SERVICE MANUAL Inverter Single Zone Ductless Mini Split Heat Pump VMH Series Version C VMH09SC-1 VMH12SC-1 VMH18SC-1 VMH24SC-1 Heat Controller, Inc. • 1900 Wellworth Ave. • Jackson, MI 49203 • (517)787-2100 • www.heatcontroller.
Service Manual VMH Series Heat Controller, Inc. CONTENTS 1.Safety Precautions.............................................................................................................................. 3 2. Functions............................................................................................................................................ 8 3. Dimensions.......................................................................................................................................
Heat Controller, Inc. VMH Series Service Manual 1. Precaution 1.1 Safety Precaution To prevent injury to the user or other people and property damage, the following instructions must be followed. Incorrect operation due to ignoring instruction will cause harm or damage. Before service unit, be sure to read this service manual at first. 1.2 Warning Installation Do not use a defective or underrated circuit breaker. Use this appliance on a dedicated circuit.
VMH Series Service Manual Heat Controller, Inc. Sharp edges could cause injury, be especially careful of the case edges and the fins on the condenser and evaporator. For installation, always contact the dealer. There is risk of fire, electric shock, explosion, or injury. Do not install the product on a defective installation stand. It may cause injury, accident, or damage to the product. Be sure the installation area does not deteriorate with age.
Heat Controller, Inc. VMH Series Service Manual Do not use the telephone or turn switches on or off. There is risk of explosion or fire. If strange sounds, or small or smoke comes from product. Turn the breaker off or disconnect the power supply cable. There is risk of electric shock or fire. Stop operation and close the window in storm or hurricane. If possible, remove the product from the window before the hurricane arrives.
VMH Series Service Manual Heat Controller, Inc. Keep level even when installing the product. To avoid vibration of water leakage. Use two or more people to lift and transport the product. Avoid personal injury. Do not install the product where it will be exposed to sea wind (salt spray) directly. It may cause corrosion on the product. Corrosion, particularly on the condenser and evaporator fins, could cause product malfunction or inefficient operation.
Heat Controller, Inc. VMH Series Service Manual A dirty filter reduces the efficiency of the air conditioner and could cause product malfunction or damage. Do not insert hands or other object through air inlet or outlet while the product is operated. There are sharp and moving parts that could cause personal injury. Do not drink the water drained from the product. It is not sanitary could cause serious health issues. Use a firm stool or ladder when cleaning or maintaining the product.
VMH Series Service Manual Heat Controller, Inc. 2. Function Indoor unit Operation by remote controller Sensing room temperature Room temperature sensor Pipe temperature sensor Room temperature control Maintains the room temperature according to the set temperature Indoor golden fin Anti-freeze protection in cooling Prevents condensate from freezing on evaporator by sensing the evaporator pipe temperature in cooling mode Ionizer Indoor golden fin Time Delay Safety control Restart is for approx.
VMH Series Heat Controller, Inc. Outdoor unit Compressor delay 3 minute time delay between ON/OFF operation. Low noise air flow system Bird tail propeller fan makes the outdoor unit run more quietly. Hydrophilic aluminum fin 4 way valve control Energized in the heating mode except when in defrost. Anti-rust cabinet Made from electrolytic zinc steel and anti-rust coated components. Valve protection cover Protects the valves and prevents water from dripping.
VMH Series Service Manual Heat Controller, Inc. 3. Dimension 3.1 Indoor Unit Dimension (mm) Model W H D B-VMH09SC 845 286 165 B-VMH12SC (33.3in) (11.3in) (6.5in) B-VMH18SC 1080 320 200 B-VMH24SC (42.5in) (12.6in) (7.
VMH Series Heat Controller, Inc. Service Manual 3.2 Outdoor Unit Model Dimension (mm) W D H W1 A B 760 (29.9in) 285 (11.2in) 590 (23.2in) 823 (32.4in) 530 (20.9in) 290 (11.4in) A-VMH18SC 845 (33.3in) 335 (13.2in) 695 (27.4in) 918 (36.1in) 560 (22.0in) 335 (13.2in) A-VMH24SC 895 (35.2in) 330 (13.0in) 860 (33.9in) 975 (38.4in) 590 (23.2in) 333 (13.
VMH Series Service Manual Heat Controller, Inc. 4.
VMH Series Heat Controller, Inc. Service Manual 5. Wiring Diagrams: 5.
VMH Series Service Manual Heat Controller, Inc. 5.
VMH Series Heat Controller, Inc. Service Manual A-VMH24SC-1 6. Installation details: 6.1 Power Wiring • Consult local building codes, NEC (National Electrical Code) or CEC (Canadian Electrical Code) for special requirements. Connection Cable: Voltage drop on the connecting cable should be kept to a minimum. The operating voltage will vary between – 24V to +24V DC.
VMH Series Service Manual Heat Controller, Inc. 6.2 Pipe length and the elevation: 1. Single Zone “V” Series Inverter System: Capacity Btu/h Pipe Size Standard Length A Max Total Elevation B Additional Gas Liquid Line Length (ft) A Refrigerant (in) (in) (ft) (ft) Min. Max. oz/ft 9k 3/8 1/4 *16.5 26 10 65.5 .2 12k 1/2 1/4 *16.5 26 10 65.5 .2 18k 1/2 1/4 *16.5 32 10 82 .2 24k 5/8 3/8 *16.5 32 10 82 .
VMH Series Heat Controller, Inc. Service Manual 6.3 Pressure Test & Evacuation Air and moisture in the refrigerant system have undesirable effects as 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. Refrigerant lines and indoor coil should be evacuated using the recommended deep vacuum method of 500 microns.
VMH Series Service Manual Heat Controller, Inc. 2. Deep Vacuum Method The deep vacuum method requires a vacuum pump capable of pulling a vacuum of 500 microns and a vacuum of 500 microns and vacuum gage capable of accurately measuring the vacuum depth. The deep vacuum method is the most positive way of assuring a system is free of air and liquid water. 1. 2. 3. 4. Vacuum pressure should pull down below 500 microns in 2 minutes. Evacuate system for 30 minutes. Shut valve to vacuum pump off.
VMH Series Heat Controller, Inc. Service Manual 8. Electronic function 8.1 Abbreviation T1: Indoor room temperature T2: T3: T4: T5: TS: Coil temperature of evaporator Coil temperature of condenser Outdoor ambient temperature Compressor discharge temperature Preset temperature. 8.2 Display function 8.2.1 Icon explanation on indoor display board. TIMER display Illuminated during Timer operation. CLEAN AIR display(optional) Illuminated when Ionizer is activated.
Service Manual VMH Series Heat Controller, Inc. 8.3 Main Protection 8.3.1 Three Minute Time Delay at restart for compressor. 1 minute delay for 1st time start-up and 3 minute delay for others. 8.3.2 Temperature protection of compressor top. Protector cuts off compressor for 30 seconds and restarts after 3 minute delay. 8.3.3 Temperature protection of compressor discharge.
VMH Series Heat Controller, Inc. Service Manual Preheat mode: • With the compressor off, a small amount of current flows through the windings of the compressor heating the crankcase. Preheat termination: • If T4＞41°F/5°C or user turns on the machine and compressor runs, preheating function will stop. • Crankcase heater starts when T4<41°F/5°C and stops when T4>59°F/15°C. 8.4 Operation Modes and Functions 8.4.1 Fan only mode. (1) Outdoor fan and compressor stop.
VMH Series Service Manual Heat Controller, Inc. 8.4.2 Cooling Mode 8.4.2.1 Compressor running rules: The operating frequency of compressor after starting submits to following rule. T4 °F 113 °C (45) 109 (43) 104 (40) 100 (38) 86 (30) 82 (28) 72 (22) 68 (20) If users switch on A/C by remote controller, the compressor will run at the Fmax frequency for 7 minutes according to outdoor ambient temp. During the 7 minutes, frequency limitation is active.
VMH Series Heat Controller, Inc. Service Manual Note: When T1-Ts stays in the same temp. zone for 3 minutes, the compressor will run as follows: A~E: Increases the frequency to level F8. F: Maintains the current frequency. G: Decreases the frequency to the lower level F1. H: Runs at F1 for 1h.(if T1-Ts<28°F/-2°C, compressor will stop) Meanwhile, the compressor running frequency is limited by the current.
VMH Series Service Manual Heat Controller, Inc. 8.4.2.2 Outdoor fan rules: Outdoor fan and compressor start at the same time, outdoor fan stops 30s after the compressor stops. The outdoor fan has two speeds, and is controlled by T4 as follows: T4 °F °C 72 (22) 68 (20) 8.4.2.3 Indoor fan running rules In cooling mode, indoor fan runs all the time and the speed can be selected as high, medium, low and auto. Auto fan in cooling mode acts as follow: T1-Ts °F 7° 5° 3° 2° °C (4.0) (3.0) (1.5) (1.0) 8.
VMH Series Heat Controller, Inc. Service Manual 8.4.2.5 Evaporator low temperature T2 protection. When T2<32°F/0°C, the compressor will stop and restart when T2>41°F/5°C. When 32°F/0°C≤T2<39°F/4°C, the compressor frequency is limited and decreases to the lower level every minute until stop the compressor stops. When 39°F/4°C ≤T2≤45°F/7°C, the compressor will keep the current frequency. When T2>45°F/7°C, the compressor frequency will not be limited. 8.4.3 Heating Mode 8.4.3.
VMH Series Service Manual Heat Controller, Inc. After A/C starts up, the compressor will run at the Fmax frequency for 7 minutes according to outdoor ambient temp. During the 7 minutes, frequency limitation is active. 7 minutes later, compressor running frequency will be controlled as below: T1-Ts-ΔT °F °C 41 (+5.0) 40 (+4.5) 38 (+3.5) 37 (+3.0) 37 (+2.5) 36 (+2.0) 35 (+1.5) 34 (+1.0) 33 (+0.5) While Temp.
VMH Series Heat Controller, Inc. Service Manual Meanwhile, the compressor running frequency is limited by the current. Frequency decreases Frequency holds If the current increases more than I2HEAT, the frequency will decrease automatically, if the current raises to over I3HEAT,, the compressor will stop and restart 3min later. During the frequency decreasing, if the current deceases to between I1HEAT, and I3HEAT,, the frequency will hold.
VMH Series Service Manual Heat Controller, Inc. 8.4.3.3 Indoor fan rules: The indoor fan speed can be selected as high, medium, low and auto, the anti-cold-wind function has the priority. If set temperature is reached, the indoor fan switches to lowest speed, the anti-cold wind function has priority. If operation mode is changed or compressor restarts, indoor fan works in set fan speed.
VMH Series Heat Controller, Inc. Service Manual Auto fan action in heating mode. T1-Ts-ΔT °F °C 5° 4° 3° 2° (2.5) (2.0) (1.5) (1.0) 8.4.3.4 Defrost mode： Conditions of defrost: When the unit is running, if any one of the following conditions is satisfied, the unit starts defrost: 1 .Defrost is available after 40 minutes of run time if T3 (Condenser coil temperature) is＜37°F/3°C and there is a 11°F/6°C temperature difference for 3 minutes. 2.
Service Manual VMH Series Defrost Actions: For 9K and 12K unit For 18K and 24K unit 30 29 Heat Controller, Inc.
VMH Series Heat Controller, Inc. Service Manual 8.4.3.5 High evaporator coil temp.T2 protection: (1) T2>TEH2 compressor running frequency decreases to the lower level every 20s. If the frequency decreased to F2 and the T2 still over TEH2 for 3 minutes, the compressor will stop. If T2 deceased to lower than 118°F/48°C, or 118°F/48°C
VMH Series Service Manual Heat Controller, Inc. 8.4.5 Dehumidify mode 8.4.5.1 Indoor fan speed is fixed in breeze and can’t be changed. The louver angle is the same as in cooling mode. 8.4.5.2 Compressor running rules T1-Ts °F °C 36.5 (2.5) 35.6 (2.0) 34.7 (1.5) 33.8 (1.0) 32.9 (0.5) 32 (0.0) 8.4.5.3 Room low temperature protection If room temperature is lower than 50°F/10°C, compressor will stop and not resume operation until room temperature is over 54°F/12°C. 8.4.5.
Heat Controller, Inc. VMH Series Service Manual 8.4.6.2 In forced operation mode, all general protections and remote control functions are available. 8.4.6.3 Operation rules: Forced cooling mode: The compressor runs at F2 frequency and indoor fan runs as breeze. After running for 30 minutes. the machine will turn to auto mode at 75°F/24°C set temperature. Forced auto mode: The action of forced auto mode is the same as normal auto mode with 75°F/24°C set temperature. 8.4.7 Timer function 8.4.7.
Service Manual VMH Series Heat Controller, Inc. 8.4.8.3 Timer setting is available 8.4.8.4 When user uses timer off function in sleep mode (or sleep function in timer off mode), if the timing is less than 7 hours, sleep function will be cancelled when the set time reached. If the timing is more than 7 hours, the machine will not stop until it reaches the set time in sleep mode. 8.4.
VMH Series Heat Controller, Inc. Service Manual 8.4.11.2 After the A/C is turned on, the Clean Air function is switched on when the A/C receives FRESH CODE the first time, and ionizer is switched off when the A/C receives the CODE again. 8.4.11.3 After starting the Clean Air function, the ionizer will work only when the indoor fan motor is running. If the indoor fan motor is off, the ionizer also stops working, even though the Clean Air function is available. 8.4.11.
VMH Series Service Manual Heat Controller, Inc. 9. Troubleshooting 9.
VMH Series Heat Controller, Inc. Service Manual E1: 9.2.2 Indoor unit and outdoor unit communication protection error diagnosis and solution Turn off the power supply, after 1 minute, reapply the power, turn on the unit with remote controller Does E1 code clear Check the wiring between indoor and outdoor unit.
VMH Series Service Manual Heat Controller, Inc. E2: 9.2.3 Zero crossing check resistance or inverter compressor, it is .7Ω error Alarm signal when the main chip can’t detect over-zero signal. When such failure occurs, the main control board must have fault. Turn off the power supply for 5 seconds, then turn it back on. No Check power supply and connections Correct power supply or correct connections Yes Indoor PCB defective E3: INDOOR OR E7 OUTDOOR 9.2.
VMH Series Heat Controller, Inc. Service Manual E5 & E6 9.2.5 Open or short circuit of temperature sensor diagnosis and solution Check the connections between the sensors and the PCB. Are the connections good? Yes Yes Replace the sensor and check if E5 or E6 displays again? Replace the outdoor or Replace the outdoor or indoor PCB indoor PCB P0: 9.2.
VMH Series Service Manual Heat Controller, Inc. P1: 9.2.7 Over voltage or too low voltage protection diagnosis and solution No Is the power supply good? Make sure the power supply is normal. Yes Replace the outdoor e-box. P2: 9.2.
VMH Series Heat Controller, Inc. Service Manual 9.29 P3 ERROR – Low Ambient Protection If the outdoor temperature remains at 5°F(-15°C) for an hour, the compressor will turn off and the error code “P3” will be displayed on the indoor unit. Once the compressor has been off for at least an hour and the temperature outside is equal to or greater than 10.4°F(-12°C) for at least ten minutes, the system will restart.
Service Manual VMH Series Heat Controller, Inc. Key parts checking. 8.3.1. Compressor checking (Model: DA108X1C-20FZ3) Measure the resistance value of each winding by using the multi-meter. Position Resistance Value Blue - Red Blue - Black 0.71Ω (20℃) Red - Blue Step Motor (Model: MP2835T) Measure the resistance value of each winding by using the multi-meter. Position Black - Red Red -Yellow 41 42 Resistance Value 56.5Ω (20℃) 117.
Heat Controller, Inc. VMH Series Service Manual 8.3.1. Compressor checking (Model: DA150S1C-20FZ) Measure the resistance value of each winding by using the multi-meter. Position Resistance Value Blue - Red Blue - Black 0.95Ω (20℃) Red - Blue Outdoor Fan Motor (Model: YDK53-6FB) Measure the resistance value of each winding by using the multi-meter.
VMH Series Service Manual Heat Controller, Inc. Temperature Sensors. Room temp.(T1) sensor, Indoor coil temp.(T2) sensor, Outdoor coil temp.(T3) sensor, Outdoor ambient temp.(T4) sensor, Compressor exhaust temp.(Te) sensor. Measure the resistance value of each winding by using the multi-meter. Some frequently-used R-T data for Te sensor: Temperature (0°F) Resistance Value (KΩ) 41°F/5°C 59°F/15°C 77°F/25°C 95°F/35°C 140°F/60°C 158°F/70°C 176°F/80°C 194°F/90°C 212°F/100°C 141.6 88 56.1 36.
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