Haier MRV II - Page 127

Part 3
[39/31] low pressure protection acts
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if in cooling indoor
fan motor runs normally
if indoor heat exchanger
or filter is clogged
if the low pressure
sensor is in back up running
yes
no
no
yes
yes
clean
if connector, capacitor
and fan motor of indoor are
normal
modify
modify
no
no
yes
no
check indoor PCB,
if faulty, replace it
replace low pressure sensor
if the low pressure
sensor characteristic is
normal
yes
no no
no
no
no
yes
yes
yes
yes
yes
yes
yes
no
no
clean
if in hea ting outdoor
fan motor runs normally
if connector, capacitor
and fan motor of outdoor are
norm al
check outdoor PCB,
if faulty, replace it
if outdoor heat
exchanger is clogged
if outdoor gas/liquid pipe
stop valves are open
if the low pressure
sensor characteristic is
normal
replace low pressure sensor
if SV3 bypas s circuit is
normal
modify SV3 passby circuit
open all the valves
lack of refrigerant, clogged,
or pipe bended
confirm if there is clogged and
bended pipe, recharge the
proper refrigerant
yes
if wiring is correct
match the right wire