I have a problem unsoldering a joint in the airing cupboard which is connected to the main feed from the tank to the pump in the radiator system.
It is a 22mm pipe and I have held the blow torch in it for at least 25 minutes but the joint will still not release itself.
I know that there is no water in the pipe as I have drained the system. I have another joint from the rising main with which I had a similar problem and even with it removed and in the garage and in a vice I still could not release the joint.
Can you advise me on how to remove the joint without cutting the pipe as this would cause even more problems.