Heating only works when Water On

[g60racing]

Hi,

We problems with our CH.

Having checked the system when I put the CH on the rads do not heat up, but if I then also put the HW the rads do heat up.

When I switch the HW on I can feel a pump near the cylinder come on, should this not come on when the CH is switched on also?

We have only moved in a few months and have had little reason to turn the heating on so far.

Thanks for any help.

Jason

 

[ChrisR]

We need more details of your system. Motorised valves in evidence??

 

[gas4you]

Sounds like the microswitch had it in the ch zone valve head, assuming you have one.

New valve head needed.

 

[ChrisR]

Wrong wiring is also an even bet!

 

[g60racing]

Sorry,

Their is a motorised valve (Sunvic SD 1602), I removed it to inspect and it appears to turn its complete throw when I turn the from the control unit to CH ON.

The boiler is located on the ground floor, controls and cylinder are upstairs with a pump and a motorised valve.

 

[kofi2003uk]

dont know much about central heating but i had the same problem when i moved to my curent house.
turned out that was the way it was wired. i got an engineer in to change the programmer and the wiring and it has worked fine since. the guy said to me that some systems are wired like that.