York HIDS006B21S Service Manual page 63

Other
Abnormalities
Event
Insufficient
Heating
Operation
SM-18001-rev.1
Cause
Indoor Heat Load is Larger
than Heating Capacity
Gas Leakage
or Insufficient
Refrigerant
Charge
Excessively
Small
Diameter or
Long Piping
Failure or
Malfunction
of Electronic
Expansion
Valve
Clogging of
Indoor Unit/
Excessively
Outdoor Unit
Low
Strainer
Suction
Pressure
Clogging
of Suction
Piping
Insufficient
Airflow to
Outdoor Unit
Heat
Exchanger
Excessively
Low
Air Temp. to
Outdoor Unit
Heat
Exchanger
Defrosting is
Insufficiently
Completed
Abnormalities of Devices
Check Item
Calculate heat load.
Measure superheat.
Measure field-supplied
pipes.
Check for clogging.
Check for connecting
cord and connector.
Is there operation
sound from coil?
Is thermistor on
compressor normal?
Is thermistor
installed correctly
on compressor?
Check temp. difference
between inlet and outlet
of strainer.
Check temp. difference
of each part.
Is outdoor unit heat
exchanger clogged?
Are there any obstacles
at inlet or outlet of
outdoor unit?
Is service space for
outdoor unit sufficient?
Check outdoor fan speed.
Check for any
Check for any
short-circuits short-circuited
to outdoor unit. outdoor unit air.
Check thermistor for
defrosting.
TROUBLESHOOTING
Action
(Turn OFF Main Switch)
Use larger unit.
Correctly charge
refrigerant after gas
leakage check and
repair.
Use specified pipes.
Remove clogging.
Replace connector.
Replace coil.
Replace thermistor.
Correctly install it.
Replace strainer for
outdoor unit or indoor
unit.
Remove clogging.
Remove clogging.
Remove obstacles.
Secure sufficient
service space.
Replace fan motor.
Remove cause of
short circuit.
Replace thermistor
for defrosting.
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