Hello all,

About two weeks ago I had serviced a water cooler that uses a Danfoss Maneurop Model MT144 that uses R22 gas and 160p mineral oil.

The water cooler has been sitting unused for 18 months, and there is no way to know when was the last maintenance and how old it is.

As the technician opened a valve to let the gas out (to the free air ) some oil dripped from that valve and I asked if that was normal, the technician shrugged and said that yes.

Now the water cooler seems to be working well and the temperature of the water in the pool is maintained at the correct level. There are no strange sounds and the compressor seems to be working smoothly.

But later, I told to a friend (who works with natural gas powered refrigerators) about the oil that is apparently mixed with the gas and he said that that is the indication of an internal leak and that could be a serious problem.

Well, as may be clear at this point I know next to nothing about those compressors and would like to know if someone out there who knows about this stuff could clear a few doubts:

1)is the oil in the gas normal? Is that the indication of an internal, dangerous leak? why?

2)how often should the compressor be maintained? the answers from the different people I've asked range from 6 months to 1 year.

3)The oil and gas must be changed at the same time always? some said that only the gas must be changed.

4)What else can I easily check to make sure that the compressor is ok?

What else should I know about those machines (which are to me surprisingly complex)? I'm afraid that I could be easily lied to due to my ignorance.

I've read your 101 but I think that that wasn't that helpful.

I'll give any other information that is needed.

Thanks in advance!