A/C revalation

Well I scoured the search engine and google for all the info I could for Doing my own A/C charge and got the guts up to do it. Went cheapo w/Autozone low pressure only kit and couldn't figure out what was taking so long. I had the selecter on recirculate and full fan and following directions turned can from 12 o'clock to 3 o'clock and shook the can for like an hour! Clutch kept turning on and off constantly and no cold air. Finally re-checked the valve and opened it up a little more and presto! I feel like and idiot! Pressure went in range and I turned can over for about a minute to let oil/additives in and now compressor stays on and its super cool!
I will really appreciate that for the camping trip to California!
Thanks everyone for all the great threads and giving me the courage to not give up hope. Wasn't really that hard once the valve was open all the way!
:clap:

I thought turning the can upside down was a bad idea?

I wish whatever was wrong with my A/C was that simple.

Thats great, but if your air was low on refrigerant than you probably have a leak, so try it for a couple of weeks and see if it holds a charge. And also, putting too much of the oil and additives(the refill kits at parts stores) into your system is not always a good thing. Not trying to discourage you, just being honest. Just hope you dont have an evaporator leak!!

Thanks as I am a newbie to the A/C thing. Just following directions on kit. The R134a I bought was not the kind with "stop leak" or "additives" as far as the label could tell. I bought the car knowing it had been evac'd by a shop for heater core repair. Hopefully no leaks (at least holding out for the Cali trip)!
I'll check this morning if still cold and go for it. (Leaving today either way).

Good info. So was your AC cycling on and off even on Max AC? What year XJ?

On my '96 XJ the AC Compressor kicks on and off and on and off even when the Max AC (recirculate) selection ... so I may be low on coolant.

I've got the gauges and am just to ignorant to figure out what my pressures are suppose to be and all that. I'm afraid to fry my compressor.

Did you take any pics? Any more details is appreciated.

redsnake start with 1 can it will probably put you in the ballpark you dont ness. need gauges when my 98 gets to the on off on off point 1 can gets me going and id rather put 3 or 4 cans in during the summer rather than tear the dash apart i only drive like 2or 3 k. a year ( over the road truckdriver) and the few days i get off a month dont want to spend working on jeep

Redsnake said:

Good info. So was your AC cycling on and off even on Max AC? What year XJ?

On my '96 XJ the AC Compressor kicks on and off and on and off even when the Max AC (recirculate) selection ... so I may be low on coolant.

I've got the gauges and am just to ignorant to figure out what my pressures are suppose to be and all that. I'm afraid to fry my compressor.

Did you take any pics? Any more details is appreciated.

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The cycling even on max is normal. Should be less than about 10x a minute, though.

According to my 98 FSM, 5 times a minute on the cycling. I need an evaporator.:doh:

You don't want the AC on max while adding refrigerant. It is best to have the blower on high with the AC on normal which brings in hot humid (unless your in Arizona) outside air to put a higher load on the AC. The higher load reduces cycling and allows a faster refrigerant charge time.

By the book one should not invert the refrigerant add can as it can introduce a slug of liquid refrigerant which can damage the compressor. :shiver:

That being said I have noticed in my jeeps that reed valves in the low pressure connector side seem to act as an expansion valve, restriction, that limits liquid flow rate especially if there is oil in the add can and it seems to protect the compressor from slugs of liquid refrigerant, at least when there is oil in the fill/ad can of refrigerant.

I found it neccesary to invert my refrigerant add can before the refrigerant in the can was all added to the system, but for a few seconds at a time only, to get the oil out of the can and into the system. It is not the best way to add oil and not the safest way for the compressor either.

Down here in Houston, at 100 F, 100 % humidity, my Jeep ACs almost never cycle off even on Max AC, which does not allow any outside air into the cabin. On AC Normal (allows outside air in) mine never cycle off in the summer.

Up north in cooler weather, or hot less humid weather, in other words smaller heat loads, some cycling may be normal, but I would not expect 5 cycles a minute to ever be normal. If it cycles that much the AC does not need to on in the first place, IMHO. IF it cycles more than once every two minutes it needs to be switch to normal AC or turned of, or it needs repair work IMHO.

Frequent Cycling is not good for the clutch over time. If it is hot and humid and the compressor is cycling I would look for a leak and low refrigerant. Otherwise I would look for a clogged expansion valve, or too much refrigerant, overfilled, triping the high pressure cut out switch, or a clogged filter dryer, or a defective LPCO or HPCO switch or thermal sensor.

Turning can upside down forces liquid "freon" into system. I usually carefully do it that way on the first can, DO NOT let the compressor lock up! as liquid not gas is flowing! Warming a can in hot water also speeds up charging. >>>DO ANY OF THESE AT YOUR OWN RISK<<< If you know nothing about AC, DO NOT EVEN THINK OF CHARGING YOUR OWN AC SYSTEM! >>>R12, R22, R134a or any other REFRIDGERANT will instantly freeze your skin! I won't EVEN warn about fire and "freon".

Fire and Freon warning?

Freon was once used as a fire extinguishing agent in fire extenguishers and computer fire supression systems.

badgator said:

Turning can upside down forces liquid "freon" into system. I usually carefully do it that way on the first can, DO NOT let the compressor lock up! as liquid not gas is flowing! Warming a can in hot water also speeds up charging. >>>DO ANY OF THESE AT YOUR OWN RISK<<< If you know nothing about AC, DO NOT EVEN THINK OF CHARGING YOUR OWN AC SYSTEM! >>>R12, R22, R134a or any other REFRIDGERANT will instantly freeze your skin! I won't EVEN warn about fire and "freon".

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Can anybody diagnose this?

My A/C seems to work for awhile, then the chilling diminishes and such to the point where it doesn't seem to be very cool anymore.

Also the HValve will whine and the compressor kicks off, randomly. Any ideas?

Ecomike said:

Fire and Freon warning?

Freon was once used as a fire extinguishing agent in fire extenguishers and computer fire supression systems.

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Not sure about R134 or R12, but freon and the halons are somewhat similar. The issue is that heating freon or exposing it to flame creates some really nasty poisonous stuff like phosgene gas. Not real friendly. Also some of the R12 replacements contain high percentages of butane and propane (one out there is a straight mix of the two).

lawsoncl said:

Not sure about R134 or R12, but freon and the halons are somewhat similar. The issue is that heating freon or exposing it to flame creates some really nasty poisonous stuff like phosgene gas. Not real friendly. Also some of the R12 replacements contain high percentages of butane and propane (one out there is a straight mix of the two).

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Freon is a halon. Freon is the original Trademark name for R-12 (and the Freon family which inluded R-22, and ?) that Dupont Registered at the US PTO many moons ago. I am pretty sure they are still in limited use as fire extinguishing agents for special applications. If you get them hot enough, like over 800 F they will thermally decompose, but they will not support a fire or burn in and of themselves. They were heavy, dense enough to choke off the oxygen supply to a fire. They had advantages over water in electrical and fuel (liquid fuel) fires.

Yes, phosgene (WWI Mustard gas, as I recall, lovely stuff) is or can be a by product of incomplete combustion of the halons, but many household materials generate phosgene gas during incomplete combustion as well. I had some hands on experience with phosgene from a leaking 1,1,1, trichloroethane vapor degreaser that was leaking into the gas burner tube that heated it from the bottom many moons ago. Very corrosive stuff along with its other unpleasant features.

He, and I only mentioned R-12 and R-134a. Yes, there is other stuff (I will call it stuff for now), other blended refrigerants out there that contain highly flammable components that I would avoid like the BB plague.

One of the biggest problems with those blended refrigerants is no one has the proper recycling equiment to recover them.

Hvalve???

Blaine B. said:

Can anybody diagnose this?

My A/C seems to work for awhile, then the chilling diminishes and such to the point where it doesn't seem to be very cool anymore.

Also the HValve will whine and the compressor kicks off, randomly. Any ideas?

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