Firstly, forgive me for being a muppet if you're a gas fitter but I'm a chippy that doesn't have a great deal of knowledge about pipe work for rads!
I have just built a 6m X 6m extension on the back of my house with a vaulted ceiling and having used an online calculator it seems that I needed to have something like 20,00 BTU in there. I installed 2 X vertical rads (that I could hardly lift and I'm a 17 stone lump!) that were something like 10,000 BTU each. Unfortunately, they're not heating up very well. I have a feeling it's because I've run them in 15mm pipe work. Is this the case and should I now change it to 22mm.
Thanks fellas (and ladies if there are any!)