How do I figure wether Bad/ Good Compressor on AC

[JAG1]

Before hot weather arrives I would like to be able to diagnose my A/C system on my 2001.. When on only puts out ambient outside air temperature no cooler air at all.

 

How to check/ troubleshoot.

[Killer223]

you need some gauges first,

Is the compressor clutch kicking on?

is it an airflow issues through the condenser?

all the blend doors work as they should?

 

[JAG1]

Blend doors work as they should.

I will check on the compressor kicking in and condenser clogged.

 

Just need to go thru process of elimination with the simple obvious items before I pay someone if you guys can help with that.

Thank you.

 

Update; I can hear the compressor kicking on with the 2002 truck but it does not kick on with the 2001 truck. Handy to have trucks to compare... so I should be looking at a relay perhaps?

Edited April 30, 2017 by JAG1
Update...

[notlimah]

I'm subbing to this. I think my A/C is pretty much non-existent. I don't mind as I usually just have the windows down, but with the wife and little one, it's preferable.

[JAG1]

I think most common problem is the leaks. I'm looking for the relay... next project test for 12 volts. Or should have what batteries are showing.

[TFaoro]

If the system is empty, it won't allow the clutch to kick on (keeps from destroying the pump)

I would get a gauge or at least one of those "fill up" bottles with a gauge so you can see if there's any R134a in it. 

[JAG1]

good advice Tyler, thank you.

[CSM]

A set of harbor freight lines, a can of refrigerant, and a loaner vac pump from an auto parts store is pretty easy.  

 

The rest of the troubleshooting can be easy or complcated.  My clutch died, but a new pump and r134a and its been solid since.  

[IBMobile]

JAG, this may help you diagnose the A/C problem.

 

[JAG1]

Tthank you for the link IBM. Before I got the link I recharged the system after finding the compressor was indeed working... I was looking behind the belt pully and you have to look at the front to see when the clutch engages.

Brought the recharge up to the correct range for the ambient temps. Went in the truck and now I have cold air.

I can only hope I don't cause damage to the system after reading IBM's link.

 

I wish now that I brought it to an A/C shop instead

IBM, should I just not use the system till I get it checked out?

Thanks..

 

Edited May 1, 2017 by JAG1

[IBMobile]

Was the A/C compressor clutch cycling on and off before adding 134A and if so how quickly was it doing it, the shorter the on/off cycle time the lower the amount of refrigerant in the system.  How much 134a did you add? 

 

If the A/C clutch is staying engaged and the accumulator is cold with a duct temp of 34°-40° I'd call it good.  

 

 

[TFaoro]

2 minutes ago, IBMobile said:

Was the A/C compressor clutch cycling on and off before adding 134A and if so how quickly was it doing it, the shorter the on/off cycle time the lower the amount of refrigerant in the system.  How much 134a did you add? 

 

If the A/C clutch is staying engaged and the accumulator is cold with a duct temp of 34°-40° I'd call it good.  

 

 

He said it wasn't cycling at all before (3rd post) 

When I had mine done professionally it was blowing 23* on a 70* evening. I also had a new condenser and evaporator though. 

[IBMobile]

2 hours ago, JAG1 said:

I was looking behind the belt pully and you have to look at the front to see when the clutch engages.

So we'll never know if it was or not.

 

If the duct temp goes below 32° there is a chance of the evaporator freezing and causing a blockage in the system.

 One type of thermometer can give a different reading than another.  I've used a non contact thermometer to measure duct temps and have see readings change within seconds of each other with duct temps in the twenties and teens.  A  basic analog thermometer reacts slower and I've never seen a duct temp below 32° with one.   

[JAG1]

I must explain.... The clutch was cycling fairly rapid when I began filling. It was cycling about every 5 seconds or less more like every 3 seconds.

I put in till it read that I had about 200 lbs., about half the can of a 22 oz. can. I tried to add more to get it to go to the top of the range for my ambient temperature but it would go back down and stay at around 200 lbs and quit filling at that point which was in the middle for 67 degrees farenheit ambient.

 

Earlier I had said that the clutch was not cycling but was wrong because I was looking at the back of the pulley and not the front.

Getting older sucks...

 

Thank you all for helping... tell me if It would be okay to use the system based on this update.

 

 

Edited May 1, 2017 by JAG1

[pepsi71ocean]

IMO, when charging the AC system, it is best to blow it down, and pull a good vacuum on it, and charge it back up with a new charge of oil added to it.

 

When properly charged i stop when i can run the motor at +/- 2,300 rpm's, with the compressor NOT cycling, but staying on. Provided you don't have a leak you should be good, if you do have one and it is small then just add a can of straight Freon here and there, but after about 7 or 8 cans it is best to pull it down and replace your compressor oil again.

 

What i find is you want to keep your low side around 32/35psi and your evaporator should stay above freezing.

 

The compressor, and manifold gauge and t tap was about $250 total, well worth the effort if your mechanically inclined.

[Mopar1973Man]

Like my compressor is fine for A/C performance but @IBMobile mention in a previous post my belt squeak is a clutch assembly issue. So this week I'm going to be shopping for a new A/C compressor to replace this one because with hot weather coming and the belt squeak problem I don't need any failures on the truck. 

[JAG1]

1 hour ago, Mopar1973Man said:

Like my compressor is fine for A/C performance but @IBMobile mention in a previous post my belt squeak is a clutch assembly issue. So this week I'm going to be shopping for a new A/C compressor to replace this one because with hot weather coming and the belt squeak problem I don't need any failures on the truck. 

Yes.. and the new girlfriend needs to be taken care of too by keeping her comfortable.

 

With a gal like that your going to need air temp blowing at about -10 degrees F.