Troubleshooting help needed-AC pressures
OK, now I understand how these gauges work....I'm a complete IDIOT!
I found a cutaway drawing... All right, I need to re-evaluate my situation as I probably messed it up. So my manifold valves were open but the charge hose was parked on the manifold so I'm not sure if it mattered or not if it was open because the fill hose was not hanging open to atmosphere?
YEH!! IT MATTERS!!! This is a standared 2 gauge manifold with 2 valves and 3 hoses? To only measure pressures, CLOSE both manifold valves. The ports from the hoses go straight to each gauge.
When you open either valve, the center port is now connected to that hose and gauge. So with both valves open, "everything" is interconnected
Here's how I do, "let's say" you have it all charged up and running. If we have schrader (tire core) service ports, I use what is called a "schrader controller." This is a rig that looks like a small valve, goes on the fitting, your hose goes onto the controller.
If you have service ports with closeable ports (valve stems) you don't need that
So, "let's say" you have it all charged and running good. You don't want to waste refrigerant, so here's how to unhook. Both manifold valves are closed. You have purged the hoses on hookup, and the charging can is sitting there on the third port empty.
Unhook the charging can, hook the middle hose to the storage fitting on the manifold. Crack the low side valve and purge the middle hose to the storage fitting, then tighten. Now the manifold is again purged and leak tight
So now close the high side service valve, or back off your Schrader controller. Then open the hi side valve, and next, slowly open the low side valve. This causes the compressor to suck everything in the manifold/ hoses, into the low side. There will of course be "low side pressure." Let it set a few seconds to evaporate liquid. Then close valves, close off the low side if needed, and disconnect the hoses
Connecting. I usually try and connect before turning on system. Of course if charging/ evacuated this does not apply. Make sure manifold valves are closed, hose fittings tight, and third hose tight at storage fitting. Connect hoses, open low side service port, and purge by opening low side valve, purge through center hose by loosening at the storage fitting, and then open hi side valve and purge out to end of hi side hose by loosening hi side hose at service port. then close both manifold valves, make sure all hose/ fittings are tight, and open hi side service port.
Again, MAKE SURE both manifold valves are closed
