Heat Pump - Carrier 38YY...G Installation Manual

38YY...G / 38YYS...G
Unit maintenance, troubleshooting and guide for the owner
Unit maintenance
The following maintenance operations must be carried out by
qualified personnel.
Cleaning the coil
When necessary, proceed as follows for more careful cleaning of
the coil:
Switch the mains supply OFF.
Remove unit top cover by loosening holding screws and lifting
the cover.
Carefully clean the coil with a vacuum cleaner from inside to outside.
With the same vacuum cleaner, dust the inside of the fan
compartment and the fan blades. Avoid any damage to the blades
which may cause future vibrations and noise.
Replace the unit cover and tighten the screws.
After long shutdown periods and at commissioning
(for heat pump models only)
Energize the system by putting the main switch to ON without
starting the unit. (Remote control must be in the OFF position).
Do not disconnect the main switch during the unit operating season.
Troubleshooting
Compressor and fan of the outdoor unit will not start:
• Unit not energized; check the mains power connections.
• Main switch OFF; check and put to the ON position.
• Main switch fuses have blown; replace.
• Wait for 3 minutes; compressor cycling protection is on.
• Pressure switch open; check and eliminate cause.
• Mains voltage too low.
• Electrical connections loose or wrong; check and repair.
Compressor will not start, but outdoor fan is running:
• Electrical connections of compressor loose or wrong; check and repair.
• Compressor burnt out, seized or protection device on; check for
the cause and replace compressor if necessary.
• Run capacitor faulty (single-phase models); replace.
Compressor starts, but stops due to its overtemperature
protection (other than stops caused by the normal operation
of the thermostat):
• Wrong refrigerant charge (excessive or low) or air or other non
condensable gases in the circuit; drain refrigerant (see note 1),
evacuate and recharge.
• Mains voltage wrong (too high or too low).
• Condenser coil (outdoor or indoor, in case of heat pump
operation) obstructed; remove obstructions.
• Outdoor fan off; check cause and repair.
• Run capacitor faulty; check and replace.
• Refrigerant circuit clogged; check and remove obstructions.
• Reversing valve faulty on heat pump models; replace.
• Expansion device clogged or covered with ice; drain refrigerant
(see note 1), evacuate and recharge.
GB - 12
R-410A
Compressor runs continuously:
• Unit selected too small for actual air conditioning needs.
• Indoor temperature selection too low (if in cooling) or too high (if in
heating, for heat pump models); check temperature selection.
• Refrigerant charge low; check and add refrigerant.
• Condenser fan (outdoor or indoor, in case of heat pump operation)
faulty; replace.
• Air or other non condensable gases in the circuit; drain refrigerant
(see note 1), evacuate and recharge.
• Obstructions at air intake or dirty indoor unit filters; remove
obstruction or clean filter.
Frequent ice build-up on outdoor coil (during heating with
heat pump units):
• Outdoor fan stopped; check cause and repair.
• Wrong electrical connections between indoor and outdoor units;
check electrical connections and repair.
• Check defrost end thermostat positioning and connection.
Discharge pressure too high:
• Outdoor coil dirty or obstructed; clean or remove obstructions.
• Condenser fan (outdoor or indoor, in case of heat pump operation)
faulty; replace.
• Refrigerant charge too high; drain some refrigerant (see note 1).
• Air or other non-condensable gases in the circuit; drain refrigerant
(see note 1), evacuate and recharge.
Discharge pressure too low:
• Refrigerant charge too low; add refrigerant.
• Outdoor coil dirty or obstructed; clean or remove obstructions.
• Indoor unit air filter dirty; clean filter.
Suction pressure too high:
• Refrigerant charge too high; drain some refrigerant (see note 1).
• Reversing valve faulty or internal leak; replace.
Suction pressure too low:
• Refrigerant charge too low; add refrigerant.
• Evaporator coil (indoor or outdoor, in case of heat pump
models),covered with ice; see the following points.
• Air circulation on the evaporator unit (indoor or outdoor, in case of
heat pump models) not sufficient; check for the cause and repair.
• Expansion device or suction line clogged: check and repair.
• Outdoor fan does not stop during defrost periods (when heating
with heat pump models); check electrical connections.
Outdoor fan cycling due to its overtemperature protection:
• Fan capacitor faulty; replace.
• Electrical connection loose; check connections.
• Fan bearing seized; check and repair.
Outdoor fan motor running always at low speed:
• Wiring not connected to the board; check connections between
temperature sensor and board.
• Temperature sensor is fault; replace the sensor.
• Electronic board broken; replace board.
Outdoor fan motor running always at high speed:
• Temperature sensor is short circuited; replace temperature
sensor.
• Electronic board broken; replace board.
Note 1: Do not release refrigerant to the atmosphere;
Guide for the owner
When installation and tests are completed explain the Operation
and Maintenance Manual to the owner, with particular attention to
the main operating modes of the air conditioner, such as:
• Turning the unit on and off.
• Functions of the remote control.
• Removal and cleaning of the air filters.
Leave the two installation manuals for the indoor and outdoor units
with the owner for future use during maintenance operations or for
any other needs.
use refrigerant recovery equipment.