Calling all HVAC gurus!

[Nick1911]

Question:

Is R134a compliant with brass and copper?  If so, would there be any pressing reasons (galvanic corrosion, etc) to not use brass compression fitting and copper pipe to repair a section of aluminum pipe in an A/C system?

Thanks!

[41magsnub]

Question:

Is R134a compliant with brass and copper?  If so, would there be any pressing reasons (galvanic corrosion, etc) to not use brass compression fitting and copper pipe to repair a section of aluminum pipe in an A/C system?

Thanks!

I am not a HVAC expert, do not play one on TV, nor did I stay in a Holiday Inn Express last night but I can relate what happened in a server room at my old job.  The original HVAC guys put in a copper pipe for the drain line and the waste water ate its way through the pipe and then drained into a server rack one night.  It took 4 years for it to happen.  The guys who repaired it used PVC and said the original installers should never have used copper.

The other obvious question is why would the drain line go through the ceiling over the data center...

[280plus]

Hmmm, aluminum is notoriously hard to repair. A compression fitting (meaning has a brass ferrule and nut) is not normally used in refrigerant systems, it probably will leak. You would need to use flare fittings. If you oil everything up real good and you can flare the aluminum tube without cracking the flare, it might work. Galvanic corrosion may very well occur over time. Dissimilar metals and all. Don't really know, never tried this.

Did someone poke a hole in the freezer with a knife cause they was "defrosting" it? 

Or is it a car?

[Nick1911]

Did someone poke a hole in the freezer with a knife cause they was "defrosting" it? 

Or is it a car?

It's a 2001 saturn, my finacee's car.  If you ask me, 2001 is way, way too new to be having this issue.  I'm thinking of brazing it.

I hate trying to join aluminum.  It goes from solid to liquid with *no* indication, and oxidizes fast.  Maybe I can use this as a bargaining chip to get the fiancee to agree with a TIG welder? 

[Mabs2]

I dunno about cars for sure, but I don't see why not.


<--noob though.

[mfree]

You'll get galvanic issues after a while, but it'll serve as a quick fix.

Whatever you do though, after you get it sealed up, pump it down and let it sit a while, and pump it down some more. Corrosion's from water in the system interacting with the working fluid, which is also why you may consider changing the drier out too.

[280plus]

Which means you'll need a vacuum pump and gauges.

[Nick1911]

Which means you'll need a vacuum pump and gauges.

I have a decent gauge set, and a much less decent (but functional) vacuum pump.

[280plus]

There you go! 

[Nick1911]

New solution - replacement hose from Pick-n-Pull off a smashed up Saturn.  Cost - $10.77.  Can't argue with that!