Operating instructions

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XII. TROUBLESHOOTING GUIDE FOR UNIT OPERATION
PROBLEM POSSIBLE CAUSE CHECKS AND CORRECTIONS
Blown Fuse/Tripped Replace fuse or reset circuit breaker. (Check for correct size
Circuit Breaker fuse and circuit breaker.)
Blown Fuse on Controller Replace fuse on controller. (Check for correct size fuse.)
Broken or Loose Wires Replace or tighten the wires
Voltage Supply Low If voltage is below minimum voltage on data plate, contact local
power company.
Low Voltage Circuit Check 24 volt transformer for burnout or voltage less than 18
Entire unit does volts.
not run Thermostat Set thermostat on "Cool" and lowest temperature setting, unit
should run. Set thermostat on "Heat" and highest temperature
setting, unit should run. If unit does not run in both cases, the
thermostat could be wired incorrectly or be faulty. To prove
faulty or miswired thermostat, disconnect thermostat wires at the
unit and jumper between "R", "Y", and "G" terminals and unit
should run. Replace thermostat with correct heat pump thermostat only.
A substitute may not work properly.
Interruptible Power Check incoming supply voltage.
Thermostat Check setting, calibration, and wiring. If thermostat has an
anticipator, set it at 1.0 or 1.2.
Wiring Check for loose or broken wires at compressor, capacitor, or
contactor.
Blown Fuse Replace fuse or reset circuit breaker. (Check for correct size
fuse or circuit breaker.)
High or Low Pressure The unit could be off on the high or low pressure cutout control.
Controls Check water GPM, air CFM and filter, ambient temperature and
loss of refrigerant. If the unit still fails to run, check for faulty
pressure controls individually. Replace if defective.
Defective Capacitor Check capacitor. If defective; remove, replace, and rewire correctly.
Voltage Supply Low If voltage is below minimum voltage specified on the data plate,
Blower motor contact local power company. Check voltage at compressor for
runs but possible open terminal.
compressor Low Voltage Circuit Check 24 volt transformer for burnout or voltage less than 18
does not, or volts. With a voltmeter, check signal from thermostat at Y to X,
compressor M1 on controller to X, and the capacitor voltage drop. Replace
short cycles. component that does not energize.
Compressor Overload In all cases an "internal" compressor overload is used. If the
Open compressor motor is too hot, the overload will not reset until the
compressor cools down. If the compressor is cool and the
overload does not reset, there may be a defective or open
overload. Replace the compressor.
Compressor Motor Internal winding grounded to the compressor shell. Replace the
Grounded compressor. If compressor burnout occurs, install filter drier at
suction line.
Compressor Windings Check continuity or the compressor windings with an ohmmeter.
Open If the windings are open, replace the compressor.
Seized Compressor Try an auxiliary capacitor in parallel with the run capacitor
momentarily. If the compressor still does not start, replace it.
Thermostat The differential is set too close to the thermostat. Readjust heat
Unit Short anticipator to 1.0 or 1.2.
Cycles Thermostat Improperly located thermostat (e.g. near kitchen), inaccurately
sensing the comfort level in the living area.