Heat Controller A-VMH18DC-1 Service User manual

Heat Controller, Inc. • 1900 Wellworth Ave. • Jackson, MI 49203 • [phone] • www.heatcontroller.com
SERVICE MANUAL
Inverter Flex Multi-Zone
Ductless Mini Split
Outdoor Section
A-VMH18DC-1
A-VMH27TC-1
A-VMH36QC-1

2
Service Manual VMH SerieS Heat Controller, Inc.
CONTENTS
1.General Information of Outdoor Units........................................................... 3
2. Features........................................................................................................... 4
3. Dimensions ..................................................................................................... 5
4. Wiring Diagram............................................................................................... 6
5. Refrigeration Cycle Diagram ......................................................................... 8
6. Indoor unit Combinations............................................................................ 10
7. Installation Details........................................................................................ 11
8. Electronic Control Function ........................................................................ 20
9. Troubleshooting ........................................................................................... 25

3
Heat Controller, Inc. VMH SerieS Service Manual
2
1. General information of Outdoor Units
Model name Dimension mm(in) Compressor
A-VMH18DC-1 845x320x700(33.3x12.6x27.6) DA130S1C-20FZ
A-VMH27TC-1 845x320x700(33.3x12.6x27.6) DA150S1C-20FZ
A-VMH36QC-1 990x345x965(39x13.6x38) TNB306FPGMC-L

4
Service Manual VMH SerieS Heat Controller, Inc.
3
2．Features
The hydrophilic fin is corrosion resistant and improves heating efficiency in heat mode by absorbing the water on
its surface and by spreading the water instead of forming water droplets.
Operates only in heating mode except during defrosting.
Compressor crankcase heater
It protects the valves and prevents water from dripping in the cabinet.
Outdoor unit
Power relay control
Hydrophilic aluminum fin
Anti-rust cabinet
Valve protection cover
4 way valve control
Low noise air flow system
Discharge pipe temperature protection

5
Heat Controller, Inc. VMH SerieS Service Manual
4
3. Dimensions
mm(in)
Model W D H W1 A B
A-VMH18DC-1 845((33.3) 320(12.6) 700(27.6) 908(35.7) 560(22) 335(13.2)
A-VMH24TC-1
A-VMH36QC-1 990(39) 345(13.6) 965(38) 1075(42.3) 624(24.6) 366(14.4)

6
Service Manual VMH SerieS Heat Controller, Inc.
5
4. Wiring Diagram
4.1 A-VMH18DC-1
4.2 A-VMH27TC-1

7
Heat Controller, Inc. VMH SerieS Service Manual
6
4.3 A-VMH36QC-1

8
Service Manual VMH SerieS Heat Controller, Inc.
7
5. Refrigeration Cycle Diagram
8.1 Refrigeration circuit drawing of inverter dual zone: A-VMH18DC-1
LIQUID VALVE A
GAS VALVE A
HEAT
EXCHANGE
(EVAPORATOR)
HEAT
EXCHANGE
(CONDENSER)
Compressor
4-WAY VALVE
COOLING
HEATING
T2 Evaporator
temp. sensor
T1 Room
temp. sensor
T3
Condenser
temp. sensor
T5 Discharge
temp. sensor
T4 Ambient
temp. sensor
INDOOR OUTDOOR
EXV A CAPILIARY A
CHECK VALVE
CAPILIARY TUBE
EXV B CAPILIARY B
LIQUID VALVE B
GAS VALVE B
Accumulator
5.2 Refrigeration circuit drawing of inverter tri-zone: A-VMH27TC-1
LIQUID VALVE A
GAS VALVE A
HEAT
EXCHANGE
(EVAPORATOR)
HEAT
EXCHANGE
(CONDENSER)
Compressor
4-WAY VALVE
COOLING
HEATING
T2 Evaporator
temp. sensor
T1 Room
temp. sensor
T3
Condenser
temp. sensor
T5 Discharge
temp. sensor
T4 Ambient
temp. sensor
INDOOR OUTDOOR
EXV A CAPILIARY A
CHECK VALVE
CAPILIARY TUBE
EXV B CAPILIARY B
LIQUID VALVE B
GAS VALVE B
EXV C CAPILIARY C
LIQUID VALVE C
GAS VALVE C
Accumulator

9
Heat Controller, Inc. VMH SerieS Service Manual
8
8.3 Refrigeration circuit drawing of inverter Quad-zone: A-VMH36QC-1
LIQUID VALVE A
GAS VALVE A
HEAT
EXCHANGE
(EVAPORATOR)
HEAT
EXCHANGE
(CONDENSER)
Compressor
4-WAY VALVE
COOLING
HEATING
T2 Evaporator
temp. sensor
T1 Room
temp. sensor
T3
Condenser
temp. sensor
T5 Discharge
temp. sensor
T4 Ambient
temp. sensor
INDOOR OUTDOOR
EXV A CAPILIARY A
CHECK VALVE
CAPILIARY TUBE
EXV B CAPILIARY B
LIQUID VALVE B
GAS VALVE B
EXV C CAPILIARY C
LIQUID VALVE C
GAS VALVE C
EXV D CAPILIARY D
LIQUID VALVE D
GAS VALVE D
Accumulator
High pressure
switch
Low pressure
switch

10
Service Manual VMH SerieS Heat Controller, Inc.
9
6. Indoor units combination
NOTE: The total capacity of indoor air handlers can not exceed the nominal capacity of the outdoor unit.
The minimum quantity of indoor air handlers is one on any outdoor unit, whether it is a dual, tri, or quad
zone.
6.1 Indoor unit combinations for A-VMH18DC-1
Comb.
Combinations
Unit A
Unit B
Dual(1x1)
9k
—
12k
—
18k
—
Dual (1x2)
9k
9k
9k
12k
6.2Indoor unit combinations A-VMH27TC-1
Comb.
Combinations
Unit A
Unit B
Unit C
TRI (1x1)
9k
—
—
12k
—
—
18k
—
—
TRI (1x2)
9k
9k
—
9k
12k
—
9k
18k
—
12k
12k
—
TRI (1x3)
9k
9k
9k
6.3Indoor unit combinations A-VMH36QC-1
Comb.
Combinations
Unit A
Unit B
Unit C
Unit D
QUA (1x1)
9k
—
—
—
12k
—
—
—
18k
—
—
—
QUA (1x2)
9k
9k
—
—
9k
12k
—
—
9k
18k
—
—
12k
12k
—
—
12k
18k
—
—
18k
18k
—
—
QUA (1x3)
9k
9k
9k
—
9k
9k
12k
—
9k
9k
18k
—
9k
12k
12k
—
12k
12k
12k
—
QUA(1x4)
9k
9k
9k
9k

11
Heat Controller, Inc. VMH SerieS Service Manual
10
7. Installation Details
7.1 Wrench torque sheet for installation
Outside diameter Torque Additional tightening torque
mm inch
N
.
m
N
.
m
Ф6.35 1/4 15(153kgf.cm) 16(163kgf.cm)
Ф9.52 3/8 25(255kgf.cm) 26(265kgf.cm)
Ф12.7 1/2 35(357kgf.cm) 36(367kgf.cm)
7.2 Connecting the cables
 The power wiring should always follow NEC and local codes, with respect to the unit’s, rating plate. See
installation manual for additional information. Main power connection is 208/230V/1PH~60HZ.
 The communicating cable, which connects between the indoor and outdoor units must meet all NEC and
local codes, with respect to the unit’s rating plate. We recommend using 14 AWG/4 conductor Stranded THHN
6ФФV cable.
Pipe length and elevation
Unit
Pipe size Standard
length
(m)
Max.
Elevation
B (m)
Max.
Length
A (m)
Additional
refrigerant
(g/m)
Gas inch
(mm)
Liquid inch
(mm)
9K 3/8’’ (Ф9.52) 1/4’’ (Ф6.35) (5)
16.5ft
(10)
33ft
(15)
50ft
(20)
0.2 oz/ft
12K/18K 1/2’’ (Ф12.7) 1/4’’ (Ф6.35)
Max. Total length for all rooms
Dual-zone(m) Tri-zone(m) Quad-zone(m)
(30)100ft (45)150ft (60)200ft
NOTES:
 Capacity test is based on standard length and maximum allowance length is based on reliability.
 Oil trap should be installed per (3-5 meters)10-15ft.
 Outdoor connections are ¼” (Ф6.35 mm) liquid and 3/8” (Ф9.52 mm) gas, therefore a reducer is
provided with all 12/18k indoor sections.
2LOWUDS
,QGRRUXQLW
2XWGRRUXQLW
$
%

12
Service Manual VMH SerieS Heat Controller, Inc.
11
7.4 Installation for the first time
Air and moisture in the refrigerant system have undesirable effects as indicated below:
●Pressure in the system rises.
●Operating current rises.
●Cooling or heating efficiency drops.
●Moisture in the refrigerant circuit may freeze and block capillary tubing.
●Water may lead to corrosion of parts in the refrigerant system.
Therefore, the indoor units and the pipes between indoor and outdoor units must be leak tested and
evacuated to remove gas and moisture from the system.
Gas leak check (Soap water method):
Apply soap water or a liquid neutral detergent on the indoor unit connections and outdoor unit
connections with a soft brush to check for leakage on the connecting points of the piping. If air bubbles
come out, the connections have leaks and those connection points must be tightened. Recheck to
ensure all leakage points are tightened properly and not leaking.
1. Air purging with vacuum pump
1) Completely tighten the flare nuts of the indoor and outdoor units, confirm that both the 2-way and
3-way valves are set to the closed position.
2) Connect the charge hose with the push pin of handle lo to the 3-way valves gas service port..
3) Connect the charge hose of handle hi connection to the vacuum pump.
4) Fully open the handle Lo of the manifold valve.
5) Operate the vacuum pump to evacuate.
6) Conduct evacuation for 30 minutes and check whether the compound meter indicates -0.1Mpa. If
the meter does not indicate -0.1Mpa after pumping 30 minutes, it should be pumped 20 minutes more. If
(Indoor unit)
(Liquid side)
(Gas side)
Vacuum
pump
Vacuum
pump
Lo Hi
Handle Hi
Two-way valve
Close
Manifold valve
Compound meter
Pressure
gauge
-0.1MPa
Handle Lo
Charge hose
Charge hose
(Outdoor unit)
Close
Three-way valve

13
Heat Controller, Inc. VMH SerieS Service Manual
12
the pressure can’t achieve -0.1Mpa after pumping 50 minutes, please check if there are some leakage
points. Once the meter indicates -0.1mpa, fully close the handle Lo valve of the manifold valve and stop
the operation of the vacuum pump. Confirm that the gauge needle does not move (approximately 5
minutes after turning off the vacuum pump).
7) Turn the flare nut of the 3-way valves about 45° counterclockwise for 6 or 7seconds after the gas
comes out, then tighten the flare nut again. Make sure the pressure display in the pressure indicator is a
little higher than the atmospheric pressure. Then remove the charge hose from the 3 way valve.
8) Fully open the 2 way valve and 3 way valve and securely tighten the cap of the 3 way valve.
2. Air purging by refrigerant
Procedure:
1). Confirm that both the 2-way and 3-way valves are set to the closed position.
2). Connect the charge set and a charging cylinder to the service port of the 3-way valve.
3). Air purge by open the valves on the charging cylinder and the charge set. Purge the air by loosening
the flare nut on the 2-way valve approximately 45° for 3 seconds then closing it for 1 minute; repeat 3
times. After purging the air, use a torque wrench to tighten the flare nut on the 2-way valve.
4). Check for gas leakage by checking the flare connections using the soap water method.
5). Discharge the refrigerant by closing the valve on the charging cylinder and discharging the refrigerant
by loosening the flare nut on the 2-way valve approximately 45° until the gauge indicates 0.3 to 0.5 Mpa.
6). Disconnect the charge set and the charging cylinder, and set the 2-way and 3-way valves to the open
position.
Be sure to use a hexagonal wrench to operate the valve stems.

14
Service Manual VMH SerieS Heat Controller, Inc.
13
7). Replace the valve stems nuts and the service port cap that were previously removed.
Be sure to use a torque wrench to tighten the service port cap to a torque of 18N·m.
Be sure to check for gas leakage using soap water.
3. Adding the refrigerant if the pipe length >(5m)16.5ft
Procedure:
1). Connect the charge hose to the charging cylinder, open the 2-way valve and the 3-way valve.
Connect the charge hose which you disconnected from the vacuum pump to the valve at the bottom of
the cylinder. Because refrigerant is R410A, turn the cylinder upside down, ensuring the bottom is upward,
to create a liquid charge.
2). Purge the air from the charge hose.
Open the valve at the bottom of the cylinder and press the check valve on the charge set to purge the air
(be careful of the liquid refrigerant).
3) Put the charging cylinder onto the electronic scale and record the weight.
4) Operate the air conditioner in the cooling mode.
5) Open the valves (Low side) on the charge set and charge the system with the proper amount (refer to
table) liquid refrigerant.
Electronic scale

15
Heat Controller, Inc. VMH SerieS Service Manual
14
6).When the electronic scale displays the proper weight (refer to the table), disconnect the charge hose
from the 3-way valve’s service port immediately and turn off the air conditioner before disconnecting the
hose.
7). Replace the valve stem caps and the service port that were previously removed.
Use torque wrench to tighten the service port cap to a torque of 18N.m.
Be sure to check for gas leakage using soap water.
7.5 Adding the refrigerant due to loss of charge
Procedure:
1). Connect the charge hose to the 3-way service port, open the 2-way valve and the 3-way valve.
Connect the charge hose to the valve at the bottom of the cylinder. Because the refrigerant is R-410A,
turn the cylinder upside down, such that the bottom is upward, to ensure a liquid charge.
2). Purge the air from the charge hose.
Open the valve at the bottom of the cylinder and press the check valve on the charge set to purge the air
(Do not vent refrigerant into the atmosphere).
3) Put the charging cylinder onto the electronic scale and record the weight.
4) Operate the air conditioner in the cooling mode.
5) Open the valves (Low side) on the charge set and charge the system with liquid refrigerant, (refer to
the gauge and the pressure of the low side).
6).When the electronic scale displays the proper weight (refer to the gauge and the pressure of the low
Electronic scale

16
Service Manual VMH SerieS Heat Controller, Inc.
15
side), disconnect the charge hose from the 3-way valve’s service port immediately and turn off the air
conditioner before disconnecting the hose.
7). Replace the valve stem caps and the service port that were previously removed.
Use torque wrench to tighten the service port cap to a torque of 18N.m.
Be sure to check for gas leakage using soap water.
7.6 Replacing the indoor unit
1. Collecting the refrigerant into the outdoor unit
Procedure
1). Confirm that both the 2-way and 3-way valves are set to the open position
Remove the valve stem caps and confirm that the valve stems are in the open position.
Be sure to use a hexagonal wrench to operate the valve stems.
2). Connect the charge hose with the push pin of handle lo to the 3-way valves gas service port.
3). Air purging of the charge hose.
Open the handle Lo valve of the manifold valve slightly to purge air from the charge hose for 5 seconds
and then close it quickly.
4). Set the 2-way valve to the closed position.
5). Operate the air conditioner in the cooling cycle and stop it when the gauge indicates 0.1MPa.
6). Set the 3-way valve to the closed position immediately

17
Heat Controller, Inc. VMH SerieS Service Manual
16
Do this quickly so that the gauge ends up indicating 0.3 to 0.5Mpa.
Disconnect the charge set, and tighten the 2-way and 3-way valve’s stem nuts.
Use a torque wrench to tighten the 3-way valves service port cap to a torque of 1.8 N.m.
Be sure to check for gas leakage using soap water.
7). Remove the defective indoor unit and install the new indoor unit. Follow the next set of procedures to
charge.
2. Air purging by the refrigerant
Procedure:
1). Confirm that both the 2-way and 3-way valves are set to the closed position.
2). Connect the charge set and a charging cylinder to the service port of the 3-way valve
Leave the valve on the charging cylinder closed.
3). Air purging.
Open the valves on the charging cylinder and the charge set. Purge the air by loosening the flare nut on
the 2-way valve approximately 45° for 3 seconds then closing it for 1 minute; repeat 3 times.
After purging the air, use a torque wrench to tighten the flare nut on the 2-way valve.
4). Check the gas leakage
Check the flare connections for gas leakage using soap water.
5). Discharge the refrigerant into charging cylinder.
Close the valve on the charging cylinder and discharge the refrigerant by loosening the flare nut on the

18
Service Manual VMH SerieS Heat Controller, Inc.
17
2-way valve approximately 45° until the gauge indicates 0.3 to 0.5 Mpa.
6). Disconnect the charge set and the charging cylinder, and set the 2-way and 3-way valves to the open
position
Be sure to use a hexagonal wrench to operate the valve stems.
7). Replace the valve stems nuts and the service port cap that were previously removed.
Be sure to use a torque wrench to tighten the service port cap to a torque 18N.m.
Be sure to check the gas leakage using soap water.
7.7 Replacing the outdoor unit
1. Evacuation for the whole system
Procedure:
1). Confirm that both the 2-way and 3-way valves are set to the open position.
2). Connect the vacuum pump to 3-way valve’s service port.
3). Evacuate for approximately one hour. Confirm that the compound meter indicates -0.1Mpa.
4). Close the valve (Low side) on the charge set, turn off the vacuum pump, and confirm that the gauge
needle does not move (approximately 5 minutes after turning off the vacuum pump).
5). Disconnect the charge hose from the vacuum pump.
6). Remove the defective outdoor unit and install the new unit. See the following instructions for
re-charging the new unit.

19
Heat Controller, Inc. VMH SerieS Service Manual
18
2. Refrigerant charging
Procedure:
1). Connect the charge hose to the charging cylinder, open the 2-way valve and the 3-way valve
Connect the charge hose which you disconnected from the vacuum pump to the valve at the bottom of
the cylinder. Because the refrigerant is R-410A, turn the cylinder upside down, such that the bottom is
upward, to ensure a liquid charge.
2). Purge the air from the charge hose
Open the valve at the bottom of the cylinder and press the check valve on the charge set to purge the air
(Do not vent refrigerant into the atmosphere).
3) Put the charging cylinder onto the electronic scale and record the weight.
4). Open the valves (Low side) on the charge set and charge the system with liquid refrigerant
If the system cannot be charge with the specified amount of refrigerant, or can be charged with a little at
a time (approximately (150g),5oz. each time) , operating the air conditioner in the cooling cycle. Wait
approximately 1 minute and then repeat the procedure as needed.
5).When the electronic scale displays the proper weight, disconnect the charge hose from the 3-way
valve’s service port immediately
If the system has been charged with liquid refrigerant while operating the air conditioner, turn off the air
conditioner before disconnecting the hose.
6). Replace the valve stem caps and the service port that were previously removed.
Use torque wrench to tighten the service port cap to a torque of 18N.m.
Be sure to check for gas leakage using soap water.

20
Service Manual VMH SerieS Heat Controller, Inc.
8. Electronic control function
8.1 Abbreviations
T1: Indoor ambient temperature
T2: Coil temperature of indoor heat exchanger middle.
T2B: Coil temperature of indoor heat exchanger outlet.
T3: Coil temperature of outdoor heat exchanger
T4: Outdoor ambient temperature
T5: Compressor discharge temperature
Ts: Set point temperature.
8.2 Electric control working environment.
8.2.1 Input voltage: 230V.
8.2.2 Input power frequency:60Hz.
8.2.3 Indoor fan normal working amperage. is less than 1A.
8.2.4 Outdoor fan normal working amperage. is less than 1.5A.
8.2.5 Four-way valve normal working amperage. is less than 1A.
8.2.6 Swing motor: 12V DC.
8.3 Outdoor unit’s digital display
There is a digital display tube in outdoor PCB.
Digital display functions:
•In standby , the LED displays “- -”
•When compressor is operating, the LED displays the running frequency,
•In defrosting mode, The LED displays “dF” or alternatively displays between running frequency and
“dF”(each displays 2s)
•In compressor pre-heating, The LED displays “- -”
•In protection or malfunction modes, the LED displays the associated error code or protection code.
8.4 Outdoor unit point check function
There is a check switch in outdoor PCB.
Push the switch SW1 to check the states of unit when the unit is running. The digital display will display the
following each time the SW1 switch is preserved.
No.SW1
Pressed
Display
Remark
1 Indoor unit capacity demand code
2 Outdoor unit running mode code Off:0, Cooling:1, Heating:2
3
Amendatory capacity demand code
4 Outdoor unit fan motor state Off:0, Low speed:1, High speed:2
5
Evaporator outlet temp. for 1# indoor unit
Actual data is measured, however due to display limitations
if the temp. is lower than -9 degrees, the digital display will
show “-9”. If the temp. is higher than 70 degrees, the digital
display will show “70”. If the indoor unit is not connected, the
digital display tube will show: “- -“.
6 Evaporator outlet temp. for 2# indoor unit
7 Evaporator outlet temp. for 3# indoor unit
8 Evaporator outlet temp. for 4# indoor unit
9
Condenser pipe temp.
10 Ambient temp.
11 Compressor discharge temp. Actual data is measured, however due to display limitations
if the temp. is lower than 0 degrees, the digital display will
show “0”. If the temp. is higher than 99 degrees, the digital
display will show single digit and a tens digit. For example if
the digital display shows “0.5”, it means the compressor