How do I know AC compressor is working

[Cammy98]

So I finally gave up and want to purchase some refrigerant to recharge the system. Im not too familiar with the AC system however how do I know if the compressor is really working.

I had the car on, turned the AC on full blast and the air is a bit cooler but not roll up your windows and laugh other people sweating.

When I turn on the AC at full blast there is a small reaction from the battery gauge but thats it, should I notice anything else?

[J3$$3]

Re: How do I know AC compressor is working

if you open the hood you should be able to see the compressor engaging when you turn it on and off.

[Cammy98]

Re: How do I know AC compressor is working

Ok ya ran it for a good while and never saw it kick in once.

Does this mean the compressor is dead and needs replacement? or can low refrigerant levels cause it not to run?

[J Phillies]

Re: How do I know AC compressor is working

if the refridgerant is low the compressor will not come on

you can jump it out manually and make the compressor come on to test it ... but i cant really give you instructions on that off the top of my head..


do you have a guage for the 134?

[J Phillies]

Re: How do I know AC compressor is working

also ... just because the compressor does not come on does not mean it is bad ... could be a fuse ... bad relay ... bad clutch on the compressor

[Cammy98]

Re: How do I know AC compressor is working

Awesome thanx. no i dont have gauge.

Yah im going to check the fuses and the relays first, im gunna just put refrigerant in there anyway and get a reading of the pressure. It feels as if it is blowing outside air into the car.

[Brian99]

Re: How do I know AC compressor is working

You need to have the compressor running to add the refridgerant. The compressor needs to "suck" in the refridgerant. When I got my sunfire dd the compressor wasn't running so I took out the relay and cranked the ac on high and jumped the relay using the fuse box and a piece of wire. I wouldn't recommend runing it like that for very long but you need to do that to force the compressor to run to put the refridgerant in.

[Cammy98]

Re: How do I know AC compressor is working

Yah I read about doing that in the manual.

alright sounds like a plan.

[Rob Bell]

Re: How do I know AC compressor is working

You do not need the compressor running to add refrigerant. The pressure in the refrigerant can is higher than the AC system so the refrigerant will flow into the system. It may take a few minutes though. To empty the can quickly turn it upside down. It is OK to do this because the accumulator does not allow liquid refrigerant into the compressor. As the can empties it will get really cold. Also, as the can empties, the pressure in the system will build up enough, so that eventually the compressor will kick on. You will need a gauge to see what the refrigerant charge is, but those come with some of the refrigerant cans anyway. Once the compressor is running, you can get an accurate reading from the gauge. At this point you may need to add a second can. I would also suggest getting a thermometer that you can place into the vents. On my 2002, when the ambient temp is about 80-85, the AC puts out air at the following (approx) temps/fan speeds: Hi=60 degrees, Med=50 degrees, Med/Low=42 degrees, Low 40 degrees. This is when the car is in the shade so the interior is not boiling hot. Once you're getting temps like these, and the pressure at the gauge is good, and the accumulator and cold-side lines have condensation on them, then you have enough refrigerant in there.

One other thing. Before adding refrigerant, use a screwdriver or something and push in (for just a moment) the valve where you will be adding refrigerant. If refrigerant comes out, then the problem is probably a bad front seal on your compressor. What happens is that with age the seal gets weak enough to let some of the refrigerant escape. Once the pressure gets to a lower level, the seal can hold it. Refrigerant with seal conditioner will probably fix this for a while. Eventually though, you will need a new compressor. If no refrigerant comes out, the leak is probably a hole somewhere in the system. This will be confirmed when your AC doesn't work the next day.

[Cammy98]

Re: How do I know AC compressor is working

Alright that sounds even better.

I've had this car for almost 3 years and never put AC into the system but it never blew cold since the first day I bought it.

Well I did press on the valve with a screwdriver and no refrigerant came out. Well im going to buy two cans of the stuff and see what happens.

[Rob Bell]

Re: How do I know AC compressor is working

Get the R134A with the dye in it. That may help you find the leak if there is one. For example, you can put a pan under the evaporator drain and if there is dye in the water, you know the leak is there.

[Cammy98]

Re: How do I know AC compressor is working

Ok so i do have a leak. I didn't get a can with any dye in it but i heard it and felt it.



So I felt the leak in this area, you cant really see it in the picture but I heard it hissing and felt a lot of pressure leaking out. Of course the PSI of the refrigerant fell as well until the hissing stopped. So what can use to seal up this leak because thats a lot of pressure to hold back :eek:

[J Phillies]

Re: How do I know AC compressor is working

i dont think you are likely to have good luck trying to seal that ... better to replace the line

[Blizzard242]

Re: How do I know AC compressor is working

Weld it. It's already broken. Can't ruin it anymore than it is.

[Cammy98]

Re: How do I know AC compressor is working

Hah true, ya i think im just going to solder something on there. It should hold.