I punctured the heat exchanger

[chenzo]

I'm new here and joined specifically to try and get advice on how to fix the fridge that I may have destroyed (grinning sheepishly).

I am in the process of converting a mini-fridge (a capacity of about 4-CF or so) into a mini-kegerator. I brew my own beer on a regular basis and have progressed from bottling to kegging the beer and now want to have it on tap 24/7 at home. My design will require me to punch a small hole (approx 3-inch diameter) in the top of the mini-fridge where I will install the draft tower, thus allowing the beer line to be cooled (prevents excessive head).

While drilling "exploratory" holes in the top of the fridge, I accidentally made a small pinhead sized hole in the heat exchanger and released all of the refrigerant (oops). It seems that I can repair it by soldering a small patch of copper over it. I've checked the specs and the Design Pressure on the Low Side is 0.83 MPa (120 PSI). Once I patch the hole, I figure I can take it to an appliance repair shop and have the system recharged. Has anyone ever heard of fixing a fridge like this or am I just wasting my time? I'm not so sure that a soldered patch like that can withstand a pressure of 120 psi. I've already dug out the insulation and can easily access the area in question.

Also, I'm not entirely certain that I'm using the correct terminology so if it's not clear what the situation is, I can try and post pics to help clarify.

Please Help!

[frank]

Do not use ordinary plumbing solder. The pipe needs to be either silver soldered or brazed.
If you are taking it to the shop to have it recharged then maybe the tech can make the repair for you although the heat may ruin the surrounding insulation