heating comes on with hot water...

[Jo_101]

Hi everyone,

I have an indirect vented cylinder for hot water and an unpressurised heating system. All has been working well, but over the weekend the heating comes on with the hot water. Even if the programmer is set to hot water only. Am I correct in thinking that this is probably due to a zone valve stuck open..?

Thanks, Jo

 

[kevplumb]

possibly

 

[Jo_101]

well, ok then...