AC Line Blew A Leak

Other day I was starting my truck and heard a loud pop off and hissing sound, like an air compressor tank purging out. I shut it off and the sound continued for about 10 seconds or so, kicking up a bunch of dust under the truck. I smelled what I thought might be freon, so I popped the hood and gave whatever AC lines I could see a look-over and couldn't see anything out of the ordinary. Started it up again and no sound, and I could feel my AC getting cold so I just put it off at the time.

Over the last couple days it seemed like the AC wasn't getting as cold as it used to. Kind of hard to gauge because we've shot up around 120 here in AZ, but I noticed even at night the air was barely cold by the time it reached your face.

I read that freon can glow with a black light, so I spent about half an hour combing around the engine bay finding nothing. Was about to give up when I caught a glimpse of the top side of the belly pan and noticed what looked like spray and was glowing green. I got underneath the truck, removed the pan and saw green splotches glowing all over it. Couldn't get up in there high enough to actually see where it might be coming from, though.

Anyone else encounter anything like this, or has replaced the AC compressor and knows the best way to access it? I'm going to take a look at it tomorrow when I have some light, now that I know whereabouts it's coming from.

 

The refrigerant itself is a gas, doesn't glow or leave any kind of residue. But the AC lines also have compressor oil running through them, which is usually the telltale radioactive green that you describe. Try to isolate where it came from, based on where the big splotch is in relation to the lines. Could be a bad fitting/seal, a chafed line, or even a small pinhole.

The compressor is probably fine but will eat itself if you run it, now that so much oil is blown out of the line. Plus any air or moisture that may have gotten in. So whatever you do, don't run the AC or try to recharge it at this point. Pull the fuse/relay until you can get it looked at.

Whether or not you're able to find the leak, you'll have to take it to a shop and have it drained before you work on it. There could still be pressurized refrigerant in there, which is highly toxic and super bad for the environment. And after a line is opened up, you'll need to get the system vacuum purged to suck all the air out before they refill it.

PS- sorry to nitpick, but calling it Freon is a pet peeve of mine lol. Freon was a suuuper toxic refrigerant used decades ago and has long been phased out. R134a is used nowadays. Still very toxic but not as bad.

 

Maybe...?

https://www.tacomaworld.com/threads/air-compressor-explosion.664720/#post-23296210

 

Suggest professional help here.

More knowledge, skills and tools will be required for a proper fix. Especially since the system has been exposed to atmosphere.

Also suggest not to wait. The longer it's open, the more risk of other damage from moisture.

And do not run the system

 

Well good thing this happened in the summer...in Arizona. Jk, OP.

Take it to a professional. They have the proper equipment. Hopefully it's something easy and cheap.

Also, don't run your AC, as others have said.

 

Update:

With some light I was able to find pretty direct access to the compressor through one of the windows next to the driver side shock tower. Inspected all the lines for damage or signs of leakage around the connections and found nothing. Hooked up some gauges and the system is holding pressure fine.

The best I can tell, this shot off directly from the back of the compressor itself, leading me to believe it was the high pressure valve purging out a spike in the pressure. Going to have the system recharged and report back with whether it leaks anything and if the AC gets colder (still blowing cold but not enough to really bring the cab to a comfortable level.)

 

That's pretty wild. Never heard of freon purging from the compressor before. But I don't really know anything about AC systems.

At idle my AC will blow around ~60* in this heat. On the freeway it's ~34*, just for some baseline / reference.

 

My last truck I replaced the condenser and I had Sears do the purge and recharge and they did a great job for $139 .