5. Trouble Shooting
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Items for
checking
Sub-items for
checking
Is the service
valve open?
Is the refrigerant
amount normal?
Is the fan normal?
(outdoor fan during
heating and indoor fan
during cooling)
Are the manifold
value and low pressure
sensor value the same?
(Is the low pressure
actually low?)
Check indoor/outdoor EEV / check indoor/outdoor unit PCB / check indoor/outdoor unit installation environment
: Do not replace PCB before EEV check.
: When EEV problem is found, replace EEV, and check normal operation of the product.
Is the strainer
part normal? [Note 1]
Is there pipe
leakage trace or
cracked part?
After welding/re-connection
of the corresponding part,
recharge refrigerant
Check and replace
related parts
Replace the strainer
After replacing
the outdoor unit PCB,
replace the check
low pressure sensor
Change the
refrigerant amount
(insert additional refrigerant)
Is the communication
line / pipe connection
normal?
Open the
service valve
Change
communication
line / pipe
Flow of trouble diagnosis
[Note 1] If the temperature difference
between before/after strainer is
severe and frozen state is visually
verified, or if the temperature
difference is verified, strainer
clogged status shall be
suspected.
[Note 2] If it is not entire freezing and there
is no freezing in front of the
strainer, sudden freezing in the
course shall be suspected.
[Note 3] After EEV check, if replacement is
required, replace EEV only, and
check normal operation.
! Caution
: Before checking PCB or various outdoor unit electricity flowing parts, start the checking 3 minutes after
power cut off. If it is measured in power supply stand by state, check the tester’s measurement mode and
be careful of the short circuit with parts other than the measurement part.
6.7 Troubleshooting Outdoor Error
CH 35 (Discharge pipe overheating error of Inverter)
