About parallel compressor system

[ernestlin]

Could any advance pal who is good at parallel (semi-hermetic) compressor system do me a favor? what's the sticking points we should pay more attention to when designing parallel condensing units? And where can I get more practical information about it? Extremely grateful to your reply!

[Peter_1]

http://www.refrigeration-engineer.co...ht=bitzer+pack

[TXiceman]

The big problem with paralleling compressors is oil return. You need to get the oil back to the compressor that needs the oil.

Ken

[US Iceman]

Oil return and equalizing between the compressors are the major issues.

A secondary issue is to pay close attention to the discharge piping so that two discharge lines are NOT bull-headed in a common discharge line.

A bull-headed connection is one where two discharge lines are piped into converging flow into a tee. (both are piped in the "run side" of the tee. One from the right, one from the left)

In this case, the common discharge line would be piped from the tee outlet or "branch" connection.

This is not what you want as this can create additional vibration in the discharge lines. I've seen this break copper lines very quickly, so I don't recommend this type of piping arrangement.

[ernestlin]

Tks a lot! Peter, ken and Iceman. You give me a big help.