Low side stuck

[andrew vanis]

Charging TXV system for a friend.

Yesterday pulled and held excellent vacuum of 320microns.

Last night put in 1/2 expected capacity to put in rest today during heat load. Low/high sides moved up/down as typical.

Today low side is stuck at ambient. High side moves up/down with RPMs. Verified gauge by opening fill line and low side bumped a bit and stays stagnant.

Compressor? TXV?...or something else?

Thanks

[tbirdtbird]

Sounds like the coupler is not fully engaged.
Did you leave the MSG connected all night?

[andrew vanis]

Sounds like the coupler is not fully engaged.
Did you leave the MSG connected all night?

Please define MSG.

Coupler - I'll conclude the quick coupling fitting.

How could coupler be not fully engaged? 1) It was holding pressure. 2) used it later that morning w.o issue on another vehicle.

Thanks

[andrew vanis]

Please define MSG.

If that is something like Manifold S? Gauges, then yes, had them connected all night

[JohnHere]

I think that means Manifold Gauge Set, or MGS. Fat fingers, probably.

[tbirdtbird]

Yes MGS, manifold gauge set.
Suggest to not leave MGS on overnight or for long periods. You can have slight losses thru the hoses.
You can have trouble with inconsistencies with the lower priced (read quality) couplers. We had trouble like that here until we switched to the pricier Robinaires. We have had posters with the same issues.

[Tim]

Yes MGS, manifold gauge set.
Suggest to not leave MGS on overnight or for long periods. You can have slight losses thru the hoses.
You can have trouble with inconsistencies with the lower priced (read quality) couplers. We had trouble like that here until we switched to the pricier Robinaires. We have had posters with the same issues.

Yep, in general. Those low-end gauge sets and couplers tend to fail. I try to push customers to a better set of gauges as they are nto that much more in the big picture. Not saying Poster is using them. I'm Just adding a general comment.

[tbirdtbird]

Plz send pic of your couplers. Need to be the kind that clip on, then have hand wheels to actually open the valve.
Need to be careful….seldom need to tighten the hand wheels all the way, just enough to get the needle to move. Sometimes if you tighten too much, you will loosen the shrader slightly when you loosen then handwheels. We have found it smart to check the tightness of the shrader cores after use of MGS using shrader tool.

[Cusser]

I bought a pack of seals for the inside of the service gauge hoses, as I'd lost a few (fell out). This has turned out to be a great idea !

[tbirdtbird]

Agree!!!