I have just found the connection to my radiator is leaking. The compression fitting under the valve is weeping ever so slightly, and tightening it actually makes it worse. I think I have to drain the system, disconnect the radiator, wrap some PTFE tape around the valve stem and reconnect it. I have a Baxi Bermuda back boiler feeding the system. What do I have to isolate to drain the system down? I have a drain valve on the lowest radiator in the kitchen. When isolated, drained down, repair done, How do I fill it up again? It seems such a simple problem to get a plumber out to. Last plumber we had made a bit of a mess with changing a shower, so I'm reluctant to try another. Please Help :?
Assuming you have a header tank bung up both the feed and vent, close the valve on the opposite end of the radiator to the one that is leaking, open the vent on the radiator until it stops running, close it again and remake the join on the valve, reverse the procedure.
You say "......open the vent on the radiator until it stops running......". Surely I'll end up with water all over my hall floor? By "Vent" do you mean the bleed valve?
Sorry, I must be very dim and missing something here?
You will have to catch the water coming out of the bleed valve and it will take some time before it stops running. Refit the bleed valve before you undo the leaking connection and use a towel to catch any water leaks.