Difficulty w/ air conditioner

[Sprung Monkey]

Difficulty w/ air conditioner



Last year the few times I turned the AC on it actually worked blowing coolish air now at over 90* not so much cold air anymore.



After warming the cars AC (cruising around) Iv’e connected the free-on and haven’t observed the AC compressor clutch engage this is when I jump the electrical wires at the warm dryer w/ a paper clip hoping the clutch wound engage well it didn’t and the free-on gauge isn’t sucking any free-on into the sys.



Any tips on recharging the AC. Thanks SM

 

[Mooseman]

From that pic, I can tell you that the system is completely empty. You have a leak somewhere. You were probably already low last year and the rest of the refrigerant probably leaked out.

Now if you jumped the low pressure switch with the A/C on and the compressor didn't engage, then you might have other issues, either electric or the clutch. Check the fuses and try jumping the A/C relay to engage it. If there is power at the relay socket and it still doesn't engage, then go further down the circuit to the clutch and see if power gets there. If it does, then your clutch is likely pooched. With the system empty, it's a good time to replace the compressor (there are no clutch kits available).

 

[JerryIrons]

You can try recharging with a can of UV dye containing refrigerant (NAPA sells it), and then use a UV detecting flashlight at night to see where it's leaking. Probably where a clip holds a line to the frame.

When the ac compressor doesn't engage, I've been known to place the can in a pan of warm water to help it get into the vehicle system faster.

 

[Mektek]

putting the can in a pan of hot water will raise the pressure enough to charge a system that's very low on refrigerant - no need to jumper the AC relay.

 

[JerryIrons]

Yep exactly. If the OP really wants to figure out what's going on he should invest in an AC manifold gauge set for $50 from harbor freight. I am amazed at how many people do not own these who try to fix their own ac. It's not like it's tied to a mfr or model, you know? You can learn a great deal of info from this simple to use tool.

 

[Mooseman]

The idea of jumping the low pressure switch and the relay is to ensure the compressor actually works before trying to add refrigerant. Even if it does, given the system has such a bad leak, that should be investigated after confirming the compressor works.

 

[pell]

Looking at this post to see if it might help me with my problem. The clutch pulls in then drops out with good pressure. Then recently the blower motor stopped, found a burnt out harness at the fan control. Does the A/C work of the fan control?

 

[Mooseman]

No, it doesn't control the compressor directly. The PCM does that. The head unit just tells the PCM that A/C is commanded and it system pressure is good, activates the compressor. Your problem with the burnt harness at the fan controller would affect only the blower fan.

 

[pell]

Ok thanks. Any idea why the clutch would be dropping out with good pressure? Is there a dryer or screen in the system that could be plugged? I ordered new parts for the fan.

 

[Mooseman]

It's a cycling clutch system. If your blower isn't working, it's not taking heat out of the air and the system's pressure gets too low. It will automatically turn off the compressor until the pressure gets back up. This is normal. Once the blower is working normally again, then it should stay on more at idle in warm weather.

That's why it's called a Cycling Clutch Orifice Tube system.

 

[pell]

Waiting on parts, see what happens when fan is working. Thanks

 

[mrrsm]

With the Low Level of R-134A in the A/C System being a separate and distinct issue from the Shorted Blower Motor Harness or having a Burned Out Blower Motor Control Resistor Module-Circuit Board... This additional information can help you if the R-134A Re-Charge will not remain in the system and a more involved HVAC Repair is called for:

How-To Repair Your Air Conditioning

This kind of repair involves more than just an R&R of a damaged compressor, since the old refrigerant must be removed from the system and stored in a proper container. Also... once the new compressor is installed, the system MUST have a near perfect vacuum established or the A/C will not ever...

gmtnation.com

 

[Mike534x]

I had a similar issue with my A/C since I bought the truck, it blew cold up until 80-84 degrees and then it wouldn't blow "ice cold" but just "cool enough". Of course, each time I'd check the freon levels it would be low and take about a half can or so to actually get it back up into the levels it's supposed to be. Almost a month ago the A/C stopped working entirely, the clutch/compressor would not engage and the system had 0 freon. Since I was going out of town, I took it to a nearby shop that diagnosed the condenser was shot with the amount of oil/fluids covering it. They ordered a new one, and now all is well. It gets cold enough that I often need to raise the temp/lower the fan speeds. I was the 3rd owner of a 360 that visited them that week to have the condenser replaced....

Last year my Blower Motor Control Module went up in smoke, driving home from the city and I was experiencing weird voltage fluctuations on the dash. The fans were on the highest speed and with each change in voltage, the fans would "lose" power as if I was messing with the speed setting and then there was a slight burning smell before losing them entirely. Got home, did a search on the site here and pulled the module out to find the connectors were burnt and melted. Replacing it and splicing in the new electrical connector took a few minutes and everything was working again.

 

[JerryIrons]

For one of my ac repairs, I had a condenser that was nearly plugged up. Compressor would start up and kick off, but pressures would measure ok with manifold set. There is however a high pressure cutoff on the compressor, if ac pressure gets too high it turns off. Well on my system guess where the compressor puts compressed freon next, with no way to measure pressure between compressor and condensor? It wasn't completely plugged, wait 30 seconds or so and the freon would flow through! I disconnected the condensor both sides, put some compressed air on the output side and watched as all this grey stuff flew out everywhere from the input side, holy crap! New condenser later and I have nice cold ac in my beater trailblazer. (along with replaced compressor, accumulator and a flushed out system, I had already diagnosed a leaking compressor)

Anyway original poster hasn't replied back, hope he fixed the leak he has somewhere.