A/C Issue

[ibrokeit]

On my 1993 F250. I was told the compressor was newish when I got the truck. A/C has never worked. System wasn't charged so I charged it. It charged really fast (maybe 1/4 of one of the big autozone cans?) and seemed to hold pressure but the compressor still didnt kick on. Jumped the compressor and it ran, but still no cold air. What to check next?

[ibrokeit]

Anybody?

[jamesrw30]

Did the little hamster get tired? Some times they need a vacation.

[ibrokeit]

I wish I knew. The tacoma is costing me too much in little random parts to keep it so road worthy. I wanna start splitting DD time between the taco and the F250

[Horton]

if it was dry and you put 1 can in it will more......they have a low pressure switch so if the freon is low it wont kick on

[ibrokeit]

if it was dry and you put 1 can in it will more......they have a low pressure switch so if the freon is low it wont kick on


I was reading 0 psi. It didnt even take half of a can before it read 45 psi (or whatever full is). Not nearly enough. I just dont know why.

[Horton]

if it read 0 then you didnt pull a vacuum on it...right?.....its full of air...which is not good

[Yotabomb01]

f250 usually use 1.89 to 2.33 pounds of freon. so 16 oz to lbs and one of those bottles usually range from 12 to 16 oz. Taking that it was a 16oz put another 12oz in her and see what it does. most of the time the low pressure switch wont let the compressor kick on when its 30% below charge! If the system was empty id say it has a leak. You would be better off taking to a shop to let them pull a vac on the system so your not wasting your time or money, but if you are wanting to do it yourself get a can of dupont 134a from oreillys with UV Dye in it so that you can tell if its leaking if it goes out in the next few days from charging it. You will need a pair of yellow glasses and a black light to see the "bright green" showing from where it "may" be leaking. Hope it helps. If you need some help along the way just give me a call, 276-870-1604 My name is KR. Im ASE Certified in A/C.

[Rtaylor]

You can go online and buy a vacuum pump for $89 and a set of R134A hoses for another $59. This cost about the same as paying the local mechanic to vacuum down the system.

If the system has air in it when you charge it you will have problems. Acids will form in the oil which will damage the compressor, and your pressures will not be right. The best way to know that you get it right is to pull a vacuum on it and start from the beginning.

Like yotabomb01 said use the dye and find the leak. Replace the bad o-ring or leaking component and then vacuum the system down to at least 28" of mercury. Break the vacuum with refrigerant and then pull another vacuum on it. After you are satisfied that the system is not leaking, charge the system with around two twelve ounce cans of R134A.

Add refrigerant until the low pressure gage should be set to about 35PSI (this corresponds to a 40 degree coil temperature). The head pressure will vary depending on the outside ambient air temperature. Typically it will be below 225PSI. If your pressures are not close to this then you have other problems and will probably need to get professional help.

[ibrokeit]

if it read 0 then you didnt pull a vacuum on it...right?.....its full of air...which is not good

No, I didn't.


You can go online and buy a vacuum pump for $89 and a set of R134A hoses for another $59. This cost about the same as paying the local mechanic to vacuum down the system.

If the system has air in it when you charge it you will have problems. Acids will form in the oil which will damage the compressor, and your pressures will not be right. The best way to know that you get it right is to pull a vacuum on it and start from the beginning.

Like yotabomb01 said use the dye and find the leak. Replace the bad o-ring or leaking component and then vacuum the system down to at least 28" of mercury. Break the vacuum with refrigerant and then pull another vacuum on it. After you are satisfied that the system is not leaking, charge the system with around two twelve ounce cans of R134A.

Add refrigerant until the low pressure gage should be set to about 35PSI (this corresponds to a 40 degree coil temperature). The head pressure will vary depending on the outside ambient air temperature. Typically it will be below 225PSI. If your pressures are not close to this then you have other problems and will probably need to get professional help.

Thanks. More than I can afford to spend at the moment so looks like it will just sit until it gets warm next spring.

[Want2Wheel]

Remember that defrosting the windshield also uses the AC. If you were closer I would be glad to pull it down for you. Rob

[pplblazerdude]

Just unplug your compressor so it will not do damage if you use the defrost. I lost one from this one time. Expensive mistake.

[Jazzman31]

If the compressor did not kick on when you were adding the can of freon, then you did not add any to the system. I have a slow leak in my jeep and if the compressor does not kick on I have to manually kick it on to pull the freon out of the can.

[Rtaylor]

If the compressor did not kick on when you were adding the can of freon, then you did not add any to the system. I have a slow leak in my jeep and if the compressor does not kick on I have to manually kick it on to pull the freon out of the can.

Just put the can in a pot of very hot water and all the freon will go into the AC system where the pressure is lower...

[Horton]

if you would like i can PM you my ph# and tell you how to do it the "redneck shadetree way"...its easy and cheap

[ibrokeit]

If the compressor did not kick on when you were adding the can of freon, then you did not add any to the system. I have a slow leak in my jeep and if the compressor does not kick on I have to manually kick it on to pull the freon out of the can.


The compressor did not come on but it went from showing 0psi to 30psi. I jumped the compressor to make it come on. Pressure stayed at 30psi and no cold air.


(I think it was 30psi...whatever the can said was the recommended pressure).

[Jazzman31]

Does the compressor come on by itself now when you turn the A/C on?
If not then you probably still do not have enough pressure in the system or the pressure switch is bad.
I am thinking that even though you have 30lbs of pressure, it could be, something is clogged in the input or output part of the compressor.
I can manually kick my compressor on but unless it has enough pressure and freon, it will not kick on by itself.
I think you may need to go and see WanttoWheel (Rob) and let him pull it down for you.
The previous owner might of put too much leak seal in it and clogged the system. Too much will gum the system and the only way to know for sure is if you can pull the system down and see if it can be pulled down.
I used one can it didnt solve my problem so I just recharge once a year.

[ibrokeit]

Does the compressor come on by itself now when you turn the A/C on?
If not then you probably still do not have enough pressure in the system or the pressure switch is bad.
I am thinking that even though you have 30lbs of pressure, it could be, something is clogged in the input or output part of the compressor.
I can manually kick my compressor on but unless it has enough pressure and freon, it will not kick on by itself.
I think you may need to go and see WanttoWheel (Rob) and let him pull it down for you.
The previous owner might of put too much leak seal in it and clogged the system. Too much will gum the system and the only way to know for sure is if you can pull the system down and see if it can be pulled down.
I used one can it didnt solve my problem so I just recharge once a year.


Compressor still doesn't come on by itself. I would go see wanttowheel, but for the fuel it would cost me, I'd just buy another truck.

:icon_mrgreen:

[Want2Wheel]

I would start taking the system apart, and looking through lines. Replace orings while you are at it. Check and make sure that the pressuer switch is working correctly. Check wiring with VOM, and test light. The AC system is pretty simple, we should be able to figure out what is going on. Get someone to pull a Vac. on the system and see if it will hold it, and then go from there. Rob