I’m
stumped.
I set up the vacuum pump and tried to pull and hold vacuum in the lines. The set up is shown in the photo.
I tighten all the adapter and hose fittings as much as my fingers will, open the blue knob, turn on the pump. Gauge goes to -30 inHg right away. Vapor comes out the pump exhaust, fine, but the vapor never stops coming out which is weird? I run the pump for 15 min, then with the pump still running I close the blue knob, and the gauge immediately goes to zero i.e. the indicated vacuum is instantly lost. I try again, running the pump for 30 min, same result. I check torque on all flares, at the outside unit and at the indoor units. Lube the O-rings in the fittings, retighten them. Try again, same result.
I must be doing something wrong. If there were a big leak, the gauge wouldn’t go to -30 inHg right away - ? If there were a small leak, the gauge wouldn’t go to zero right away - ? Vapor indicates air moisture in the line boiling off, but it should stop eventually - ?
Tried both indoor unit lines, same. Okay, I can’t have screwed up both lines the same way - ?
Am I missing something obvious?