018
208/230/1/60
1
7.9
38
1.2
15
AWG16
MAC13024
208/230/1/60
1
9.8
53
1.2
20
AWG14
MAC13030
208/230/1/60
1
12.6
71
1.2
25
AWG12
MAC13036
208/230/1/60
1
15.08
64
1.7
35
AWG12
MAC13042
208/230/1/60
1
21.5
105
1.7
50
AWG10
MAC13048
208/230/1/60
1
21
115
1.7
45
AWG10
MAC13060
208/230/1/60
1
25
150
2.1
50
AWG8
MHP13018
208/230/1/60
1
7.5
38
0.8
15
AWG16
MHP13024
208/230/1/60
1
9.8
53
1.2
20
AWG14
MHP13030
208/230/1/60
1
12.5
71
0.7
25
AWG12
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17
Unitary Ducted Split AC & HP
MHP13036
208/230/1/60
1
15.08
64
1.7
35
AWG12
MHP13042
208/230/1/60
1
17
112
1.7
35
AWG10
MHP13048
208/230/1/60
1
21
115
1.7
45
AWG10
MHP13060
208/230/1/60
1
24.5
134
2.3
50
AWG8
Electric Wiring Design
Model:MAC13018; MAC13024; MAC13030; MAC13036; MAC13042;
MAC13048; MAC13060.
POWER
208/230V
L1
1PH 60HZ
L2
Ground
T1
T2
L1
L2
C
C
R
R
W1
Y1
Y1
O
THERMOSTAT
G
Fig.18
Model: MHP13018; MHP13024; MHP13030; MHP13036.
L1
T1
L2
T2
L1
POWER
208/230V
1PH 60HZ
L2
Ground
KM
G
XT2
C
Outdoor
Unit
R
R
Y1
Y1
W1
W1
Fig.19
Model: MHP13042; MHP13048; MHP13060.
For more details visit www.MrCool.com
18
THERMOSTAT
G
C
Unitary Ducted Split AC & HP
L1
XT1
POWER
208/230V
1PH 60HZ
L1
L2
L2
Ground
G
Outdoor
Unit
C
R
R
Y1
Y1
O
W1
O
W1
THERMOSTAT
G
XT2
C
Fig.20
18-36k Circuit Diagram
Model:MAC13018; MAC13024; MAC13030; MAC13036.
T2
A1
KM
A2
OUTDOOR UNIT
POWER
G
W7
RT
X12
P
W5
BU
WH
WH
P
C
HERMFAN
W1 W2
W3
R
COMP
~
X8
G
CAPACITOR
G
R
W12
W11
W10
XT
Y1
R
C
24V~INPUT
24V~INPUT
COM
X7
W6
BN
S
Compressor
AP
C
BK
RT
discharge temperature
sensor
AP
MAIN BOARD
KM
AC Contactor
M
~
W4
X3
LP
RD
C
OG
CN3
X10
HP
50K
G
YEGN
Fan motor
G
Fig.21
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19
Y1
R
C
Lug Plate 1
T1
L2
THERMOSTAT
L1
Unitary Ducted Split AC & HP
42-60k Circuit Diagram
Model:MAC13042; MAC13048; MAC13060.
THERMOSTAT
~
Lug Plate 1
OUTDOOR UNIT
~
Fig.22
18-36k Circuit Diagram
Model: MHP13018; MHP13024; MHP13030; MHP13036.
KM
L1
T1
L2
T2
G
A2
W11
20K
RT2
K2
(AC-L)
W15
4YV
XT1
P
W5
1
HP
P
LP
C
HERM
W2
W1
W3
BU
WH
WH
OG
FAN
C
RD
BN
COMP
G
X3
X2
X10
AP
X1
R
X8
X7
C
K2
(OFAN-H)
K5
(OFAN-L)
BK
~
Compressor
XT2
CN5
W21
W20
W19
W18
W17
Y1
O
W1
R
C
24V~INPUT
24V~INPUT
24V~INPUT
24V~INPUT
COM
Y1
O
W1
R
C
O1
X14
W22
W23
O
W14
KM-L2
XT1
M
~
G
W4
CN3
W13
CAPACITOR
S
CN1
X13
W12
2
R
R
20K
X12
THERMOSTAT
W16
W25
50K
θ
θ
RT1
G
Fan motor
YEGN
Notes:
'O1'is used when under testing,
connected with 'O' of indoor
unit, usually suspended.
G
Fig.23
For more details visit www.MrCool.com
20
AP MAIN BOARD
RT1 Pipe temperature Sensor
discharge temperature
RT2 sensor
4YV
4-WAY VALVE
KM
AC Contactor
Lug Plate 1
KM
Indoor
A1
OUTDOOR UNIT
POWER
Unitary Ducted Split AC & HP
42-60k Circuit Diagram
Model:MHP13042; MHP13048; MHP13060.
Fig.24
8. System Refrigerant
This section outlines procedures for:
● Connecting gauge set for testing and charging.
● Adding or removing refrigerant.
8.1 Gauge Set (Cooling Only)
Connections for testing and charging.
A Close manifold gauge set valves and connect the center hose to a cylinder of HFC−410A.
Set for liquid phase charging.
B Connect the manifold gauge set’s low pressure side to the suction line service port.
C Connect the manifold gauge set’s high pressure side to the liquid line service port.
D Position temperature sensor on vapor line near liquid line service port.
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21
Unitary Ducted Split AC & HP
Figure 25. Gauge Set Setup and Connections for cooling only
8.2 Gauge Set (Heat Pump)
Connections for testing and charging.
A Close manifold gauge set valves and connect the center hose to a cylinder of HFC−410A.
Set for liquid phase charging.
B Connect the manifold gauge set’s low pressure side to the true suction port.
C Connect the manifold gauge set’s high pressure side to the liquid line service port.
D Position temperature sensor on the suction line near the compressor.
Figure 26. Gauge Set Setup and Connections for heat pump
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22
Unitary Ducted Split AC & HP
8.3 Weigh In
Calculating system charge for outdoor unit void of charge
If the system is void of refrigerant, first, locate and repair any leaks and then weigh in the
refrigerant charge into the unit. To calculate the total refrigerant charge:
Amount specified
on nameplate
Adjust amount for variation
+ in line set length listed on = Total charge
line set length table below
Refrigerant Charge per Line Set Length:
Table 7
Outdoor Unit
COOLING ONLY
HEAT PUMP
Liquid Line
Set Diameter
Ounces per 5 feet (g per 1.5 m)
adjust from 25 feet (7.6 m) line set*
3/8" (9.5 mm)
1.6 ounce per 5 feet (45g per 1.5 m)
1/2"(12.7 mm)
3.2 ounce per 5 feet (90g per 1.5 m)
3/8" (9.5 mm)
2.9 ounce per 5 feet (81g per 1.5 m)
1/2"(12.7 mm)
5.9 ounce per 5 feet (165g per 1.5 m)
*If line length is greater than 25 ft. (7.6 m), add this amount. If line length is less than 25 ft. (7.6
m), subtract this amount.
NOTE: Insulate liquid line when it is routed through areas where the surrounding ambient
temperature could become higher than the temperature of the liquid line or when pressure drop is
equal to or greater than 20 psig.
NOTE: The above nameplate is for illustration purposes only. Go to actual nameplate on
outdoor unit for charge information.
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23
Unitary Ducted Split AC & HP
START: Measure outdoor ambient temperature
40℉(4.4℃) and above
39℉(3.8℃) and below
ABOVE or BELOW
USE WEIGH-IN METHOD
Weigh-in or remove refrigerant
based upon line length
S H°(Superheat) Values (+/ ℉)
℉*
Wet Bulb (air entering indoor coil)
50
55
60
65
70
75
80
40
15
21
29
35
43
49
56
45
13
19
27
34
41
47
54
50
11
17
25
32
39
45
52
55
9
15
23
31
38
43
49
60
7
13
21
28
35
41
47
65
-
11
19
25
33
39
45
70
75
-
8
-
16
12
22
19
30
28
37
35
43
40
80
-
-
8
16
25
33
37
85
-
-
-
13
22
31
35
90
-
-
-
11
20
29
33
95
-
-
-
8
18
27
31
100
-
-
-
-
16
26
29
105
-
-
-
-
13
24
28
110
-
-
-
-
11
22
27
115
-
-
-
-
8
20
25
MORE or LESS
If value is LESS than
shown, then REMOVE
refrigerant.
If refrigerant is
REMOVED, retest
to confirm that unit
is properly charged.
If value is MORE than shown,
then ADD refrigerant.
Figure 27. HFC−410A Superheat RFC Method
For more details visit www.MrCool.com
24
If refrigerant is ADDED,
retest to confirm that unit
is properly charged.
Unitary Ducted Split AC & HP
Table 8. Normal Operating Pressures − Liquid +10 and Vapor +5 PSIG* (All Models)
MHP13018
MHP13024
MHP13030
MHP13036
Liquid / Vapor
Liquid / Vapor
Liquid / Vapor
Liquid / Vapor
60(15)
346/139
352 / 138
338 / 137
350 / 134
50(10)
323/117
331/114
334/112
331/117
40(4)
306/98
304/99
312/93
313/97
30(-1)
278/84
299/80
302/74
298/83
20(-7)
273/66
283/66
280/53
284/66
65(18)
226/140
233/137
238/138
220/138
70(21)
244/141
252/138
263/139
236/140
75(24)
263/142
271/140
279/139
256/141
80(27)
283/143
292/141
299/140
276/142
85(29)
302/144
314/142
324/141
298/143
90(32)
328/145
338/143
340/142
321/144
℉ (℃ ) **
Heating
Cooling
95(35)
351 / 146
361 / 145
375 / 145
344 / 144
100(38)
376 / 147
387 / 146
397 / 145
369 / 146
105(41)
402 / 148
412 / 147
424 / 147
394 / 147
110(43)
430 / 149
441 / 148
454 / 150
421 / 148
115(46)
465 / 150
471 / 151
485 / 150
449 / 149
*IMPORTANT—These are most popular match−up pressures. Indoor match up, indoor air quality, and
indoor load cause pressures to vary.
**Temperature of the air entering the outside coil.
℉ (℃ ) **
MHP13042
MHP13048
MHP13060
Liquid / Vapor
Liquid / Vapor
Liquid / Vapor
Heating
60(15)
373 / 139
355/130
351/117
50(10)
363/117
336/113
333/105
40(4)
348/97
315/88
316/88
30(-1)
336/74
296/72
308/70
20(-7)
322/64
286/64
300/61
Cooling
65(18)
223/125
231/136
243/136
70(21)
241/130
248/139
263/137
75(24)
261/134
271/140
282/138
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25
Unitary Ducted Split AC & HP
80(27)
282/138
291/142
306/139
85(29)
302/139
312/143
327/140
90(32)
326/140
335/144
351/141
95(35)
349 / 141
359 / 145
376 / 142
100(38)
374 / 142
384 / 146
401 / 143
105(41)
399 / 143
411 / 148
426 / 145
110(43)
428 / 145
439 / 149
452 / 146
115(46)
455 / 146
468 / 150
484 / 148
*IMPORTANT—These are most popular match−up pressures. Indoor match up, indoor air quality, and
indoor load cause pressures to vary.
**Temperature of the air entering the outside coil.
Table 9. HFC−410A Temperature (°F) − Pressure (Psig)
℉
Psig
℉
Psig
℉
Psig
℉
Psig
℉
Psig
℉
Psig
℉
Psig
℉
Psig
32
100.8
48
137.1
63
178.5
79
231.6
94
290.8
110
365.0
125
445.9
141
545.6
33
102.9
49
139.6
64
181.6
80
235.3
95
295.1
111
370.0
126
451.8
142
552.3
34
105.0
50
142.2
65
184.3
81
239.0
96
299.4
112
375.1
127
457.6
143
559.1
35
107.1
51
144.8
66
187.7
82
242.7
97
303.8
113
380.2
128
463.5
144
565.9
36
109.2
52
147.4
67
190.9
83
246.5
98
308.2
114
385.4
129
469.5
145
572.8
37
111.4
53
150.1
68
194.1
84
250.3
99
312.7
115
390.7
130
475.6
146
579.8
38
113.6
54
152.8
69
197.3
85
254.1
100
317.2
116
396.0
131
481.6
147
586.8
39
115.8
55
155.5
70
200.6
86
258.0
101
321.8
117
401.3
132
487.8
148
593.8
40
118.0
56
158.2
71
203.9
87
262.0
102
326.4
118
406.7
133
494.0
149
601.0
41
120.3
57
161.0
72
207.2
88
266.0
103
331.0
119
412.2
134
500.2
150
608.1
42
122.6
58
163.9
73
210.6
89
270.0
104
335.7
120
417.7
135
506.5
151
615.4
43
125.0
59
166.7
74
214.0
90
274.1
105
340.5
121
423.2
136
512.9
152
622.7
44
127.3
60
169.6
75
217.4
91
278.2
106
345.3
122
428.8
137
519.3
153
630.0
45
129.7
61
172.6
76
220.9
92
282.3
107
350.1
123
434.5
138
525.8
154
637.5
46
132.2
62
175.4
77
224.4
93
286.5
108
355.0
124
440.2
139
532.4
155
645.0
47
134.6
78
228.0
109
360.0
140
539.0
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26
Unitary Ducted Split AC & HP
9. Unit Control
9.1 Mainboard Description
Pressure switch
circuit connections
24V terminal
strip connections
Sensor plug in
(Discharge sensor)
24V terminal
strip connections
+12V common
terminal
Diagnostic leds
Fig.28 Mainboard Description for cooling only
Temp. Sensors plug in
+12V common
terminal
Pressure switch
circuit connections
Disagnostic
display
24V terminal
strip connections
24V terminal strip connections
Connections for fan motor
Fig.29 Mainboard Description for Heat pump unit
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27
Unitary Ducted Split AC & HP
9.2 Terminal Description
Table 10. Demand Control Board Description for cooling only unit
ID
Description
X12(Y-OUT)
24 VAC output connection for compressor operation
X7(LPP)
Connection for low−pressure switch
X10(HPP)
Connection for high−pressure switch
X3(Y)
24 VAC input for compressor operation
CN3(T-PIPE)
Connection for discharge temperature sensor.
X16(C)
24 VAC system common
X15(R)
24 VAC system power input
X8(+12V)
Connection for low−pressure switch Connection for high−pressure switch
Table 11. Demand Control Board Description for Heat pump unit
ID
Description
X1(W-OUT)
Auxiliary electrical heater output
X2(O)
Connection for detecting the 24VAC control signal of 4-way valve
X3(Y)
Connection for detecting the 24VAC signal for compressor
X7(LPP)
Connection for low pressure switch
X8(+12V)
Connection for low pressure switch, Connection for high pressure switch
X10(HPP)
Connection for high pressure switch
X12(Y-OUT)
24 VAC output interface for compressor operation
X13(O-OUT)
24 VAC output interface for 4-way valve operation
X14(N)
220 VAC N input of fan motor
X15(R)
24 VAC system power input
X16(C)
24 VAC system common
CN1(T-DF)
Connection for temp.sensor of condenser
CN2(OUTROOM)
Connection for ambient temp.sensor
CN3(T-PIPE)
Connection for discharge temp.sensor
CN5(TUBE)
Connect 20k fixed resistance into reserved interface
K2-2(OFAN-H)
220VAC output for high speed of fan motor
K2-4(AC-L)
220VAC L input for high speed of fan motor
K5-2(OFAN-L)
220VAC output for low speed of fan motor
K5-4(AC-L)
220VAC L input for low speed of fan motor
For more details visit www.MrCool.com
28
Unitary Ducted Split AC & HP
9.3 Control Flowchart
Cooling Operation
Heating Operation
Power
On
Power
On
Choo se cooling model
Choo se heaingt
model
Indoo r fan run
N
Satisfying open
comp. condition
Satisfying open
Comp. condition
Y
N
Comp. and outdoo r
fan run
Y
Comp. and outdoo r
fan run
Temp of indoo r
≥Set temp
Temp of indoo r
N
N
≤Set temp
Y
Y
Comp. and
outdoo r fan stop
Comp. and
outdoo r fan stop
Y
Comp. stop
for 3 min
Y
N
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29
Comp. stop
for 3 min
N
Unitary Ducted Split AC & HP
9.4 Error Analysis
COOLING ONLY
DEMAND CONTROL BOARD DIAGNOSTICS
The state (Off, On, Flashing) of two LEDs on the control board (DS1 [Red] and DS2 [Red]) indicate
diagnostics conditions that are described in table 12. See table 12 to determine control board
operational conditions and to diagnose cause and solution to problems.
Table 12. Demand Control board Diagnostic LEDs
Origin of
DS1 Red
DS2 Red
Trouble Case
Measure
Trouble
OFF
Power
problem
OFF
No power
(24V) to
demand
control board
terminals
R and C
or demand
control board
failure.
1 Check control transformer power
(24V).
2 If power is available to demand
control board and LED(s) do not
light, replace control board.
FAULT and LOCKOUT CODES (Each fault adds 1 strike to that code’s counter; 3 strikes per 30
minutes = LOCKOUT)
0.5s
Circulating
Flash
OFF
Actuation of
high pressure
switch
OFF
0.5s
Circulating
flash
Actuation of
low pressure
switch
High pressure
switch
Abnormality is detected when the
contact of the high pressure switch
opens for 3 sec. The system will
be shut down. The unit will report
this fault. For the first two faults
within 30 minutes, the unit can be
recovered automatically. If over
three times, the unit cannot be
recovered automatically.
Low pressure
switch
When the unit runs more than 4
minutes or does not run, the low
pressure switch opens for more
than3sec and the system will be
shut down..The unit will report
this fault. For the first two faults
within 30 minutes, the unit can be
recovered automatically. If over
three times, the unit cannot be
recovered automatically.
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30
Unitary Ducted Split AC & HP
0.5s
Circulating
Flash
Continuous
Light
Air discharge
hightemperature
protection of
compressor
Exhaust overtemperature
Protection
The exhaust temperature is higher
than 125°C for more than 5s, the
system will be shut down. After
stopping the compressor for 3
mins, if the exhaust temperature
is lower than 90°C for more than
5s, the compressor will re-start.
For the first two faults within 30
minutes, the unit can be recovered
automatically. If over three times,
the unit cannot be recovered
automatically.
Continuous
Light
OFF
Malfunction
of exhaust
Temp. Sensor
Exhaust
temperature
sensor
If the exhaust temperature
sensor is detected of open circuit
5 seconds successively after
the compressor is started for 3
minutes or short circuit 5 seconds
successively at any time The
system will be shut down. After the
fault is eliminated, the system can
automatically resume to operation
0.5s
Circulating
Flash
0.5s
Circulating
flash
Normal
operation
Unit operating
normally or
in standby
mode.
None required.
HEAT PUMP
Fault Display on the Dual 8 Numeral Tube of Outdoor Mainboard
Malfunction
code
Trouble case
E1
Actuation
of high
pressure
switch
E3
Actuation of
low pressure
switch
Origin of
trouble signal
Measure
High pressure
switch
Abnormality is detected when the contact of the
high pressure switch opens for 3 sec. The system
will be shut down. The unit will report this fault. For
the first two faults within 30 minutes, the unit can
be recovered automatically. If over three times, the
unit cannot be recovered automatically.
Low pressure
switch
When the unit runs more than 4 minutes or does
not run, the low pressure switch opens for more
than3sec and the system will be shut down. The
unit will report this fault. For the first two faults
within 30 minutes, the unit can be recovered
automatically. If over three times, the unit cannot be
recovered automatically.
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31
Unitary Ducted Split AC & HP
Exhaust overtemperature
protection
The exhaust temperature is higher than 125°C for
more than 5sec, the system will be shut down. After
stopping the compressor for 3 mins, if the exhaust
temperature is lower than 90°C for more than 5
sec, the compressor will re-start. For the first two
faults within 30 minutes, the unit can be recovered
automatically. If over three times, the unit cannot be
recovered automatically.
F2
Malfunction
of condenser
temperature
thermistor
Condenser
temperature
thermistor
Malfunction of condenser temperature thermistor
is detected when there is a short circuit or an open
circuit in the condenser temperature thermistor for
more than 5 sec. The system will be shut down. The
reset for the malfunction of condenser temperature
thermistor is automatic.
F3
Malfunction
of outdoor
ambient
temperature
thermistor
Outdoor
ambient
temperature
thermistor
Malfunction outdoor ambient temperature thermistor
is detected when there is a short circuit or an
open circuit in the outdoor ambient temperature
thermistor for more than 5 sec. The system will
be shut down. The reset for the malfunction of
condenser temperature thermistor is automatic.
F4
Malfunction
of Exhaust
Temp.
Sensor
Exhaust
temperature
sensor
If the exhaust temperature sensor is detected
of open circuit 5 seconds successively after the
compressor is started for 2 minutes or short circuit
5 seconds successively at any time .The system
will be shut down. After the fault is eliminated, the
system can automatically resume to operation.
oN
Normal
operation
Unit operating
normally or
in standby
mode.
H1
Defrost
operation
Unit operating
in defrost
E4
Air discharge
hightemperature
protection of
compressor
None required.
None required.
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32
Unitary Ducted Split AC & HP
9.5 Setting on Defrost Control PCB (for Heat Pump unit only)
There are 5 different defrost control setting you can choose by change the dip switch located
on Defrost Control PCB.
ON
12
DIP
000
ON
3
12
DIP
001
ON
3
DIP
ON
12
3
010
Fig.30
Table 13
12
DIP
011
ON
3
12
DIP
100
3
Without Outdoor Ambient
Sensor installed
Dip Switch Setting
000
001
010
011
100
t(min)
44
44
60
90
30
T1
28 ℉
23 ℉
32 ℉
32 ℉
32 ℉
T2
59 ℉
59 ℉
68 ℉
68 ℉
68 ℉
t-----------Accumulation of compressor running time
T1----------Initiation Coil Temperature
T2---------Termination Coil Temperature
The factory default setting is “000”. After the compressor consecutively runs for 44 minutes,
the defrost cycle will be initiated if the sensor detects the coil temperature ≤ 28 F for consecutive
1 minute. The defrost cycle will be terminated either the coil temperature reach 59 F or the defrost
cycle reach 15 minutes.
Defrost Cycle: when the system running in heat pump mode, after the compressor has been
running for “t” minutes continuously, the defrost cycle start if the defrosting temp sensor has been
in T1 degree or under T1 degree for 1 minute continuously. During the defrost cycle, the reversing
valve is energized, the outdoor fan stops running and the auxiliary electric heating is energized.
The defrost cycle will be terminated if defrost cycle reach 15 minutes or the coil sensor detects the
coil temperature over T2 degree.
9.6 Manually Defrost Cycle
There is a Manually Defrost Button located on the Defrost Control PCB, by press this button,
the system will go to defrost cycle right away to melt the ice on the coil.
For more details visit www.MrCool.com
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For more details visit www.MrCool.com