Need some advice on oils level an old semi hermetic trane compressor

RayWohlfarth

We inherited a Trane Semi Hermetic from the 1960's model 2F5A68 What is the old level supposed to be in the sight glass? Thanks for your help
Ray

pecmsg

Minimum 1/2. 

Max neat the top

pecmsg

and that’s while running. 

RayWohlfarth

Thank you I appreciate it

pecmsg

Sun 3GS was probably the oil. 

RayWohlfarth

You're the best thanks

MikeAmann

I don't know if this applies here, but Royal Purple makes a synthetic compressor oil.

https://www.royalpurple.com/product/synfilm-recip-100-reciprocating-air-compressor-oil/

EBEBRATT-Ed

@RayWohlfarth like a boiler sight glass. If you can see the oil level its safe to run.

optimum is usually half a glass as @pecmsg mentioned. The level will fluctuate if the compressor has unloaders opening and closing or multiple solenoid valves to feed multiple coils etc. Liquid tends to migrate into the oil which the CC heater is supposed to take care of, but you always get some. When the compressor starts the suction pressure and crankcase pressure drop so the liquid refrigerant in the oil flashes into vapor and drops the oil level momentarily. You can also measure the oil pressure at the pump and subtract the suction pressure from that reading to get the net oil pressure.

EBEBRATT-Ed

@MikeAmann that looks like air compressor oil not refrigeration oil

MikeAmann

EBEBRATT-Ed said:

@MikeAmann that looks like air compressor oil not refrigeration oil

That's why I said I'm not sure if it applies here. Thanks Ed.

EBEBRATT-Ed

@MikeAmann yes, I realize that now