Oil equalization line importance in parallel rack

[coldseek1]

Good afternoon fellows. In the past, I´ve seen racks with and without oil equalization lines connecting oil level regulators. I did not understand why. Just recently,a maintenance supervisor asked for the elimination of that line in an old low/médium temp rack, since she is afraid that discharge pressure by-passing to the crankcase of any worn compressor, might go through the equalization line and overpressure then blocks suction oil return in the remaining semihermetics. Would that be the reasoning behind the diference in preference between rack manufacturers?

[mbc]

Hi
As you know equalization oil in racks system in very important
There are many different types system to do that
Common oil separator or separate oil separator
And different type of oil connections
But in all of them each compressor should have own check valve in discharge line
The reason of that is
If one compressor loses discharge valve plate it prevent to bypassing gas through damaged compressor.

[coldseek1]

thank you MBC. I had heard about bypass of discharge into suction side through damaged valve plate, but haven´t understood purpose of check valves

[mbc]

Hi
The reason of that is
If one compressor loses discharge valve plate it prevent to bypassing gas through damaged compressor to the system .
and it is very important in designing to have that.