Quote: Originally Posted by igotdoo
That sounds reasonable. However, when the tech noticed that low high side pressure, he closed the high side valve with the gauges on, and watched the pressure not able to build.
I agree with darrell that a low head pressure is normal with restricted refrigerant flow. (Until the techs "fix" the problem by overcharging the system)
The high side valve closed for the test above..must be on the liquid line. Closing the liquid line valve will possibly raise the head pressure briefly but most likely, the head pressure will fall as the system pumps out the refrigerant in the low side into the condenser. In other words, the test mentioned above, produces normal results and does NOT prove a "bad" compressor.
Lynn Comstock, excellent on point points; You know how things work.
When it's acting up, using Superheat & Subcooling will also help reveal what's going on within the refrigerant system
I have very bad hands & fingers & unless I can use something from my pages, I try to keep typing to minimum. Have to get typing software fixed, can't load it now. Hick & peck type with eraser end of pencils, tons of typos to correct, very frustrating. - Darrell
Last edited by udarrell; 07-16-2009 at 07:13 PM.
Reason: Using SH & SC can be helpful...
I have checked out compressors that I have suspected valve problems by shutting down condenser at the outside disconnect then feel of the suction line if you feel it get warm then this means that the valves are leaking hot gas back from the high side.