Hello,
I understand you should not run plastic pipe up to the boiler in case it boils the water and melts the pipe. What is the recommended distance before you can use plastic? I think you have to use 2m copper first but I don't know whether I have read that figure somewhere or just made it up!
I am hoping to change my gravity fed system to fully pumped. Using plastic will be easier to thread under floorboards and through joists.
Do the same considerations apply at the cylinder end? We have immersion heaters that use economy seven. Do I need to have a copper run at that end in case the immersion heaters boil the water too?
Thanks.