Service Diagnosis - Haier HSU-09HEG03/R2(DB) Service Manual

7.Service Diagnosis

7.1 Caution for Diagnosis
The operation lamp flashes when any of the following errors is detected.
1.When a protection device of the indoor or outdoor unit is activated or when the thermistor malfunctions,
disabling equipment operation.
2.When a signal transmission error occurs between the indoor and outdoor units.In either case, conduct the
diagnostic procedure described in the following pages.
7.2.Problem Symptoms and Measures
Symptom Check Item
None of the units Check the power supply.
operates
Check the indoor PCB
Operation Check the power supply.
sometimes stops.
Check for faulty operation
of
Equipment
expansion valve.
operates but does
not cool, or does
not heat (only for
heat pump)
Diagnosis by service port
pressure and operating
current.
Large operating Check the installation
noise and condition.
vibrations
Details of Measure
Check to make sure that the rated voltage is supplied.
Check to make sure that the indoor PCB is broken
A power failure of 2 to 10 cycles can stop air conditioner
operation.
Set the units to cooling operation, and compare the
the electronic temperatures of the liquid side connection pipes of the
connection section among rooms to check the opening and
closing operation of the electronic expansion valves of the
individual units.
Check for insufficient gas.
Check to make sure that the required spaces for
installation (specified in the Technical Guide, etc.) are
provided.
49
Service Diagnosis
Domestic Air Conditioner