Bosch FHP ES Series, Руководство по установке и обслуживанию

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6720220330 Revised 05-12
16
ES SERIES
TROUBLE SHOOTING
PROBLEM POSSIBLE CAUSE CHECKS AND CORRECTIONS
ENTIRE UNIT DOES
NOT RUN
Power supply off Apply power, close disconnect
Blown fuse Replace fuse or reset circuit breaker. Check for correct fuses.
Voltage supply low If voltage is below minimum voltage specified on unit data plate, contact local power company.
Thermostat
Set the fan to "ON", the fan should run. Set thermostat to "COOL" and lowest temperature setting,
the unit should run in the cooling mode (reversing valve energized). Set unit to "HEAT" and the
highest temperature setting, the unit should run in the heating mode. If neither the blower or
compressor run in all three cases, the thermostat could be miswired or faulty.To ensure miswired
or faulty thermostat verify 24 volts is available on the condensing section low voltage terminal
strip between "R" and "C", "Y" and "C", and "O" and "C". If the blower does not operate, verify 24
volts between terminals "G" and "C" in the air handler. Replace the thermostat if defective.
BLOWER OPERATES
BUT COMPRESSOR
DOES NOT
Thermostat Check setting, calibration, and wiring.
Wiring Check for loose or broken wires at compressor, capacitor, or contactor.
Safety controls Check UPM board red default L.E.D. for Blink Code
Compressor overload open If the compressor is cool and the overload will not reset, replace compressor.
Compressor motor grounded Internal winding grounded to the compressor shell. Replace compressor. If compressor burnout,
install suction filter dryer.
Compressor windings open After compressor has cooled, check continuity of the compressor windings. If the windings are
open, replace the compressor.
UNIT OFF ON
HIGH PRESSURE
CONTROL
Discharge pressure too high
In "COOLING" mode: Lack of or inadequate water flow. Entering water temperature too warm.
Scaled or plugged condenser.
In "HEATING" mode: Lack of or inadequate air flow. Blower inoperative, clogged filter or
restrictions in ductwork.
Refrigerant charge The unit is overcharged with refrigerant. Reclaim refrigerant, evacuate and recharge with factory
recommended charge.
High pressure Check for defective or improperly calibrated high pressure switch.
UNIT OFF ON
LOW PRESSURE
CONTROL
Suction pressure too low In "COOLING" mode: Lack of or inadequate air flow. Entering air temperature too cold. Blower
inoperative, clogged filter, or restrictions in ductwork.
In "HEATING" mode: Lack of or inadequate water flow. Entering water temperature too cold.
Scaled or plugged condenser.
Refrigerant charge The unit is low on refrigerant. Check for refrigerant leak, repair, evacuate and recharge with
factory recommended charge.
Low pressure switch Check for defective or improperly calibrated low pressure switch.
UNIT SHORT
CYCLES
Unit oversized Recalculate heating and or cooling loads.
Thermostat Thermostat installed near a supply air grill, relocate thermostat. Readjust heat anticipator.
Wiring and controls Loose connections in the wiring or a defective compressor contactor.
INSUFFICIENT
COOLING OR
HEATING
Unit undersized Recalculate heating and or cooling loads. If excessive, possibly adding insulation and shading will
rectify the problem.
Loss of conditioned air
by leaks Check for leaks in duct work or introduction of ambient air through doors or windows.
Airflow Lack of adequate air flow or improper distribution of air. Replace dirty filter.
Refrigerant charge Low on refrigerant charge causing inefficient operation.
Compressor
Check for defective compressor. If discharge is too low and suction pressure is too high,
compressor is not pumping properly. Replace compressor.
Reversing valve Defective reversing valve creating bypass of refrigerant from discharge to suction side of
compressor. Replace reversing valve.
Operating pressures Compare unit operating pressures to the pressure / temperature chart for the unit.
TXV Check TXV for possible restriction or defect. Replace if necessary.
Moisture, noncondensables The refrigerant system may be contaminated with moisture or noncondensables. Reclaim
refrigerant, evacuate and recharge with factory recommended charge. Note: a liquid line dryer
may be required.