- 95 -
Error code check
Error number
Errors
Meaning
Main cause of occurrence
151
(11
→
511)
Outdoor unit 4 way
valve switching
error
Outdoor unit 4 way valve
switching failed
1. 4way valve malfunction by entrance of foreign object
2. No high pressure/low pressure difference generated due
to damage of the compressor
3. Incorrect installation of the common pipe between outdoor
units
4. 4way valve unit defect
n
How to diagnose the disorder
Connect the 4way valve coil again
Refer to error 51 and take action
Yes
Yes
No
No
Replace outdoor unit PCB
Yes
Connect the connector again
Replace 4way valve coil
Yes
No
No
Yes
No
Yes
No
Yes
No
Replace 4way valve (Note 5)
Is 4way valve
connector correctly
connected?
Is 4way valve coil
resistance value
normal? (Note 1)
Is 4way valve coil
correctly connected to the
wary valve? (Note 2)
Does master outdoor
unit recognize the slave
outdoor unit? (Note 3)
Is 220V measured at
PCB when heating starts
after reset? (Note 4)
After operating in the opposite
operation mode from the
current operation mode, does
the error occur again?
Does compressor
properly operate?
Check and replace compressor,
magnet switch, and the corresponding
PCB (Electronic parts)
If the same error occurs again in the
future, replace 4way valve