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Abe
25-05-2001, 06:22 PM
What would be the normal low side and high side pressures on a R22 air conditioning system with the folowing parameters

Ambient 30 Degrees Celcius
Remote Controller set at -16C

Gary
25-05-2001, 10:31 PM
Pressures are only meaningful when converted to saturation temperature, and even then they represent only a small part of the refrigeration or A/C picture.

If you want to understand what's going on in a system, you need the following:

High side saturation temp.
Condenser air in temp.
Condenser air out temp.
Liquid line temp at receiver outlet.
Liquid line temp at TXV inlet.
Low side saturation temp.
Evaporator air in temp.
Evaporator air out temp.
Suction line temp near compressor inlet.
Suction line temp at TXV sensing bulb.

All of these variables affect pressures.

Brian_UK
26-05-2001, 11:33 PM
As Gary correctly said there is a lot a information required before you can state what is correct for a given system.

However, think on this - you are only trying to cool air not freeze it so what 'range' of low side pressures would you expect?

Also, most important - - it doesn't matter a rat's ar*e what temperature the remote controller is set at :D

Jack Lester
01-06-2001, 02:15 PM
Perhaps I missunderstand your aplication but here are some thoughts Abe. I asume your remote control is controlling the temp of the area to be cooled. -16c to me is a freezer which equates to 3.2F in the states. I usually figure a 10F degree TD thru the coil or the coil is 10 degress colder then the air. This means the coil would be -6.8F or -18.5C. look at the TP chart and see what preasure this is and check your gauges. Should be fairly close. If not check your superheat thru the coil. Of course there is preasure loss depending on piping but you can come close.

Abe
05-06-2001, 10:20 PM
Thank you Jack for your reply, stat is set at 16 c and not minus 16
I have info now to go on so thanks a lot
As they say you learn a little every day


[Edited by Abe on 05-06-2001 at 10:37 PM]