3 replies to this topic

[LLAMBERT]

Heres the digits. air temp before the coil 75, past the coil 65. R22 pressures low side 74, high side 210. Had the ducts replaced. Insulation added is next step. unit about ten years old any thoughts?

[Dan Webster]

75 PSI has it lugging.. With the house cool you oughta be around 68 PSI

Edited by applianceman18007260692, 02 August 2011 - 08:57 PM.

[LLAMBERT]

thanks, I'll adjust it. house itself is 78-90 not cold enuf for swmbo.

[ACtechGUY]

75 PSI has it lugging.

SAY WHAT?? HUH?? What you talkin' ' bout Willis???

R22 pressures low side 74, high side 210

Suction pressure of 74# is normal for a 75 degree air temp . No problems there.
Head pressure of 210 is low if it was hot outside, and I can guess it was really hot outside like in the 90's.

Here are some general rules of thumb for R-22.

At 95 degrees outside you will see somewhere around 275 # head pressure. maybe just a bit lower for a higher efficicancy unit.

Suction pressure often mimics the entering air temperature . If you have 75 degrees entering air temp , your suction pressure will likely be somewhere near 75# psi. Weird but often true.


You need to confirm what type of metering device you have. If you have a piston or cap tube metering device , you may have a " Partial No Pump " compressor. The symptoms are low head pressure (in relation to the outside temp),along with a higher than expected suction pressure ( in relation to the inside temp)


If you have a TXV (thermostaic expansion valve) , you may be simply low on refrigerant. With txv's you can have a high suction pressure when you are low on charge. One indicator of low charge is low head pressure . I would expect to see higher pressure than 210 when it is very warm outside .