No hot water but CH works fine...help please!

[flood]

It's a kingfisher MF, about 5 years old. Has been working fine but recently the HW facility has stopped working. The boiler fires up, the flame light comes on but around 2-3 minutes later, the boiler turns off.

There's no red LED indicator coming on and the reset button does nothing too.
After following the troubleshooting in the manual, it seems the overheat thermostat is working (i think) and the only thing left is to change the control board...any suggestions? help? advice????

Please help, it's getting too warm to be turning the heating on for HW!

 

[Agile]

If it works fine on Ch then its nothing wrong with the boiler.

The fault will be associated with the motorised valve(s).

If you have two you should be able to manually open the HW one!

More info needed on valves!

Tony

 

[flood]

Thanks for the reply, some more detail...

There are no motorised valves...the HW is gravity fed and when the CH is on, the water heats up - there's no way of stopping this

Right now, the CH is working as usual and its the only way of getting hot water.

The pump is only for CH.

This is what happens when the HW is switched on... after a couple mins the boiler turns off. Then there is a clicking noise - It seems to be the relay on the control board, clicking on and off. After a few clicks it just stops...

I'm totally lost, it's a bank holiday and my car broke down yesterday!

 

[BingoBongo]

does your oven work??

if so stick yer head in it

 

[flood]

you won't believe it but I've just broken my bed...can't make this stuff up!

Any more help please????

 

[flood]

Guys...anyone....a little help...??

 

[mlcinfl]

Sounds like your header tank (the small plastic one) has run dry, probably due to the ball valve sticking in the closed position (horizontal).
The header tank keeps your system topped up with water. As a central heating system doesn't actually consume water, any usage is mainly due to evaporation, so the ball valve could have been stuck for several months. Once the water level within the system drops below the level where the DHW flow pipe enters the hot water cylinder gravity circulation ceases.

Turn off the system at the programmer, free off the ball valve and allow the system to fill. Vent the upstairs radiators then turn on the hot water function, your water should now heat up.

Make sure that the ball valve re-seats properly (stops water entering the tank when the tank is full). If not, then replace the ball valve.

 

[twgas]

you won't believe it but I've just broken my bed...can't make this stuff up!

Any more help please????

leave the missus alone in future, or be gentle

 

[flood]

Thanks for the help, it's working now! Saved me £90 for a pointess PCB board and then a call out charge just for the guy to move the float.

Cheers guys



The missus is happy, too!