Heating and water

[Fed up]

Hi

We have a combi boiler and when we turn the heating and hot water on we get which ever we turned on first and not the other one. Hence if you turn the heating on first you get no hot water and vice versa. A Gas Man came round and he has changed the valve but this has not helped and he is telling me he can't do anything else and I need an electrician to check the connection to the valve! It is very strange as both do work individually but not together and when you put the heating on first the pipes are hot around the valve and pump but the water tank stays cold and hence we get no hot water! The gas man says he is confused so am not sure he can help me......

Please help as I really don't know what else to try as both work fine individually Thanks in advance.

[Hard@it]

Sounds like a wiring fault or a micro switch not doing it's job.Is this a new installation. Are you switching on from the programmer, if so it's wiring and down to electrician. If that is ok, take a direct live and neutral to the boiler and run and see if the same happens then it is a boiler fault.

[pilotlight]

Fed up, Not quite understanding what you mean by " not working together ". A combi is not designed to give heating and hot water at the same time - it will always give preference to hot water, i.e. when you are drawing off hot water, the boiler does not supply the heating system. Your controls to the boiler should be set to give hot water 24 hrs.

Presumably the heating is o.k. when not drawing hot water, and hot water is o.k. when heating is not on. If so, the problem is "no hot water when the heating is on ". This would suggest diverter valve problem, possibly printed circuit board.

Hope this helps.