Just had a push fit pop off a chromed pipe. I hadn't realised they would be a problem, and thave just installed a rad with chromed pipe. One side has a compression joint, so thats OK, but the RTV I bought had a push fitting. It has been on and working for three days with no probs, then it just slid out. Fortunately the access I cut in the ceiling below is still open, so I can repair.
I had roughed up the ends of the pipe, but not right down to copper. I guess I have a bit more sanding to do. I might try the scribe a line with the pipe cutter trick, seems like a neat solution.
I'm worried about the other end of the tails now - I have replaced the 8mm pipe buried in the wall with 15mm chrome pipe coming through the floor, with a 15mm to 8mm adaptor to connect the two. These were sweat fittings. They soldered OK, and don't leak, but I don't want them to come apart as soon as I've made the ceiling good, or even worse in a couple of years time. I'm starting to regret that chrome pipe ....
Should I take them out and redo the job with plain ol copper? Wrap the joints in epoxy to strengthen them?