No hot water...advice & help needed please

[dazzystar]

Hi all,

HW light is on on the programmer yet the boiler (Potterton Prima F) does not start up. If I turn the CH on on the programmer the boiler fires up without problems. I can hear the HW zone valve opening and closing if I turn the HW on and off from the programmer.

I've having to use the immersion for HW which costs a ruddy fortune and of course the rad in the bathroom is cold so no dry towels!

Does anyone know what could be causing the problem?

Cheers
Daz

 

[craig51]

If the motor is moving, then either the Microswitch is buggered therefore not send power down to the boiler, or, the permanment live is buggered.

I would go with the microswitch my self.

 

[dazzystar]

Thanks for the reply. If there was an issue with the permanent live wouldn't that also affect the CH?

Is there a way of me manually testing?

 

[craig51]

Each valve has its own permanent live, so the pl going to the h/w valve might not be good, but this is unlikely all else being equal.

If you had a multimeter, you could test the m/switch.

 

[dazzystar]

Here's a quick update. I've managed to use a wooden skewer to press down on the micro switch and I can confirm that it starts the water pump but the boiler still refuses to light.

As I understand it there is only one cable which sends the signal to the boiler to start up and the fact that it does start when I turn on the CH would indicate that that cable is fine.

What else could be causing the problem?

Cheers
Daz

 

[dazzystar]

anyone?