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TEMYS on Sun August 04, 2013 4:45 PM User is offline

Year: 1989
Engine Size: 3.0
Refrigerant Type: R134A CONVERTIO
Ambient Temp: 80
Pressure Low: 60
Pressure High: 50
Country of Origin: United States

My 89 Chrysler New Yorker ac was not working for a while so i decided to overhaul it.
Remanufactured compressor,,new expansion valve,,new drier,new switches new accumulator,,new fuses ,,new relay.
converted to R134A fittings.
Properly evacuated and disposal of Fremont,,,flushed,,no leaks.
Proper amount of oil on the compressor.
Hooked up manifold gauges,,, Put ac on and star recharging with R134A as specified 80% but clutch didn't engage so jumped clutch and engaged,,,, low pressure went to 60 high pressure 50 blowing warm air.

Removed hoses and not clogged,,Got another remanufactured compressor and another new expansion valve,, Purged air from manifold gauge hose,, Recharged again but still low pressure 60 high pressure 50.
Jump started compressor clutch kicked on but same thing blowing warm air.
don't know what else to do.

Jag987 on Mon August 05, 2013 1:25 AM User is offline

I'm no expert, still learning every day, but when I see a low that is higher that the high it seems to point to the compressor. Personally, I am not a fan of reman compressors. Curious though, what do the gauges read when the system is off? I would expect both sides to be above your posted numbers with it off, suggesting an under charged system. But like I said first, I don't claim to be an expert.

I bought a can of 134a at w**-mart that had a stop leak, oil, and dye in it. It also had a hose and a gauge, so now I'm an AC pro!

mk378 on Mon August 05, 2013 8:49 AM User is offline

Make sure you're using the manifold properly -- valve wheels are to be CLOSED to get a pressure reading.

If pressures are being measured properly, it does sound like you got one of those fancy "rebuilt" compressors that is actually just a good paint job and DOA inside.

The pressure should be higher than 50 or 60 in any case. You have precious little refrigerant in the system. How are you measuring how much you charged?

Edited: Mon August 05, 2013 at 9:16 AM by mk378

webbch on Mon August 05, 2013 2:58 PM User is offlineView users profile

Definitely sounds like an equipment issue to me as well...I'm assuming you pulled a vacuum on the system before charging.

While charging, the center hose on your manifold goes to you can or tank of refrigerant. The high side valve on the manifold should be closed and the low side valve should be open to allow the low side (suction line) to pull in the refrigerant. You do NOT want BOTH the high and low side valves on your manifold open while charging. Apologies for the elementary suggestion if that is not the issue.

Edited: Mon August 05, 2013 at 3:11 PM by webbch

Chick on Fri August 23, 2013 11:49 PM User is offlineView users profile

Did you pull a deep vacuum and recharge into the vacuum?? Sometimes "evacuate" to some people mean they just removed the refrigerant...
Also, as stated when charging the high side valve must be closed...
let us know exactly what you did and how....
hope this helps..

Email: Chick


Freedoms just another word for nothing left to lose

Leggie on Tue August 27, 2013 3:07 AM User is offline

Assume your gauges read correctly and temperature readings are correct.
If standby pressure at 80F is not below 86 psi (find the temp to press relationship with a chart), you don't need to diagnose any further to know that its a total refrigerant loss.

Pull a vacuum and test for air ingestion. If you pass this, pressurize system with CO2 or N2 to 150 psi and test for pressure loss. I expect you'll hear a strong hissing with the rate of leak you have.

This will not harm the low side at all, because the entire system is always at the same pressure when it is idle and when ambient is 110F, this pressure is about 150 psi. Therefore, the system is designed to withstand this level of pressure.

Vacuum tests only tests the system for leak at 15 psi inward pressure, which is not a condition normally encountered. Nitrogen pressurization allow for outward testing. You can't use refrigerant for this testing, because its tendency to absorb into oil or liquefy under pressure cause false readings.

I suspect that you forgot an o-ring somewhere or incorrectly assembled something somewhere that holds up to -15psi, but lets out like a pressure relief valve under positive pressure.

Jump starting a compressor is a stupid idea in 99.9% of the case. You need to measure the high side and confirm that there's adequate pressure first, then test the low pressure cut out on high side electrically. If the switch is not functioning, recover the charge. Remove the sensor, then pump nitrogen into the system. Confirm air sprays out of the sensor port to rule out clogging.

At this point, you know the sensor is bad.

if sensor is acting properly... you may jump the compressor carefully for testing purpose, but observe the gauge so that it does not drop below 50 psi or so on high side, ever.
Verify that it cools. At this point, you start chasing down the control systems for malfunctions. (severed wires from collision damage, fuses, abusing harnesses, misassembly, etc)

Originally posted by: Chick
Did you pull a deep vacuum and recharge into the vacuum?? Sometimes "evacuate" to some people mean they just removed the refrigerant...

Also, as stated when charging the high side valve must be closed...

let us know exactly what you did and how....

hope this helps..

That's if the car is running. I prefer to shoot liquid refrigerant into high side as liquid to prime liquid(keeping track of how much goes in still...) into condenser and allow the pressure to build up for low pressure cut out to close. Close high side. Wait for equalization. This prevents the compressor from hunting on and off repeatedly when its turned on which can damage the clutch.

Patiently charge the system through low side as vapor. I strongly advise against liquid charging into low side, especially on a TXV system with the low side close to the compressor, because of the possibly of hydrolocking which will destroy the compressor instantly.

An orifice tube system with the port on suction accumulator or to the evaporator side of it is much more forgiving of liquid charging, but I prefer not to do it.
When you liquid charge, there is no phase change in the can/tank, so it will go in faster whereas vapor charging causes tank to cool from refrigerant boiling in container that can slow down the charging process, but this can be overcome by doing it slowly with patience.

Edited: Tue August 27, 2013 at 1:47 PM by Leggie

wptski on Tue August 27, 2013 1:14 PM User is offline

Moderator, please delete!

Edited: Tue August 27, 2013 at 4:43 PM by wptski

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