I've got a combi boiler installed about 9 months ago. The CORGI plumber kinldy teed off from the 22mm flow and return pipes and fitted push fit stop ends to the 15mm pipes, ready for connection to a radiator in an extension.
I don't want to drain down the system if I can help it. As such, could I get away with will the new radiator and feed pipes, fitting push fit couplers, releasing the pressure from the system and then, quickly pulling off the stop ends and pushing on the couplers? Would I need more inhibitor in the new circuit and am I risking air locks>