Mitsubishi Heavy - Help needed Urgently

[marc5180]

Been called to a nightmare job down in London its a Mitsubishi FDC 2501HK XE2 condensor with 5 indoor fan coil units got called to an E46 fault high pressure, Checked the gas pressures and found the unit pulling a vac i.e. no gas.

Pressure tested the system and found the suction line going in to the compressor hadn't been braised properly so braised it up and pressure tested it again and left overnight. Standing charge is 11kg but there is nothing on it to indicate additional charge. Vacced out and recharged with a standing charge. Got the unit up and running, suction pressure was at 7 bar (r22) and the discharge was at 11 bar compresor sounded squeely and didn't sound too healthy. Took the amps which were 18/19.

All of a sudden the unit switched off and on the main PCB board LED1 started to flash also on what looks like the inverter board LED3 is flashing, gone to the controller everything seems to be fine as nothing is flashing.

Took terminals off the compressor and checked the voltage was getting 28v ac with them disconnected, reconnected and the red lights on the board started to flash indicating a fault, on the controller there is no fault.

The compressor hasn't run for about an hour, but over the past few minutes the side of the compressor is 40oc and to hot to touch. The compressor is making a squeeky noise for less than a second every minute or so, I'm leaning towards a faulty compressor but want to be sure before I condem it!


There are no wiring diagrams at all

[Brian_UK]

Sounds like you're right on the dead compressor.

If you had a leak on the compressor suction and it had been running towards a vacuum then 10 to 1 that air has been drawn in and it's wrecked the windings or oil.

[marc5180]

I thought so, it isnt down to earth which i thought it would have been . Iv ordered a new compresssor today for it so il post back when it arrives.
Thanks Brian.

[marc5180]

Compresssor has finally arrived and im down to do it wednesday morning so im hoping all goes well.

[expat]

Marc, just a little thing, 40°c is not too hot to touch. That's more like 65°c and above.

I'm only saying this because if you took the temperature with a metre of some sort then it wasn't reading correctly.

[marc5180]

Marc, just a little thing, 40°c is not too hot to touch. That's more like 65°c and above.

I'm only saying this because if you took the temperature with a metre of some sort then it wasn't reading correctly.

Maybe i wrote down the wrong temperature, cant remember what it was now but it sure was hot to touch.

Fitted the compressor last week and its been running great ever since.
Thanks

[Brian_UK]

Good job Marc, just don't turn your back on it yet