HW not working when CH is on

[buncers]

I have a problem where my HW heats only when my CH is not on. When both are on only CH works. I have insurance for the boiler and heating, but not covered for just heating issues (should have read the small print).

I have changed the mid port valve actuator and the programmer (Drayton for Drayton). I have an Ideal system boiler.

Did some probing in the connector box and found that the HW satisfied is about 50v when both HW and CH is on. 240v when just HW (I guess until hot) and 240v when just CH is on.

Any ideas?

 

[Deleted member 120897]

Is this a new problem, or has it always been this way?

 

[buncers]

Is this a new problem, or has it always been this way?

Relatively new problem, only really noticed when heating went on this winter. Had the system boiler for about 10 years.

 

[Deleted member 120897]

I would be looking at the mid position actuator or the wiring, here’s something to look at regarding testing:

 

[buncers]

Checked out the box with a multimeter and all is as specified above, except when CH and HW are on grey is at about 100V not 0.

Is this the fault, since I assume this is HW satisfied.

 

[Deleted member 120897]

If you’re not getting 240vac where you should then that will likely be the issue.

 

[buncers]

No I'm getting 100vac when it should be zero







Ch and hw on but grey is 100vac

 

[ShaunCorbs]

100vac is nothing

 

[Deleted member 120897]

100vac is nothing

Could this be back feed from a Worcester