Just to finish this, i called a plumber in, turns out the pump was still turning inside but was heating everything so slowly that it never got the heat downstairs.
changed the pump and now works like a dream.
many thanks to all that tried to help.
hi gas 4 you
ok was planning to do the screwdriver trick but the silver pin won't come all the way out, not sure if maybe the thread has gone a bit???? or whether it just doesnt come out, so cant check if pump running properly
i did get some more black water out so some kind of silting up...
johnD
ok i've read what you recommended, may thanks I will try balancing them when i get home. It might be the case as the upstairs ones were very hot.
Strange that it happens all of a sudden, but maybe as using it more now summer has been and gone?
i put the big about the valve in big...
reply to agile
yes got charged a lot of money before just for turning a water stop valve on. but apologies
i also think female on her own, can pull the wool over.
a
again same problem, cold radiators down stairs boiling hot ones upstairs
its a myson condensing boiler (water tank upstairs in airing cupboard)
upstairs rads seem connected together but the downstairs ones seem to be connected with individual in and out pipes.
turned off upstairs ones and...