R22 to R502 machine for leak detection

[sgntlc]

Would it be ok to pressurize a R502 taylor soft serve machine using r22 or r404a to find a leak? I have a freon/halogen leak detector but it doesn't detect r502, but does detect 404a and r22.

thanks

[bohncoils]

Would it be ok to pressurize a R502 taylor soft serve machine using r22 or r404a to find a leak? I have a freon/halogen leak detector but it doesn't detect r502, but does detect 404a and r22.

thanks

If you're going to recover anyway, why not nitrogen?

[prorefco]

Would it be ok to pressurize a R502 taylor soft serve machine using r22 or r404a to find a leak? I have a freon/halogen leak detector but it doesn't detect r502, but does detect 404a and r22.

thanks

It's certainly ok to use r-22 for leak detection... But I have to ask, what kind of leak detector do you have that will detect 22 but not 502? Also, are you planning to recharge with 502? If so I would assume you have 502 on hand...

[jpsmith1cm]

It's certainly ok to use r-22 for leak detection... But I have to ask, what kind of leak detector do you have that will detect 22 but not 502? Also, are you planning to recharge with 502? If so I would assume you have 502 on hand...

I've never heard of a detector that won't detect 502.

Please be specific as to brand and model. I'm quite curious.

As long as you're pulling a vacuum, it doesn't matter a whole lot WHAT refrigerant that you use as a trace gas. You'll be taking it right back out again.

[crymtide]

I'm more into nitrogen and bubbles. 1st high pressure 200psi+ and listen then dropping in 50 lb increments and finishing at 5lbs. A lot of leaks hide in high pressure by blowing the big blue away and not bubbling. Also a 502 machine is old and if you don't find the leak it's in the block of insulation covering the barrel and holding tank. If it's in there you can forget it.

[sgntlc]

It's one of those cheap harbor freight detector. It works great for the money and has always found my leaks.
I am planning to recharge to with 502

[jpsmith1cm]

It's one of those cheap harbor freight detector. It works great for the money and has always found my leaks.
I am planning to recharge to with 502

If it will detect 22, I'm pretty sure it will detect 502, too.

[prorefco]

If it will detect 22, I'm pretty sure it will detect 502, too.

Correct me if I'm wrong but I believe 502 is an azeotrope of 12 & 22?

Look, get a H-10 leak detector, it will work with just about all refrigerants and better than any other....

[jpsmith1cm]

http://www.refrigerants.com/msds/r502.pdf

R115 and R-22, actually.

[sgntlc]

Also a 502 machine is old and if you don't find the leak it's in the block of insulation covering the barrel and holding tank. If it's in there you can forget it.

Actually I found the leak and it is in the insulation where the barrel is. I had to cut the mild steel covering the insulation to find it. It's made of steel not copper and it is somewhat difficult to access.
I don't want to replace the whole barrel as Taylor is asking $2,000 for that assembly. Does anyone have any suggestions? weld, braze.

thank you

[crymtide]

Basically it's your choice as you are walking outside the normal repair zone. keep me informed as I run into a lot of mom and pops willing to chance repair of ancient equipment rather than buy something with less issues.

[Fridge Repairer]

We were taught in school, if you use R22 as a trace gas to add vapor R22 to 5 psi then top that off with 100psi nitrogen. It does not take much R22.