404a Oil Problems

[sefuss]

Hi guys

I seem to experience more oil pressure problems on 404a systems than any other refrigerant type commonly used.

Does any one else notice this with 404a systems and could any one possibly explain the cause/reason

I have double checked the type of oil used is correct and all strainers/filters are clean and changed on a regular basis, yet over the past 12 months alone i have had 4-5 oil pressure faults on different sites that come in as repeat calls

All faults have been on recip compressors

cheers guys

[oldesky]

there are other threads on this issue but to recap the oil problem may be caused by liquid migration into the crankcase. This will cause the oil to foam and cause the oil pump to stop working as many cannot pump the oil foam. The trick is to find and prevent the cause of oil foaming.

[joe magee]

I have lots of 404a racks. No oil issues. I would look for floodback. Is this a single or a parallel system? Low temp or commercial temp?

[Magoo]

Hi sefuss,
are your problems with new installed systems, or retro-fit changes.
Cannot say I have had any oil issues with systems that I am envolved with to date.