I want to add 2 radiators, upstairs, to the existing system in our 3 bedroom property. The system is a standard 15mm feed pipes with a Worcester Bosch combi boiler. Is it OK to close all valves at the radiators and drain off just enough water from the system to just below the level of the pipes feeding the upstaires radiators. This will allow cutting the pipes without draining the whole system.
Many thanks.
Many thanks.
