Help!!! Not your average A/C Issue
Thread Starter
Racer
Joined: Nov 2005
Posts: 410
Likes: 1
From: Amherst NH
Okay so I hooked the gauges up and got myself an infrared thermometer. With ac off the pressures match at ~55psi. With it on, now I'm getting 33L and only ~85H. Its about 65 regs out low humidity. Temps drops from 110-94 out of the condenser. Drops 192-165 passing the orifice filter. Its about 140 at the L port and about 155 in and out of the compressor. Vents are at 77.
Obviously this is a huge change in high aide pressure from when I took it to the shop. I troubleshot the gauges, they're good.
Standing by.
Obviously this is a huge change in high aide pressure from when I took it to the shop. I troubleshot the gauges, they're good.
Standing by.
Burning Brakes
Joined: Jan 2011
Posts: 1,067
Likes: 46
From: Springfield IL.
Oldtimer
Okay so I hooked the gauges up and got myself an infrared thermometer. With ac off the pressures match at ~55psi. With it on, now I'm getting 33L and only ~85H. Its about 65 regs out low humidity. Temps drops from 110-94 out of the condenser. Drops 192-165 passing the orifice filter. Its about 140 at the L port and about 155 in and out of the compressor. Vents are at 77.
Obviously this is a huge change in high aide pressure from when I took it to the shop. I troubleshot the gauges, they're good.
Standing by.
Obviously this is a huge change in high aide pressure from when I took it to the shop. I troubleshot the gauges, they're good.
Standing by.
Melting Slicks
Joined: Jul 2004
Posts: 3,092
Likes: 120
From: orlando florida
St. Jude Donor '15
Burning Brakes
Joined: Jan 2011
Posts: 1,067
Likes: 46
From: Springfield IL.
Oldtimer
You have to have head pressure for the system to work. Does the head pressure go up when you add gas? You are either very low on gas or the compressor isn't pumping. You need to weigh in the correct charge then trouble shoot from there. Head pressure will very according to outside air temp. Look on your gauges on the 134 scale, go up the scale till you find temp add 25 degrees then look at the pressure scale, that is the minimum for your system to work at.
Thread Starter
Racer
Joined: Nov 2005
Posts: 410
Likes: 1
From: Amherst NH
Got it! 
Pulled the condenser off and cleaned it. Put the system under suction for an hour and refilled it. Refilled it myself this time to ensure I was getting the appropriate amount of R134 and it is now blowing cold. Numbers are good for outside air temp and humidity. Both driver and pass vents are blowing low 30's temp.
Thanks to all who took the time to contribute. I'm happy I wont need to be swapping a new compressor.
Pulled the condenser off and cleaned it. Put the system under suction for an hour and refilled it. Refilled it myself this time to ensure I was getting the appropriate amount of R134 and it is now blowing cold. Numbers are good for outside air temp and humidity. Both driver and pass vents are blowing low 30's temp.
Thanks to all who took the time to contribute. I'm happy I wont need to be swapping a new compressor.
Last edited by nightman06; Mar 29, 2015 at 07:14 PM.
Le Mans Master
Joined: Feb 2012
Posts: 6,644
Likes: 479
From: OK
Got it!
Pulled the condenser off and cleaned it. Put the system under suction for an hour and refilled it. Refilled it myself this time to ensure I was getting the appropriate amount of R134 and it is now blowing cold. Numbers are good for outside air temp and humidity. Both driver and pass vents are blowing low 30's temp.
Thanks to all who took the time to contribute. I'm happy I wont need to be swapping a new compressor.
Pulled the condenser off and cleaned it. Put the system under suction for an hour and refilled it. Refilled it myself this time to ensure I was getting the appropriate amount of R134 and it is now blowing cold. Numbers are good for outside air temp and humidity. Both driver and pass vents are blowing low 30's temp.
Thanks to all who took the time to contribute. I'm happy I wont need to be swapping a new compressor.
Burning Brakes
Joined: Jan 2011
Posts: 1,067
Likes: 46
From: Springfield IL.
Oldtimer
Got it!
Pulled the condenser off and cleaned it. Put the system under suction for an hour and refilled it. Refilled it myself this time to ensure I was getting the appropriate amount of R134 and it is now blowing cold. Numbers are good for outside air temp and humidity. Both driver and pass vents are blowing low 30's temp.
Thanks to all who took the time to contribute. I'm happy I wont need to be swapping a new compressor.
Pulled the condenser off and cleaned it. Put the system under suction for an hour and refilled it. Refilled it myself this time to ensure I was getting the appropriate amount of R134 and it is now blowing cold. Numbers are good for outside air temp and humidity. Both driver and pass vents are blowing low 30's temp.
Thanks to all who took the time to contribute. I'm happy I wont need to be swapping a new compressor.
.
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Excellent!
Thread Starter
Racer
Joined: Nov 2005
Posts: 410
Likes: 1
From: Amherst NH
I pulled the condenser right out and sprayed/scrubbed the unit. It was pretty dirty on the outside. Plenty of junk jammed in there. I also flushed it out internally and did get some black residue in the flush fluid which I am certain is the remainder of damaged compressor which did not come out when I did a compressor swap 3 years ago. I'm not sure how much of the fix was cleaning that out and how much was me properly using the diagram to put in the CORRECT amount of r134. Either way, I will not be going back to that shop
Thanks everyone, you saved me the un-needed expense and effort of a new condenser and compressor.
Thanks everyone, you saved me the un-needed expense and effort of a new condenser and compressor.
Thread Starter
Racer
Joined: Nov 2005
Posts: 410
Likes: 1
From: Amherst NH
Okay, I may start a new thread depending on initial feedback but I've got a constant hissing now while I operate the A/C. I understand there MAY be a hiss at the system equalizes upon engine shutdown, but this is consistent while the ac is on. It sputters sometimes while operating but always hissing. This is new. Never had this before regardless of whether the ac was operational or not.
Too much r134?
Leak?
Bad orifice tube (just replaced it but maybe bad brand)??
Too much r134?
Leak?
Bad orifice tube (just replaced it but maybe bad brand)??
Burning Brakes
Joined: Jan 2011
Posts: 1,067
Likes: 46
From: Springfield IL.
Oldtimer
Okay, I may start a new thread depending on initial feedback but I've got a constant hissing now while I operate the A/C. I understand there MAY be a hiss at the system equalizes upon engine shutdown, but this is consistent while the ac is on. It sputters sometimes while operating but always hissing. This is new. Never had this before regardless of whether the ac was operational or not.
Too much r134?
Leak?
Bad orifice tube (just replaced it but maybe bad brand)??
Too much r134?
Leak?
Bad orifice tube (just replaced it but maybe bad brand)??
Thread Starter
Racer
Joined: Nov 2005
Posts: 410
Likes: 1
From: Amherst NH
I've got good hearing, but not this good. It's a clear hissing, clear enough that it takes two levels of speed on the vent to drowned it out. Locating the hiss is a little more difficult. From the drivers seat it sounds like it could be coming from the defrost vent. From the passenger seat it sounds like its coming from up under the glove box. I can hear it under the hood (barely) and it sounds like it is coming either from the drier area or behind the manifold (not visible).
The sound itself, as best I can describe it, comes on strong and steady for about 3-4 secs when I turn on the AC, then goes a little quieter and sputters. Then when I turn it off it picks up again to steady and dies off over about 7-8 seconds. This definitely sounds like pressure either bleeding off or equalizing. But why would it be doing it while its operating.
Bill, pressures read 34/205 @ 68 degs 70ish humidity and 2k RPMS.
The sound itself, as best I can describe it, comes on strong and steady for about 3-4 secs when I turn on the AC, then goes a little quieter and sputters. Then when I turn it off it picks up again to steady and dies off over about 7-8 seconds. This definitely sounds like pressure either bleeding off or equalizing. But why would it be doing it while its operating.
Bill, pressures read 34/205 @ 68 degs 70ish humidity and 2k RPMS.
Thread Starter
Racer
Joined: Nov 2005
Posts: 410
Likes: 1
From: Amherst NH
Definitely cant say without looking, but would that ONLY make a hissing when the AC is on? Because this hissing only happens in association with AC. It goes away completely in normal vent mode. Also, suction for the vent movement is good. No leaking there.