# Compressor oil



## goldmoona (Sep 19, 2019)

​Two outside condensing units, one for normal operation and the other for emergency operation are connected to indoor air handling unit with a single copper tubing. Someone questions about the possible accumulation of air compressor oil into one of the condensing unit, which may cause damage of the compressor. Please let me know it is true and how to resolve the problem.​Please answer the question. Thanks so much. ​


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## wakeforestseptic001 (Feb 20, 2020)

Hi, when the compressor restarts, the sudden drop in pressure in the crankcase will boil the refrigerant causing the oil/refrigerant mixture to foam violently and forcing the oil out of the compressor and into the system. Once in the system, the oil must travel the complete circuit before it can return to the compressor. Hope it helps.

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Joel - Wake Forest septic service


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## wakeforestseptic001 (Feb 20, 2020)

Hi, when the compressor restarts, the sudden drop in pressure in the crankcase will boil the refrigerant causing the oil/refrigerant mixture to foam violently and forcing the oil out of the compressor and into the system. Once in the system, the oil must travel the complete circuit before it can return to the compressor. Hope it helps.

____
Joel - Wake Forest septic service


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## Sm_raudales (Jan 18, 2021)

Reciprocating compressor lubrication.

Reciprocating compressors can be viewed as two distinct groups: single-acting and double-acting machines.

Smaller, single-acting units are typically splash lubricated. Temperatures of 400 F in the compression cylinder can be expected. There is typically no filtration and the same lubricant functions throughout the unit.

The lubricant in these units sees relatively severe thermal stress. Due to small sump sizes, high temperatures, moisture accumulation, and lack of filtration, fluids with good antiwear properties are normally employed.

Most large, reciprocating compressors are of the double-acting type. A crosshead isolates the cylinder, where compression occurs, from the sump, allowing the utilization of two different lubricants to meet the specific needs of each location. The sump of the double-acting machine is a mild environment and hydrocarbon oils are typically used there.


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## chrstopher007 (Mar 27, 2021)

when the compressor restarts, the sudden drop in pressure in the crankcase will boil the refrigerant causing the oil/refrigerant mixture to foam violently and forcing the oil out of the compressor and into the system.


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