Heat and hot water but not just hotwater

[noah472]

Hey everyone,

I am looking for a few ideas, I am not sure if its an electrical problem rather than a plumbing one. I have an old Ideal Elan 2 gas fired boiler which is connected to a small hot water tank. When i select heat on the programmer it works fine, the whole house gets very hot very quickly and the thermostat in the living room works to control the whole system. When I select just hot water the bolier doesn't seem to receive the call, no lights come on and the boiler doesn't do anything. The tank stat clicks when the dial is moved, I have tested the two lives when moved against a tank full of hot water and there is continuity on one live before it clicks and on the other after for within a few degrees, at the upper end there is no continuity. I am unsure how to check if the stat itself is working. There is a:

Honeywell F-5 0735
Sundial Y plan
3 Position Diverter Valve
V4073A1039

electric port connected to the system but as the lights don't come on on the boiler when the hot water only is selected then its probably not a port issue?

Any ideas gladly received, its not a huge problem but seems silly to have the CH on in the summer!

Thanks very much!

 

[bellairaphon]

You need to determine which wire is the common to the cylinder stat and make sure your getting 230v there and that your getting 230 when the cylinder stat is calling for heat.

Nathan

 

[bellairaphon]

Also the hotwater on doesn't need the valve as the valve is hw priority.

 

[noah472]

Should there be 230 all the time or only when the programmer is calling for hot water?

thanks!

 

[bellairaphon]

Yes only when there is a demand for hw. You will get 230v on the grey on the 3 port when there is no demand. Or the cylinder stat is satisfied.

 

[noah472]

okey dokey..... I will have a look tomorrow, thanks!

 

[bellairaphon]

No problem