I just fitted a new boiler, which worked fine apart from a dodgy TRV on one of the rads which i have changed today, all other radiators were working fine. After refilling the system(i had had cleanser running through system) and firing up the boiler i now have a radiator that does not heat up, although prior to draining it worked. The pipe to the valve is hot, as is the valve itself and radiator tail, but the rad itself is stone cold. What has happened in the period of time from emptying the system and refilling it?
And yes i have bled every radiator.