No hot water unless house central heating is on

[DanD]

I did post on an old thread that had a very similar issue to mine, but did not get a reply so I hope I'll be excused for starting a new thread.

I have an Ideal icos boiler and a Range Tribune HE which will only supply hot water when the heating is on. If on the 'water only setting' the boiler does not fire up. I have looked at the two way valve and it does not appear stuck, and the small red wheel on the unit does rotate, which indicates the valve is free also. However, the wheel rotates until the flat part is not visible which is when the valve is shut.

Is it possible that the unit PCB is telling the boiler not to fire because it is automatically shutting? And, if this unit is faulty, where can I get a reasonably priced replacement? I have attached some pics to help.



Thanks in anticipation of your time and effort.

Dan.

 

[Whn1]

The unit won't tell the boiler not to fire, only to fire, could be a wiring issue/ programmer/ cylinder stat/ falty valve.

 

[DanD]

The unit won't tell the boiler not to fire, only to fire, could be a wiring issue/ programmer/ cylinder stat/ falty valve.

Could it be that the actuator is faulty and closing the valve?