NO HOT WATER

[tono]

i have just had a radiator changed the guy who fitted it had problems getting the system working again he said there was a lot of heavy sludge in the system when he drained it down also that the pump was on its way out he managed to get the heating working after he left i could not get any hot water and the rads were getting hot with just the hot water switched on he said there could also be a problem with the zonal valve whats the answer to my problem

 

[Fluffster]

Could be a lot of things as you mentioned, however if your boiler is operating as you say the rads are getting hot I would suspect the motorized valve. See if you can manually turn the lever on the side to get hot flow to your cylinder.
Pete

 

[SWOLLENGLAND]

I have just had a similar problem ,my rads were getting hot when the hot water was on .

I was able to establish the motorised valve was the problem by takeing the moter head off the valve and switching between rads and hot water and I could see the motor was turning .
Deduced that the actual valve body was knackered and changed that and all is well. Wether its a diy job depends on how competent and confident you are ,I was fortunate that I have only the one valve thats serves both pipe runs and that I could change it without having to drain the full system,still had some minor mopping up to do though !!!

.Some systems have two motorised valves I understand one for the water and one for the rads so dont know how that would work for you
If the guy has told you its a dirty system you could get it flushed out and see if its just muck which is stopping the actuator or motorhead from turning the spindle in the valve body.
Good luck.