Re: How to diagnose a bad expansion valve?

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> > > Retrofit included new filter drier, 8oz ester 100, vacuumed system down > to > > > 29 inches for 30 min. > > > > H'm. What'd you do about the oil in the compressor? Did you flush the > > system? > > No, the system was low on charge, barely recoverable, no flush was > performed. How critical is it to remove the old mineral oil?

It's not critical to remove all the mineral oil if you add more oil that is compatible with it, 134a, and your system. In a perfect world you would use compressed air or some other method to blow as much old oil out of the system as you could, followed by solvent, followed by evacuation. After evac, you can then add the refrigerant oil. I normally add mine with one of those little piston tools through the low side shrader valve so I don't have to break the system open.

> > 134a, but it reported air in the system, whatever that means, > > > > Noncondensibles (air, water and other contaminants) in the system severely > > reduce its efficiency. Air in the system means it was not sufficiently or > > properly evacuated, or that air was let back in due to improper charging > > procedure after a proper evacuation. > > > > > can't be more specific. Also in the retrofit, one can of seal > conditioner > > > > Usually not a good idea. > > Im toying with the idea that there is some sort of oobstruction in the > expansion valve, the type of seal condition wasn't the cliplight expoy shit, > but im still worried that the sealant might be causing some sort of problem. > One more thing...when i recieved the reciever drier from the jobber, the > seals on it were open, meanign that it was exposed to ambient air, i > contacted everco and they said not to worry as the drier had a rediculous > amount of capacity, like the ability to absorb a pint of water.

Your jobber either lied to you or just doesn't know what he or she is doing. The receiver/drier should be sealed from ambient air. I'd make them take it back and put another one on the car. You can use that opportunity to change the expansion valve at the same time.

Cheers,

C
Reply to
Chris Mauritz
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do the fans work???? if so you may have a stopped up reciever due to the sealer. most often when the h-block goes on a chrysler the low side goes into retard. replace the reciever and re-charge. Chip

Reply to
Chip Stein

Please post your solution once you get there as I have been watching this thread and fighting a similar problem in an 89 Ford van with dual that had been converted to 134a prior to my purhcase. My plans were to replace the reciever/dryer and front orfice tube and evacuate, but left the receiver/dryer in place after fighting trying to get hands and tools into the tiny spaces Ford gives you on the E150 vans. Connected vacuum pump with engine idled (idea being get everything hot under the hood and maybe drive off a little more moisture) for 1 hour and gauges read 30 in vac. Recharged to 35 psi low side,

235 psi high side at about 2000 rpm (took 48oz). Also added seal conditioner. Monitored as adding and also only getting 15 - 20 degrees cooler than ambient.

thanks bb

Reply to
bobby

Not really. It's R134a with a slug of something else to try to move oil back to the compressor.

Not very *well* compatible with either.

Nope, not even close. Nearly identical to R134a.

FR-12 is legal, but I hope your tech properly and legally retrofitted the system, complete with FR12 service ports and FR12 labelling. The problem with ALL refrigerants other than R12 and R134a, regardless of their performance or compatibility, is that none of them is nearly as widely handled and serviced as 12 and 134a. If you have a problem in the future, many shops will charge a very hefty fee or simply refuse to work on your system because it contains a nonstandard refrigerant.

DS

Reply to
Daniel J Stern

I replaced the hoses on my '89 V'ger since they were all leaking oil through the rubber. There was no gas pressure left in the system and barely any oil left in the compressor. While I had everything apart, I also replaced the expansion valve and receiver/dryer.

Brought it to a friend's shop to recharge. I was going to switch to HC134A but was recommended to use "FR-12". Supposedly, this is a new mixture that is more compatible with systems that were designed for R12. The FR-12 is compatible with new OR old oils and has nearly the same pressures and boiling points as R12.

The down side is that while FR-12 costs about the same as HC134A, it is not available to unlicenced techs. Works good though even with the tired old compressor. (couldn't afford to replace it then)

For the OP, if the blower dicsharge was only 15 deg below ambient, was the compressor running full time or cycling? also what was the suction line temperature coming out of the expansion valve and at compressor? If the suction temperature is too low, there may be a blockage of airflow through the evaporator. Also look at the sight glass on the top of the receiver/dryer. should be mostly clear liquid flowing and a few bubbles. More bubbles expected at higher ambient temperatures. Oppie

Reply to
Oppie

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