Refrigerant leak

[Sailorman62]

I have a very small leak in my refrigeration system. If I charge the system up in the spring, it lasts all season but will be mostly, not totally, gone come the following spring. Has anyone tried using any of the stop leak products out there for refrigerant systems and if so, how much is used?
All of the cans I have seen seem to imply putting the whole can in. The entire system only holds 7oz of R-12 so that seems a little unrealistic.
Any thoughts?

[Bill O]

What refrigeration system do you have would be my first question?

Have you found the source of the leak? Do you have a refrigerant leak detector?

Would be better to find and fix the leak rather than adding a "stop leak" type additive. In the long run you will create more long term problems by adding this into your system than a small leak.

[ItDepends]

A couple things, if this is a capillary type system DO NOT, NOT, NOT add stop leak or anything else to it other than pure refrigerant gas. You will clog the capillary and destroy it.

If this is really an R12 system, it must be over 20 years old. R12 has been illegal to manufacture since 1994. The last time I saw a can for R12 for sale it was several hundred dollars since it is not longer manufactured and all of the supply is recovered from systems being decommissioned. Basically, these are unserviceable.

Just replace it. Save our ozone... Take it to someone who is licensed to recover the R12 out of it, do not just throw it away.

[Finalee]

Look at converting to r134a. No atmospheric concerns with it. That's not much of a leak.

[Turtle Blues]

As others have said it is not advisable to add sealant to a system this small.
A leak that does not get terminally worse quickly is going to be on a mechanical seal. The schrader valve is probably the most likely because it has been used. try using good quality brass covers and see if that makes a difference.

[wsmurdoch]

My R-12 leak was a bad rubber gasket under a Schrader valve cover. I found it with a 25% mix of Dawn in water applied with a paint brush jammed up and down to leave a shaving cream like foam over areas where I suspected a leak. Good quality caps come from refrigeration supply houses.

Friend of a certain age gave me cans of R-12 that they had stored in their garages. I transferred the remainder of the can I tapped into a lecture bottle for long term storage not trusting the seal on the tap-a-can.