I was told to replace the air compressor on my

the system has to have enough Freon to produce pressures to properly check for leaks. the entire system needs to be checked, lines, Schrader valves, condenser, all fittings, evaporator, compressor seals. there is a leak it just has not been found.

If the ac compressor is running and the line is cold, it could be a blend door under the dash that is not cutting off air flow thru the heater.

that depends on what happened to the last one.
if the last one , broke up inside it then contaminates the whole system, insuring the new compressors early death.
at the least, a compressor, receiver /dryer. (my be the expansion valve)
1: must be done in a shop, so they can capture the old freon.
ie: Ozone damage, ever heard of that?
2: then replace all bad parts.
3: next, pull a hard vacuum on the system (removes all water)
4: adds freon by weight.
5: test system for full performance and correct any deficiences.

There is a valve that stops hot coolant from entering the heater box. It is probably stuck open. murf427

Had the same problem on my 2004 Jetta this summer. First check if it's low on freon If the clutch kicks on and off it needs a charge. Suct
press should be about 40-45psi. If you have the correct charge and the compressor clutch does not click when you turn switch on,the clutch is bad. I found it easier to change the whole compressor than just the clutch which requires special tools. You need to install a new filter drier also before recharging. Before I would spend $400 on a new compr I went to a local pick & pull and got one for $15 with a 30 day warranty. Doing the work myself including Freon, new compr oil, the filter which I got on-line from RockAuto.com
and the used compressor it came to a whopping $90. If you have a repair manual, follow the instructions carefully and do your own repairs you can do this. If not, it's still cheaper buying your own parts and paying someone to do it. You can also google instructions. I'm 81 yrs young and if I can do this anyone can. I hope this helped.

Check to see if the clutch on the A/C compressor is turning with A/C on max. If not then the clutch is bad or a fuse blown. Check Freon level or have a shop do a leak test. If you replace the compressor always replace the dryer as well

The compressor on the air conditioner in my 2000 GMC Yukon XL went out last summer. Had it and the whole line replaced at a local air conditioning shop last fall. Used it little before cold weather. Warm weather this spring and no cold air. We could hear the compressor trying to kick in. The shop told us that the control console was bad and had to be replaced. They told us the part was on back order and did not know if they would be abel to get one any time soon. We took the Yukon into the local GM dealership. They told us that the high side fitting was bad and that the freon was very low and that they would have to deal with that first to check the system. Called back to the air conditioning shop and they said they had a console come in and they would put it in and check the high side fitting. I now have cold air and questions. Bought Yukon in 2005 used, had always had problem of not switching to cold air once the heater has been used. We were told changing the console should fix that. It has not changed. I feel like the console angle was a scam, that the system was just low on freon. Each shop was blaming the other for trying to scam me. And what can fix the heat to cold issue? If anyone has answers I would sure appreciate the knowledge.

Air compressors very seldom become defective. However, if you wish to tackle the job make sure the freon is removed from the unit by loosening the high pressure valve. I would suggest you take it to a shop and have it repaired. Purchase what ever you need from the internet. Purchased all the parts to redo my 1966 mercury from Ebay, saved $400 hired expert to do the job for $200. Tools for replacing are expensive you would come out better by having it done. May be a small problem, such as the dryer, or low freon, or a leak Most shops will diagnosis the problem for free or a small charge. Or you could check the unit by adding a leak detector using the low side of the air condition unit. The low side is the lareer of th two lines in the unit.

Sounds like you lost your refrigerant in the system, couple options here, 1. Take the chance its a very slow leak and just recharge it or have it recharged, sometimes vehicles will last all summer or even more, but keep in mind, if large leak you just wasted some money charging the system. 2. If it was mine, most repair shops can send a dye through the system and pinpoint where losing freon. Losing freon is the most common A/C failure and keep in mind can get costly if not fixed right.
3. Last but not least is the compressor, not as common of a problem as losing freon but still could be the problem, this is where taking it in somewhere that deals with air conditioning on a regular basis could troubleshoot this easily, but hopefully the compressor is not at fault as they usually run $200 or more.

1. check your fan belt, if your fan belt is in the normal position and no problem.
2. check your compressor and also check the clutch, it is locate right in front of the compressor, when you turn on your air conidition, the clutch should be turn with the fan belt. If it is not, that means your compressor had problem.
3. check fuse.
4. check the freon small flow window see if the lique bubbling too much, if it is means you need fill up R-12 freon.
5. you probably can not do it yourself, in case if you need freon and your compressor is completely empety, you need a special tool to **** the air out first and than fill up freon.
6. if your air condition is leaking,and you have to fill up a can of special check leaking freon with red colour first, until you find the leaking parts, fix it then you can fill up freon