Mitsubishi Electric problems

[johno12345]

Hi,

I have a PUH6YKSA mr slim split air conditioning unit that im having problems with.

So far I have only ascertained the following:

It trips the breaker C16 (not sure if this is a red herring though)

when it runs, the outdoor unit fans go at full belt

the gas and liquid lines are both hot but touchable.

It sometimes shows error P8 which seems to cover almost everything.

its installed in a warm area so im not sure that the heat i feel is just what has conducted onto the pipes.

There is another identical unit adjacent running fine. the only other thing is that this is running R417 refrigerant.

Any suggestions what to test?

thanks :)

[martinw58]

p8
Abnormality of pipe temperature
this is the indoor pipe sensor if the temp dose not change or goes the wrong way it will show p8 fault chech 3 way valve have you checked the gas charge
have you fitted gauges and checked the running pressures you can not check the unit buy touching the pipes

[install monkey]

above thread is referring to the puhz p8 error
puh6 is r22 system and relates to outdoor abnormality
1. SERVICE DATA INDICATION BY SWITCHES ON OUTDOOR CONTROLLER BOARD
Setting dip switches SW2 and SW3 on the outdoor controller board enables LED to show the output state and check code.

Output state is shown by LED lighting, and check code by blinking led. press sw2 check the back of the cover for the fault.
if the circuit breaker has tripped and the indoor & outdoor are seperatly powered then if ur comp is failing or breaker is weak then the breaker trips and u get a p8 error as the outdoor is inoperable.
check for water in ur isolator or a chaved cable.

[johno12345]

ok,

had a look at the leds and it says the compressor and fans are running. the fans definitely are but i cant hear or feel any vibration from the compressor.

I think it has a leak, i can see bubbles escaping from the flare nut on the gas line.

Presumably, there is no refrigerant in it, id have thought it would show a low charge error though or will it just stop the compressor from starting?

[install monkey]

some mitsi units alarm on p8 indoor temp hasnt changed in 20 mins and also compressor overheat is common too with loss of gas. the leds when lit show the status of the outdoor unit. normally led8 lit indicates crankcase heater energised. press psw2 and any blinking leds indicate the fault symptom,but a bubling flare nut is also a good sign.