Stovebolt.com Forums The Front Office The Greasy Spoon A/C Condenser repair?

I have a pin hole in the rear a/c condenser in my van (vented all the freon into the cabin ... ) Seems to me that all it would take to fix is someone with the right skill and equipment ... probably take 5 seconds to accomplish ... but ... Having a hard time finding anyone local willing to tackle such thin aluminum but a suggestion was made to fix it with J-B Weld. It is an after market unit with no markings ...

Will the JB weld work for this?

There are more videos. [youtube.com]

I would think it would depend if it is on the high or low pressure side.
JB weld or a really good epoxy may work.
But with the cost of freon and the labor fee to recharge, it needs to be repaired right the first time.

Don

Edit: did you notice the odometer read 746,000 miles.

John, JB Weld makes several different types of epoxy. Most of them list Aluminum as a compatible surface. Clean it good enough to eat off of and give it a shot. Good luck.

John,
We build a lot of a/c systems from scratch including crimping on all the hose fittings. Rather than use expensive refrigerant we made an air chuck fitting that screws to the hose on our gauge set that the freon can normally hooks to. This is plugged into a shop air hose (180psi at compressor) and each component is sprayed with a soapy water mixture. If any bubbles it is corrected before filling with refrigerant. We have a filtered dry air line for painting we use but a regular line works fine, just leave the vacuum pump connected for at least a half hour to boil off any moisture before filling. You DO NOT need real high air pressure to form bubbles but we like to test at close to working conditions.

If you have a condenser inside the vehicle, you've got the most oddball air conditioner I've ever heard of. The condenser is that part out in front of the radiator where the hot vapor pumped by the compressor gets turned back into a liquid. The evaporator(s) are what's inside to do the cooling. A condenser operates at around 250 PSI or so, while an evaporator's normal pressure is about 25-30 PSI. No problem so far- - - -until the engine stops and the pressure in the whole system equalizes at 100+ PSI. I don't know of any sort of epoxy that will contain that kind of pressure.

Problem #2- - - - -a pinhole leak in a refrigeration line is like an iceberg- - - - -by the time it starts leaking, the damage inside is cone-shaped and you're only seeing the tip of the ice cream cone. It will continue to deteriorate even if you manage to get the leak plugged temporarily. Bite the bullet and install a new EVAPORATOR. Chances are the condenser is still OK.


Evan- - - -if you use bottled nitrogen like the commercial refrigeration shops do, or even CO2 for a MIG welder to pressure check a new system, you don't have to worry about introducing moisture into the system with compressed air. The 2200 PSI in either bottle can be reduced to any test pressure you want with a welding tank regulator.
Jerry

Good morning John.

I've tried both soldering and tig welding a similar pin hole leak without success. The problem is that the AC system includes oil and that oil coats the inside of every part of the AC system. When heated, that oil seeps into the intended repair area.

But oil contaminated aluminum proved impossible for me to either solder or weld.

In my work as a geologist that I've been at for about 55 years I'm often asked to recommend a way to stop water leaks through retaining walls and basement walls. I've seen a lot of snake oil applied to the insides of the walls and nothing worked. Only patching the outside (water source) sides of those walls has worked and that's a huge project. The same concept may apply to an AC component leak.

Others may have had different experiences.

Ray W

Well, whatever its called (and sorry if I have the nomenclature mixed up... It's the part that the lines run to from the part mounted on the engine with a belt running it. The fan blows cabin air across it and voila -- cold air. Or, in my case, ambient temperature air. It is an after market unit at the rear of the van and secondary/supplemental to the primary unit at the front (15-pass HD E-350)

If it makes a difference, the pin hole was caused externally by a misplaced interior panel screw.

The unit as mounted in the van (just inside the rear door, driver's side) [stovebolt.com]

The unit itself removed from the van [stovebolt.com]

The pin hole itself [stovebolt.com]


I have found several replacement units -- like these (the rear ones) [partsgeek.com] But the attachment points have different geometry. Is this a problem, or can they be adjusted?

Here's an evaporator core that closely resembles the one you have:

https://www.ebay.com/itm/A-C-Evaporator-Core-Rear-4-Seasons-54635/163919140114?epid=79455329&hash=item262a579512:g:NccAAOSwnWFei2hj

Yours has an expansion valve, which makes it somewhat obsolete. Later evaporators will have an "orfice tube" which provides the pressure drop required to begin the cooling process with no moving parts involved, but there might be a compatibility issue with the front evaporator regarding pressure differences between the two units.

That hole is in a spot where it would be very difficult to repair, and I don't think any kind of epoxy would be effective under the working pressures an A/C unit sees. If you can find someone who is exceptionally skilled with a TIG welder, you might be able to flush the unit out thoroughly with a strong solvent like lacquer thinner, blow it dry with compressed air, and attempt a weld repair. The cost would be considerable, however. Since it's an add-on unit, I'd choose to mount a different unit with the blower, housing, and all and adapt it to the existing ducts. Something resembling the under-dash evaporator used with the Vintage Air system is what I have in mind. You might be able to find a conversion van in a salvage yard , or maybe a retired "short bus" from a school system and scavenge the rear air parts, also.
Jerry

2Ton, Nothing.