York YLPA R410a heat pumps killing compressors

[garyb]

Hi People

We have a site running 3x York YPLA heat pumps for a heated swimming pool complex. The site has been running for about five years and has been killing scroll compressors on a regular basis. There have been seven compressor failures now randomly spread across the systems. We have been cutting the last three open and have found in all cases that the bottom bearing has been failing which then causes the compressor to either seize or arc out to the stator. The packages are running on R410a with York V oil.

Has anyone had ongoing issues with the YLPA heat pumps?

We are wondering about the suitability of the oil and of the packages in general as they appear to be a chiller that has had a reversing valve thrown on and the badge changed from "Chiller" to "Heat Pump". The failures appear to be loss of lubrication and the oil seem to absorb a lot of refrigerant as shown when we try to pump out a compressor for replacement or pump away the oil out of the failed compressor. The logs aren't particularly helpful and don't suggest sustained floodback.

Any clues or experience other may have would be appreciated.

[RANGER1]

garyb,
Do these compressors have sump heater for when compressor cycles off?

[al]

Check your flowrates aren't changing when going from cooling to heating, superheat and subcool readings ok?

[HwT]

What is compressor model number? some manufactures recommends other oil viscosity when running in heat pump application