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.