Hello all, I have a problem with my ac and is looking for some help/guidance. My ac worked fine for almost a year and suddenly my compressor froze up. I did not know that that was the problem at the time as I took it into the local shop because I had a burning smell comming from the hood. They said the ac compressor froze up and the belt was burning off. They repaired it for about $485.

I did not use the ac as this happen over winter. Come summer I tried to use the ac and hot air was comming out the vents. i took it back to the shop and they say the USED compressor thay put in was turning but not doing its job as a compressor, I ask how much to fixed it, I grabbed my keys and left in a hurry when they said $1200 in order for them to guarantee the work.

I decided to do the job myself and this is where i need some help. I took the sytem apart and while flushing the condensor, big chunks of metal pieces came out, this tells me that the crap shop just put the used compressor on the car, did not change or flush anything and slid me a high bill.

I flushed the evaporator and condensor till no metal pieces was present and took all the ac lines out and flushed them individually. I changed the expansion valve and receiver/drier and got a used compressor under warranty, put new pag 150 oil in the compressor as I have a 1996 sebring convertible, and this is the recommended oil.

I put the system back together with new orings and connected the receiver/drier last as not to get air/moisture in it. I also put uv die in the suction side of the compressor for leak detection and put the system back together.

I then evacuated the sytem with a Vacuum Pump pulling at 30 psi for about 2 hrs (i fell asleep ) and then close the valves to the high and low side, shut the vacuum pump off and let it sit for 30 minutes. When i returned, it was still at 30 psi so i rotated the compressor clutch so the oil will lubricate it and open the low side and added a can of refriderant (134a), started the car set the blower to high, turn ac switch on, compressor clutch kicks on and I continued to add the required refriderant.

The thing is, the clutch engages, i see no leaks, the receiver/drier and expansion valve is new but am still at 90 degress comming out the vents. Is this the sign of a bad compressor, i need to know because I can return the compressor which is what am about to do and just get a new unit.

Sorry for the long post but I wanted to let you guys know what i did or what needed to be done that I did not do, things i can check to ensure i have a bad compressor or expansion valve.

Any help and or suggestion would be really appreciated.

Thanks
Matrix733

 

Use the manifold set to check the low and high side pressures while the car/ac is running. Then post back up here.

 

also might want to know how much refrigerent you have added did you fill it up to the specs or only add 1 can, along with pressure readings should help to figure out whats wrong.

 

low side pressure when blower set to max ac clutch engaged is 40 and 250 on the high side. The high side actually was around 150 but I added more refriderant as it was at thirty.

There is a problem here as the suction line from the evaporator to the compressor is not cold.

I added 2 1/2 cans or 1.75 lbs of refridgerant to the system and 7 oz of oil.

Thanks.

Matrix733

 

what does the sticker under the hood say the system calls for and is the cooling fan working when the a/c is on?
was the readings took at idle speed?
the pressures dont really indicate any problem with the compressor would probably suspect an expansion valve problem if the line isnt cool near the expansion valve and it is full or very close to full of freon and the fan works.

 

Any chance your temperature blend door is broke? If you turn the temp control in the car from hot to cold do you hear the actuator moving the door? Could be everything is working fine on the AC end...but the air isn't flowing over the evaporator...it's flowing over the heater core instead.

 

am stumped, i can only blame the compressor now. I changed drier and expansion valve again, check oil in compressor and add the required amount (7oz), added uv die and evacuated system. no leaks found. added 1.75 lbs of refridgerant according to the label under the hood.

ac turn on blower turn to max, pressure on low side 45 psi and 270 on high side. Line from evaporator to compressor is still not cold. the high side line is hot as it should be. the vent door in car is open, i took it apart and manually open it to make sure it changes between hot and cold.

my friend as the same car so he took it over and his pressure is 45 on the low side as well but his line from the evaporator to compressor is cold almost the instant he turns the ac switch on.

Am wanting to blame the compressor because even though i hear an hissing sound when it engages, I had to rotate it manually about 10 times before i charged the system to ensure the oil circulation but when i did this the clutch spun freely as if there is no compression/suction, it should be almost hard to just turn with one finger, right.

Anymore ideas is just welcome.
Am about to just get a new compressor but let me get this right, I was blaming the expansion valve since the line from the evoporator to compressor is hot but what if the compressor is not doing its job, what about the evaporator, is it just a coil just like the condensor?

Thanks
Matrix733

 

the compressor is just a pump basicly if its doing its job the pressures will be normal if its not doing its job the pressures will be low on the high side and usually high on the low side at idle speed.
im assuming the cooling fan is working but you never stated it is I would expect the high side to be alot higher if it wasnt.
some do turn hard some turn very easily not really an indicator of a bad compressor.
so how much oil is in the system now 14 oz did you add 7 more and why would you need to check the oil again?

 

What do the pressures do upon engine accelleration? I'm thinking your expansion valve is stuck open.

 

feel the evaperator? is it cold? if not, Ive got to think that there is something wrong with your expansion valve. Are you sure that you installed it correctly?

 

Theb condenser should be Hot ,,,

seems the compresor is Ok due to the readings

 

after 2 driers, 2 expansion valves, 3 flushes, evacuation and refill,
(about $650 later the son of a ***** decided to work, hahahahaha, at
least all that work was not in vain.


here goes, I reflushed the condensor this time with the hoses still
attached to the condensor. I flushed it with more pressure in reversed
of what i did before for eg, I attached the air hose to the smaller
line after filling the condensor with mineral spirits. To my surprise
a big chuck of metal came out that could not pass through the other
side since the line was smaller.


I then removed the compressor and drained it completely and hook my
airline to the suction side and as i blow the oil out the clutch
activated as a result of the pressure so it got emptied pretty good.


Put it back together and no leaks, charge it up and let it sit
overnight after running it for about 30 minutes, it did not work at
this point. Started it in the morning and the pressures were back to
normal and the line from the evaporator to compressor was cold and
started perspiring, lol.


I now had cold air in the cabin, now on to installing the wifes remote
start and power locks in her corolla, damn it, lol


Thanks for all your help


matrix733