Oil return in NH3 plants

[TXiceman]

More oil than i care to have drained.....

Your point on mixing oils is dead on....not a good idea even if the rep says/NO PROBLEM.

I have seen a lot of problems mixing oils which were supposedly compatible, especially mineral base and synthetics. If you star having oil problems, the best thing to do is dump all of the oil, drain every low point and charge with fresh oil. Run for about two weeks on the new oil and dump all of the oil collected in the oil puts. Now dump this oil and recharge again. Continue dumping the recovered oil until it starts to come back clean. I have seen plants where we had to dump the oil three times to get it cleaned up.

If you stay on top of the maintenance, and keep the system tight and clean...oil should not be a problem.

The two places I see the system getting contaminated is :
1. sloppy oil charging. Leaving a opened barrel of oil out with water on top of it and not sealing the oil charging hoses.

2. Sloppy refrigerant charging. Same thing, not keeping the hose sealed or cleaning it before it is used.

My personal hoses and gauge set have the hoses closed all of the time. I open them and clear with some dry nitrogen or refrigerant if any question.

I have seen system operating over 20 years and the oil system is still clean. The oil is one of if not the most critical things in the system. Poor oil system and you will have compressor problems.

So if you have a dirty system, drain the recovered oil and dispose of it until you can do a proper oil change and flush.

I have seen some systems so bad that we had to do a chemical flush on the piping and then you have the problem of drying the system from the water in the neutralizing flush.

You let a system get in bad shape and it is a major head ache to clean it up. Trying to limp along with patches and adding any old oil will finally come back to bite you in the rear big time. It is just a matter of time.

I preach maintenance...maintenance....maintenance.

Ken