Some things about refrigeration systems that you may not be aware. If you puncture one of the lines (pipes) and it is running, these lines can carry pressurized refrigerant of up to 400 psi (hot summer day). When it comes out of a little hole, it can come out as hot gas that can burn, or liquid and freeze what it touches (all mixed with oil).
If it is an absorption system (some refrigerators and a few A/C systems), the gas (or liquid) could be ammonia, some are other refrigerants that are highly dangerous. I have even worked on alcohol (cryogenic) systems. Every one of them can be very dangerous if you don’t know what you are doing and have the correct tools, etc… Even breathing the escaping gas can be extremely dangerous.
There are somethings that are best left to the professionals. I had a Master’s License and Stationary Engineer’s License and as such, I was licensed to work on anything in the State of MD – A/C, chiller, or boiler, but since I don’t have the tools anymore, I call someone else to fix it. Even though I was trained for ammonia and other absorption systems, I did not have the tools to work on it, mostly because I didn’t want to. The stuff is dangerous to the point that if you have a leak and you breath it in (and smell it) your lungs are already blistered.
-- Love woodworking and fixing most anything