Mitsubishi Electric PUHY-P168, Service Handbook

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[
IX
Troubleshooting ]
Refer to section -8-"Inverter " under part [4] "Trouble shooting principal parts" for error codes related to the inverter.
4240
4245 Overload pro-
tection When the greater output
current (Iac) than the
Imax (Arms), or THHS of
more than 90 °C [194°F]
is detected for 10 min-
utes in a row. (1) Short cycle of the air pas-
sage
Check that the waste heat from the
outdoor unit fan is not short cycled.
(2) Air passage blockage Check that the heat sink cooling air
passage is not blocked.
(3) Power supply Check whether the power supply
voltage is 187V or more.
(4) Faulty wiring Check for cooling fan wiring.
(5) THHS failure Check for THHS sensor resistor.
In the case of 4240: THHS1
In the case of 4245: THHS5
(6) Compressor INV board
failure and cooling fan fail-
ure
Check that a voltage of 208/230V is
applied to the compressor INV board
connector CNFAN while the inverter
is in operation.
(7) Cooling failure Check the cooling fan operation un-
der the above operating conditions.
(8) Current sensor (ACCT)
failure
Refer to 9 [4]-8-(4).
"Current sensor ACCT"
(9) Compressor Inverter cir-
cuit failure
Refer to 9 [4]-8-(2) [4].
"Check whether the inverter is dam-
aged".
(10) Compressor failure Check that the compressor has not
overheated during operation.
-> Check the refrigerant circuit
(oil return section).
Replace the compressor
when no fault is found.
Error Code
Error definition and error
detection method
Cause Check method and remedy
Imax
P72 model 40 Arms
P96 model 50 Arms
P108 model 50 Arms
P126 model 50 Arms
P144 model 53 Arms
P168 model 50 Arms
P192 model 50 Arms
P204 model 50 Arms
P216 model 53 Arms
P234 model 53 Arms