Haier HSU-18,22HVA103/R2(DB) Service Manual page 86

（A）
Check the status of LED1 on
the indoor mainboard. If the
LED1 blinks interruptedly？
No
Test the outdoor power supply
(230VAC and +310VDC) with a
multimeter.
If both 230VAC
310DC
available,measure
YES
If the LED1 is off within two minutes
after the machine is supplied with
power, measure the AC voltage between
positions 1 and 3 on the terminal of
outdoor unit with a multimeter.
If the value varies between 0 and 80
VAC, the outdoor mainboard is
damaged, replace it with a new one.
HSU-18,22HVA103/R2(DB)
If 230VAC is available but
310DC not, the power module is
damaged, replace it with a new
one.
and
NO
are
The outdoor mainboard is damaged;
Replace them with a new one.
Yes
measure the voltage between Jumpers
3 and 4 of IC15 on the indoor
mainboard with a multimeter.
If the voltage is of a
constant value of 0V
The indoor mainboard is
damaged; replace it with
a new one.
If the value is constant at about 30V,
the indoor mainboard is damaged,
replace it with a new one.
The outdoor mainboard is damaged;
replace it with a new one.
85
Service Diagnosis
NO
Yes
Domestic Air Conditioner