Boiler running constantly

[Johnking]

Just this morning my boiler (Vailant Turbomax 282e) has started running constantly - the heating is always on. This is regardless of the position of the switch on the timer. If I turn down the thermostat on the boiler, it does cut out (though of course the pump continues to run). It still provides hot water when demanded.

Seems to me like the timer/controller is kaput - it's one of those with a green "clockface" and little switches round the outside for each 15mins.

The boiler's pretty old, but it works fine, I'd rather not replace it. If I'm right, can the timer be fixed / replaced?

 

[slup]

Do you have a room thermostat?

If not (and it sounds like you don't), then a good upgrade would be to fit a decent programmable room stat. A separate consequence of this will be that it will fix your problem!

Something like a Honeywell CM907 or the wireless version the CM927

 

[Johnking]

Do you have a room thermostat?

If not (and it sounds like you don't), then a good upgrade would be to fit a decent programmable room stat. A separate consequence of this will be that it will fix your problem!

Something like a Honeywell CM907 or the wireless version the CM927

Sounds interesting, could this be retrofitted? Could I do it myself (reasonably proficient DIYer).

 

[namsag]

Sounds like the microswitch on the divertor valve is stuck ,thus the boiler thinks there is a hot water demand but as the divertors rest position is for CH then the heat is going around your rads.

 

[slup]

It's probably the single most straightforward thing you could do to your heating system.

It just connects to pins 3, 4 and 5 on your boiler.

3 = Live
4 = Switched Live
5 = Neutral (if needed)

I'm no boiler engineer though so you need to listen to people like namsag!

 

[Johnking]

Sounds like the microswitch on the divertor valve is stuck ,thus the boiler thinks there is a hot water demand but as the divertors rest position is for CH then the heat is going around your rads.

Interesting - I have previously had to change that microswitch.

Having left it powered off for a few hours, I find that it's now got no problem. time for some watchful waiting.