Evaporator Oil logging

[Lord Raiden]

Took a look at a split heat pump, where the compressor was located 20 feet higher than the air handler. No p-trap on the air handler and unit has a history of compressor change-outs. 4 already, current compressor is nosiy like hell and vibrating. So all the symptons of oil logging. I installed an oil separator on the unit, and a p trap on the suction line, unit is working fine now. However, I'm still concerned about the amount of oil still in the system. This unit currently has 150 feet of piping in a commercial occuped environment, too late to make piping changes other than the p-trap. Is there a way of getting out all the oil in the system and how please?

[Phase Loss]

the oil should come back if you have good velocity just give it time.

or take a drill and a bucket at the lowest point and drain it out. but not first of course.

[kim]

Best way to get oil to return: add heat. If you have oil return problem with a reverse cycle system, you have a big problem.

I would try to set the defrost to the 45 minute setting. Have not done defrost in a while, so it is probably demand defrost. If so, never mind.

[uguysagain]

you should be fine by adding the p trap jus give it time and double check in a few days

[captinsano]

check with manufacturer about the suction line size if it is too large you wont get velocity up to return oil also any horizontal piping runs should slope towards the condensing unit hope this helps.