Carrier heat pump troubleshooting

Carrier Air V heat pump troubleshooting

TROUBLEPOSSIBLE CAUSESSOLUTION
UNIT DOES NOT OPERATEThe unit may not be connected to the power supply correctly.Check the power supply of the vehicle and make sure it is provided correctly.
THE UNIT IS NOT COOLING OR HEATING THE ROOMThere could be blockage of unit's air output.Make sure that there are no obstacles restricting or blocking the unit's output.
The roof top air conditioner is not level.Mount the roof top air conditioner as level as possible from front to rear and side to side when the vehicle is parked. Make sure that the mounting of the air conditioner is correct and level.
The air filter is dirty.Remove and clean the filter.
THE UNIT IS NOT COOLING THE ROOMThe temperature setting is too high.Reset the Air V to a lower temperature setting.
The room was already very hot before the unit was turned on.Allow a sufficient amount of time for unit to cool the room.
THE UNIT IS NOT HEATING THE ROOMThe temperature setting is too low.Reset the Air V to a higher temperature setting.
The room was already very cold before the unit was turned on.Allow a sufficient amount of time for unit to heat the room.
THE UNIT IS MAKING NOISESThe unit is clicking and gurgling.These noises are normal during the operation of the unit.
THE UNIT HAS WATER DRIPPING INSIDEThe basepan gasket has not been evenly compressed to about 60%.Mounting bolts should be tightened evenly by compressing the basepan gasket to the sixty percent requirement.
THE UNIT HAS ICE OR FROST ON THE COILSThe filter is dirty.Remove and clean the filter.
THE UNIT ON LAMP FLICKERSThe malfunction of the sensors or compressor is detected.Contact the servicemen.

Carrier OMNIZONE 50BV020-064 heat pump troubleshooting

PROBLEMPOSSIBLE CAUSE
Control modules do not have lights when unit power is on.Transformer open. Circuit breaker open. Power wiring open. Module failure.
Control display does not light up when unit power is on.Connection location. Interface cable open. Display failure.
Run test will not start.Pre-existing ALARM (red)? Not “Logged in” with password. Switch not in local.
WARN (yellow) LED does not light during run test.Wiring open. Lamp failure. Control module failure.
ALARM (red) LED does not light during run test.Wiring open. Lamp open. Control module failure.
Run test stops, ALARM (red) LED light is lit after it blinks once.Bypass switch to LINE. Mode switch to OFF. Duct high pressure switch open. Fire shutdown input or jumper open.
Supply air temp out of range. Duct static pressure sensor out of range. Compressor resistor board wiring error or failure.
Fan does not start/ALARM (red) LED blinks 2 times.Fan relay failure.
Run test stop, ALARM (red) LED is lit after blinking 3 times.Wiring open. VFD connection error. VFD setup error. Fan relay failure. Current isolator failure. Control module failure.
Run test stop, ALARM (red) LED is lit after it blinks 4 times. Fan does not increase speed.VFD connection error. VFD setup error. Current isolator load adjustment too low.
Fan does not stop after ALARM (red) LED blinks 5 times.Fan relay failure.
Fan rotation is backwards.VFD to motor wiring sequence error. VFD setup error.
Run test stop, ALARM (red) LED is lit after blinking 6 times. Compressor 1 does not start.Wiring open. Compressor resistor board wiring error or failure. High pressure switch, low pressure switch, coil frost switch, or compressor protection module open. Compressor relay failure. Contactor failure. Control module failure. No refrigerant charge.
Run test stop, ALARM (red) LED is lit after blinking 7 times. Compressor 2 does not start.Wiring open. Compressor resistor board wiring error or failure. High pressure switch, low pressure switch, coil frost switch, or compressor protection module open. Compressor relay failure. Contactor failure. Control module failure. No refrigerant charge.
Run test stop, ALARM (red) LED is lit after blinking 8 times. Compressor 3 does not start.Wiring open. Compressor resistor board wiring error or failure. High pressure switch, low pressure switch, coil frost switch, or compressor protection module open. Compressor relay failure. Contactor failure. Control module failure. No refrigerant charge.
Run test stop, ALARM (red) LED is lit after blinking 9 times. Compressor 4 does not start.Wiring open. Compressor resistor board wiring error or failure. High pressure switch, low pressure switch, coil frost switch, or compressor protection module open. Compressor relay failure. Contactor failure. Control module failure. No refrigerant charge.
Compressor rotation is backwards.Field power wiring sequence error. Compressor power wiring sequence error.
“C" message in I/O status display.No input signal or communication failure.
“Service” message in I/O status display.Value is forced from 6400 keypad entry.
“Supervisor” message in I/O status display.Value is forced from network communication (i.e., PC).
ALARM (red) LED always on, will not enter run test.SAT, DSP, CSMUX, DHS, or PHASE input values. Mode switch OFF.

Carrier PERFORMANCE 50VT-A heat pump troubleshooting

SYMPTOMCAUSEREMEDY
Compressor and condenser fan will not start.Power failureCall power company
Fuse blown or circuit breaker trippedReplace fuse or reset circuit breaker
Defective contactor, transformer, or high-pressure, loss-of-charge or low-pressure switchReplace component
Insufficient line voltageDetermine cause and correct
Incorrect or faulty wiringCheck wiring diagram and rewire correctly
Thermostat setting too highLower thermostat setting below room temperature
Compressor will not start but condenser fan runsFaulty wiring or loose connections in compressor circuitCheck wiring and repair or replace
Compressor motor burned out. seized, or internal overload openDetermine cause Replace compressor
Defective run/start capacitor, overload, start relayDetermine cause and replace
One leg of 3-phase power deadReplace fuse or reset circuit breaker Determine cause
Three-phase scroll compressor makes excessive noise, and there may be a low pressure differential.Scroll compressor is rotating in the wrong directionCorrect the direction of rotation by rever 3-phase power leads to the unit.
Compressor cycles (other than normally satisfying thermostat).Refrigerant overcharge or underchargeRecover refrigerant, evacuate system, a charge to capacities shown on rating pla
Defective compressorReplace and determine cause
Insufficient line voltageDetermine cause and correct
Blocked condenserDetermine cause and correct
Defective run/start capacitor, overload or start relayDetermine cause and replace
Defective thermostatReplace thermostat
Faulty condenser-fan motor or capacitorReplace
Restriction in refrigerant systemLocate restriction and remove
Compressor operates continuouslyDirty air filterReplace filter
Unit undersized for loadDecrease load or increase unit size
Thermostat set too lowReset thermostat
Low refrigerant chargeLocate leak, repair, and recharge
Mechanical damage in compressorReplace compressor
Air in systemRecover refrigerant, evacuate system, and recharge
Condenser coil dirty or restrictedClean coil or remove restriction
Excessive head pressureDirty air filterReplace filter
Dirty condenser coilClean coil
Refrigerant overchargedRecover excess refrigerant
Air in systemRecover refrigerant, evacuate system, and recharge
Condenser air restricted or air short-cyclingDetermine cause and correct
Head pressure too lowLow refrigerant chargeCheck for leaks, repair, and recharge.
Compressor IPR leakingReplace compressor
Restriction in liquid tubeRemove restriction
Excessive suction pressureHigh heat loadCheck for source and eliminate
Compressor IPR leakingReplace compressor
Refrigerant overchargedRecover excess refrigerant
Suction pressure too lowDirty air filterReplace filter
Low refrigerant chargeCheck for leaks, repair and recharge
Metering device or low side restrictedRemove source of restriction
Insufficient evaporator airflowIncrease air quantity. Check filter-replace if necessary
Temperature too low in conditioned areaReset thermostat
Outdoor ambient below 55°P (12.7°C)Install low-ambient kit
Pilter drier restrictedReplace filter