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house airconditioning pipe insulation smells like burning truck brakes? Answered

I smelled "burning rubber" in my garage; noticed that rubberized insulation on pipes leading outside to the a/c compressor was worn, aged, and peeling. (20 yr old pipes) Question: Does a/c pipes get hot, causing enough heat to melt insulation? The pipes run thru the exterior wall, up and into the garage, to the central air unit. Is the insulation only outside, or the entire length of pipes? Is this repairable or should I call an expert (that will probably charge me an arm and a leg!!) What type of fix-it material do I buy? Can I get this at Home Depot or Lowe's? Why am I smelling it in the first place and where is the smell coming from?? Can this cause a fire!! Thanks.


Get out and feel the pipes ! (carefully), yes, AC pipes can get MIGHTY hot. Its possible you may have a coolant leak too, but I am not an AC expert, I've noticed it with refrigeration systems I have built at work.

Soooo...if it's a coolant leak, that "burnin' truck brakes" smell is the coolant leaking? I'm assuming the leaking (which is hot) melts the insulation, which is what I smell...melting insulation & rubber. Is that correct? Thanks for your help!

Probably. I'd get a technician in to check your coolant pressure, but I am not, repeat not and AC engineer ! Steve

I'm not sure where the smell is coming from. But the insulation on the coolant lines will start to deteriorate after several years and can be completely gone in a decade. Do you live where the sun shines on the pipe. Like Texas or Florida? You can reinsulate the pipes where you can get to them with insulation sold at the hardware store.

I live in sunny & HOT Sacramento, CA. and yes, the exterior pipes running from the compressor into the house are in direct sunlight, and look very worn, deteriorated, and peeling (insulation plus the rubber outer skin. Is there special insulation material I gotta buy for this project? There's about 3 feet of exposed pipes. The insulation stops at the house siding...and then continues inside the garage about 4 feet. But the insulation in the garage still looks intact. If you're correct, it's only the exterior insulation I need to replace. THANKS A HEAP!!

Just thought of something...if the deteriorating insulation is on the outside of the house...how can that "burning rubber" smell get into the garage?? Hmmm, it's suppose to get to the century mark this afternoon...I think I'll grab a jug of ice tea and sit it out in the garage once the a/c turns on. LOL! I'm just worried that if I don't get it fixed right away, a fire might start!