Compressor failure galore

[frankv1@maltane]

Hi Guys

A brand new 32HP VRF with one inverter compressor and four fixed speed compressor trips on alarm indicating the inverter compressor is in overcurrent.
The electronics are checked and found to be ok.Eventually the inverter compressor is changed.A few weeks after the replaced inverter compressor goes to heaven with the same overcurrent problem
as it's predecessor.They change the compressor again and again it fails. At this stage i was called in
and took two of these failed compressors to the workshop. On draining the oil it was dark smelly and had traces of fine metal particles.On cutting open the head (Hermetically sealed scroll),and removing the scroll i found the top floating bearing and shaft
badly scored with signes of welding and deep pitting.
The system on this unit has about 18 indoor units and is rather long.Any suggestions as to what i can do to either clean it or if filter driers will be enough.
The original compressor must have contaminated the system and the other failures followed and added more junk in the system.All electric motors are ok.
I am also curious why the inverter compressor always ended up worse as there is enough load for all the compressors to run.

Fra

[Brian_UK]

The inverter will run all the time and be inmvolved in system pumping exercises.

You should also check the fixed speed compressors because the oil is shared.

[D.D.KORANNE]

looks like system hygene problem , compressor is only the victim .

[frankv1@maltane]

If ever there was need for a lesson on the effects of contaminated oil on 410a systems this was it. The two inverter compressors i cut up showed the same problem.No mechanical or electrical failure . There was enough oil in the compressors so the only thing left was in fact system hygene and not proper vacuuming the system.
What a horrible way for two beautifull machines to go.

Fra