A/c Suddenly Went Out

[TCAdkins]

Looked around and didn't see any other forums on this so I made a new one.

My A/C blew good, but was never ice cold which was fine. I just figured it needed a recharge. The it started blowing super cold for a couple nights on my way to and from work. Then on the third day it just wouldn't turn on at all. It doesn't blow on A/C or vent or heat or defrost. I figured a wire disconnected from the dash but I investigated today and found that when I switch it to any of the options listed above you can hear a faint clicking noise coming from the engine bay, passenger side near the firewall. Any ideas? I checked all my fuses and they're good.

Recently put in a new alternator, hopefully that didn't mess anything up.

[onlyinajeep726]

That faint clicking noise you hear is the A/C clutch relay snapping on when you applied power via that slider switch.  My guess is that you've run fairly low in coolant and there's not enough in there now to make the clutch want to come on.  There's an expansion tank with the system's pressure switch that determines when to kick the compressor on.  Have the system charged and see if it begins working again.  If not, then it could be that the pressure switch went bad.  Sounds like you have power every where else that's needed.

[TCAdkins]

I can't get it charged with r12 anymore. How hard is a retrofit?

[onlyinajeep726]

Traditionally, you're supposed to change out the condensor, compressor and core when going to R-134a from what I've been told.  I don't necessarily think that's needed, but you will be better off at the very least getting an O-ring kit and replacing those old ones in each of the lines' fittings.  Then, get it charged to the recommended amount of refrigerant (R-134a in this case, obviously) and you should be golden.  You can also have a shop put in some UV dye to help with leak detection later on down the road in the event your refrigerant gets low again.

 

One thing I forgot to mention previously... Have you verified that the compressor is indeed working?  Like I mentioned before, it sounds as though your A/C clutch relay is working, but do you notice a slight drop in RPM's and/or a slight loss in power when you turn it to A/C?  If not, that would be a pretty good indication that your compressor when out.  Would be a good time to do those O-rings since you'd be disconnecting lines anyway...

[TCAdkins]

I'll look today on my way to the gym.

[Biotex]

Sounds like a leak to me. The clue being that it got colder just before it went out. Evaporators do run colder when low on freon, even to the point of freezing up. Then it quits working due to the low pressure switch which is by design. You don't want the compressor sucking in air which introduces moisture into the system and causes further damage.

 

I would purchase some of the R-12 substitute with a dye in it and get an ultraviolet flashlight. Repair the leak and charge back up. I use an R-12 replacement product that is essentially a propane. Works well enough, and is a bit cheaper. I'll look and see if I can post a link of the product.

 

Edit:

Enviro-SafeTM refrigerant can be used in all R-134a and R-12 Systems. The cans use the same thread and dimensions as the standard R-134a cans. Standard R-134a can taps can be used on this product. To install to an R-12 system you will either need to purchase the Enviro-SafeTM R-134a to R-12 can tap or use an R-12 to R-134a adapter on your low side service port.

 

Note: I used the adapter purchased from NAPA.

 

[TCAdkins]

So it could just be a leak? I hope because that will be a relatively cheap fix. I can retrofit it for r134 and then find the leak with dye and repair it.

[Biotex]

So it could just be a leak? I hope because that will be a relatively cheap fix. I can retrofit it for r134 and then find the leak with dye and repair it.

 

No need to retrofit with R12 replacement. It is compatible. Look for it on Amazon shopping. It is like $9 a can. I bought a case. It has the dye in already.

 

This is just an option, not the only way to do it. You can put 134A in and take your chances. Probably will be fine for many years, no real way to tell.

IMO the refrigerent I post above work as good as 134A.

 

To answer your question, all indications are it is a leak based on your symptoms and my A/C tech experiences.

 

Don't forget you will need an ultraviolet light to see the dye...

[MJCARENA]

You said it doesn't blow air out of any of the vents. Does it work on any of the fan speeds. Sounds more like a blower motor issue then AC isuue. If I read this right.

[Biotex]

You said it doesn't blow air out of any of the vents. Does it work on any of the fan speeds. Sounds more like a blower motor issue then AC isuue. If I read this right.

 

 

Went back and re-read the original post, and you are correct. my brain interpreted "it doesn't blow" as "it doesn't blow cold".

 

Sounds like the fan gave up. Good catch...

[Minuit]

If the fan only works at full speed, it's the resistor. Otherwise, check the connection to the blower motor and the motor itself.

[TCAdkins]

Idk what I did or what happened but when I went to check to see if my rpms dropped or rose the whole system came on and it works perfectly now. Damn older cars. The connection to the blower motor might have rattled loose and then fixed itself. Not sure though entirely.