Haier HSU-18HVA103/R2(DB) - High work-intense protection

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