AC overcharged - compr. shut down?
Thread Starter
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Joined: Aug 2002
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From: Hartsdale, NY
AC overcharged - compr. shut down? If you overcharge your AC system will that cause the compressor to shut down periodically?
My system does this after about 45 minutes of highway driving. When I turn it off for 5 minutes and turn it back on it blows cold again? I assume the compressor clutch stops and the freon is not circulating - not sure yet, however.
There is no place on this board to post AC questions; please write your favorate moderator to suggest a new category for this topic.
Thanks...
My system does this after about 45 minutes of highway driving. When I turn it off for 5 minutes and turn it back on it blows cold again? I assume the compressor clutch stops and the freon is not circulating - not sure yet, however.
There is no place on this board to post AC questions; please write your favorate moderator to suggest a new category for this topic.
Thanks...
If the pressure in the system gets too high, it will shut down...and too much refrigerant will cause high pressure....its bad bad bad for the compressor. Weird that it runs for 45 mins before shutting down though. How much did you put in?
Thread Starter
TECH Veteran
Joined: Aug 2002
Posts: 4,055
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From: Hartsdale, NY
I vacumed the system down with a new pump for 1/2 hour or so and installed two cans of R13.
In the old days, we used to leave the vacume on over night but I assume this is not necessary. Does 1/2 hour sound like it is enough; could this problem be casued by moister in the system that was caused by not leaving the pump on long enough? Is that big shiney aluminum can on top the AC drier? When should the drier be replaced?
What should the high and low side pressures read on the guages when the proper amount of freon is in the system?
Thanks..
In the old days, we used to leave the vacume on over night but I assume this is not necessary. Does 1/2 hour sound like it is enough; could this problem be casued by moister in the system that was caused by not leaving the pump on long enough? Is that big shiney aluminum can on top the AC drier? When should the drier be replaced?
What should the high and low side pressures read on the guages when the proper amount of freon is in the system?
Thanks..
1/2 hour of vacuum should be enough time. That silver canister is the accumulator and yeah it does hold the dessicant (dryer). Usually you're supposed to replace the whole accumulator assembly anytime the system is opened up, but thats overkill IMO. Did you replace any parts of the A/C system while open? Two cans of R134A? How many oz cans were they? Did you add any oil to it? Can't remember the pressures off the top of my head, but I can check.
my ac compressor blew up and i replaced it, the orfice was overlooked and it was clogged with old metal ****. i re did it and fixed the orfice and all was well, btw i use 3 cans of 134a and itll freeze your nuts
J
J
Originally Posted by robertbartsch
I vacumed the system down with a new pump for 1/2 hour or so and installed two cans of R13.
In the old days, we used to leave the vacume on over night but I assume this is not necessary. Does 1/2 hour sound like it is enough; could this problem be casued by moister in the system that was caused by not leaving the pump on long enough? Is that big shiney aluminum can on top the AC drier? When should the drier be replaced?
What should the high and low side pressures read on the guages when the proper amount of freon is in the system?
Thanks..
In the old days, we used to leave the vacume on over night but I assume this is not necessary. Does 1/2 hour sound like it is enough; could this problem be casued by moister in the system that was caused by not leaving the pump on long enough? Is that big shiney aluminum can on top the AC drier? When should the drier be replaced?
What should the high and low side pressures read on the guages when the proper amount of freon is in the system?
Thanks..
Inquiring minds and all. Thread Starter
TECH Veteran
Joined: Aug 2002
Posts: 4,055
Likes: 1
From: Hartsdale, NY
Those are great questions... Thx...
I replaced the head and cam on the motor about a year ago - so I took the raditator and condensor out of the car. The condensor had AC compressor oil in it which drained while it was sitting in the garage. I then reinstalled the unit, vacumed it with a pump for 30 minutes and replaced the freon with two cans (size was 5 inches tall - the ones you see in K-Mart) and one small can of 134A oil.
The vacume was good and it held a full negative reading on my guages for about 20 minutes before the re-charge - so I assume the system is good with no leaks.
If I vacume the system again, should I replace the dryer since it will be the second time the system will have been exposed to the air? Where can I buy a new dryer for a reasonable amount of dough?
Is the orifice tube you are referring to called the "sight glass"? Where is this located?
Where is the pressure switch and how do you check it?
I replaced the head and cam on the motor about a year ago - so I took the raditator and condensor out of the car. The condensor had AC compressor oil in it which drained while it was sitting in the garage. I then reinstalled the unit, vacumed it with a pump for 30 minutes and replaced the freon with two cans (size was 5 inches tall - the ones you see in K-Mart) and one small can of 134A oil.
The vacume was good and it held a full negative reading on my guages for about 20 minutes before the re-charge - so I assume the system is good with no leaks.
If I vacume the system again, should I replace the dryer since it will be the second time the system will have been exposed to the air? Where can I buy a new dryer for a reasonable amount of dough?
Is the orifice tube you are referring to called the "sight glass"? Where is this located?
Where is the pressure switch and how do you check it?
