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Troubleshooting Water Source Heat Pump
To avoid electrical shock, personal injury or death, be sure that field wiring complies with local and national fire, safety, and electrical
codes, and voltage to the system is within the limits shown in the job-specific drawings and unit electrical data plate(s) .
Power supply to unit must be disconnected when making field connections . To avoid electrical shock, personal injury or death, be sure
to rigorously adhere to field wiring procedures regarding proper lockout and tagout of components .
DANGER
Low Voltage, check power
supply voltage
Fuse may be blown, circui
t
breaker is open
Wires may be loose or broken.
Replace or retighten wires
Unit Control, check thermostat
for correct wiring or bad thermostat
Neither Fan, nor
Compressor Runs
Unit
Compressor runs
in short cycle
Fan operates,
Compressor does not
Compressor attempts to start
but does not
Insufficient cooling or heating
Check compressor wiring for
defective wiring or loose
connection
Check thermostat for improper
location
Check for defective compressor
internal windings with ohm meter
Check for bad compressor
capacitor
Check for lock rotor amp draw
Check for proper air flow
. Filter
could be dirty
Check blower assembly for
dirt or bad fan motor capacity
Check for low refrigerant charge
Check amp draw on blower
assembl
y
Check capacitor
Check wiring - loose or broken
and check for bad
connection
Hi pressure lockout
-
A. Cool mode, check water flow
B. Heating mode, check air flow
C. Check reversing valve for
proper valve position
Check compressor overload
make sure it is closed
Check compressor to ground,
or for internal short to ground.
Compressor winding may be
open. Check continuity with
ohm meter
Check wiring - loose or broken
and check for bad
connection
Check relays and contacts,
also capacitor and wiring
Check high pressure switch
and low temperature switch to
see if unit is cycling on the safety
Check to see if the reversing
valve is not hung up and is
operating correctly
Check condensate overflow
switch in cool mode of operation