ideal economizer pressure

[stanthonycold]

Hi guys,

What would be the ideal economizer pressure for a screw compressor with suction pressure -37 c/4.7 " hg and discharge of 24 degree C/126 psig?

Thanks

[US Iceman]

The economizer pressure is determined by the location of the side port. If the port is closer to suction pressure the port pressure will be lower. If the port location is closer to discharge the port pressure will be higher.

This assumes it is for economizing only,not side loads such as evaporators or worse, hot gas defrosts.

If you are using a flash economizer a back pressure regulator is required to maintain the liquid feed pressure when the compressor unloads. Otherwise the liquid feed pressure form the flash tank will approach suction pressure.

[stanthonycold]

Thanks,this may be a stupid question but should the economizer pressure be the same as the operating compressor.Operating pressure is between 110 -115 psi which is about the same as economizer pressure which is around 110 psi.Is this right?I am new to the refrigeration scene so any help/tips you may give me will b greatly appreciated.The engineer on shift b4 me said that normal economizer pressure was 30 psi and now today it is gone up to 110 psi.what woulkd do this?

[US Iceman]

Several different things can cause the higher port pressure, but they all depend on how your system is configured. It could be evaporators defrosting ot something else.

Has it ever happened before? Unfortunately, this is not something that can be easily answered because I don't know what you have.:confused:

[stanthonycold]

lol,I figured it out anyways.It was a solenoid coil burned out on the inlet pressure regulator for the economizer but thanks just the same for the reply..