AC Suddenly Stopped - Pressure/Fuses/Relays/Switches Fine

[sgtsandman]

Hopefully, there isn’t dye blown everywhere and you can see when it actually leaked from.

 

[Snoranger]

I'm guessing you're right since the AC has now started to not blow very cold. I'll hook up one of my recharge bottles and see if it'll take some refrigerant and improve. If that's true, it means I have a leak somewhere. Not sure how or where since the shop said it held vacuum and recharged fine. Maybe I didn't get something connected tight enough? I know they put some UV dye in so maybe I'll get one of those lights to check...

Holding vacuum and holding pressure aren’t the same thing. Ive had plenty of systems that passed the “leak test” (hold vacuum for a set amount of time.) but won’t hold pressure long term.

 

[Spidey300]

Hopefully, there isn’t dye blown everywhere and you can see when it actually leaked from.

So I just went out to look at it. I hooked up my recharge kit to the low pressure side with the ac running and I could watch the pressure rise and fall as the compressor cycled. The needle would climb up to about 45 psi then the compressor would kick on and it would drop over a couple seconds down to about 15psi at which point the compressor would disengage, climb back up to ~45 then repeat the cycle. We're talking on for ~2 seconds, off for ~3 seconds.

I didn't try adding any refrigerant since this seems like the system pressure isn't the issue, so not a leak but maybe a blockage somewhere?? Of course, this was a cheap gauge off a recharge bottle and not the most accurate.

EDIT - don't have the UV light/glasses to check for leaks yet.

 

[Uncle Gump]

What you just saw on your gauge indicate a low charge. As hot as it is today... low side pressure should never fall below the low pressure cutout switch threshold.

 

[Spidey300]

What you just saw on your gauge indicate a low charge. As hot as it is today... low side pressure should never fall below the low pressure cutout switch threshold.

Well, you were right. It was low. I added the r134a recharge cans that I had (maybe half a pound?) and got the compressor to stay on and air to cool down. Got it to the point where it wouldn't really take anymore refrigerant even though it seemed I had some in the can still. pressure was reading around 30 psi with the compressor running. With today's heat (near 100 ambient) it seems like it should probably take more but it didn't seem like it would. I guess I'll get that uv light... fingers crossed it's just a loose connection...

 

[Uncle Gump]

If you can get duct Temps roughly 30 degrees cooler then ambient... you're pretty close to full.

 

[Spidey300]

@Uncle Gump @sgtsandman Is this leak bad enough to be causing my issue? It was the only thing I really saw. There was some oily residue I could wipe away. If so, I'm kinda passed cause this was a new accumulator.

 

[sgtsandman]

Yep. Any leak in the system is bad. See if you can get that replaced under warranty. Assuming it isn't one of those 30 day deals.