Boiler coming on when it should be off!?

musharoom

Hi

There seems to be miscommunication between my boiler & thermostat - the timer is set on the thermostat for heating to come on in the morning and evening for a couple of hours and only if it drops below 18 degrees c, which it does.
However, it also fires up whenever it feels like it, middle of the day. The heated towel rail rads in my bathrooms seem to be on permanently (they seem to be the only rads affected), but even when the rads are all cold and appear to be off, the boiler is still firing.

It's a combi boiler wirh wireless thermostat, it comes on even if I'm not using hot water and outside of the times set for heating. I changed the battery in the wireless unit and reset the timings but it's still doing it.

Any suggestions? My partner & I have just this week independently both lost our jobs so we want to try everything we can before calling in repair people! We only bought the house 6 months ago and we've had nothing but unexpected problems since. It's not our year!

rach_k

Is there a pre-heat option set to on? I think that would heat a little water every now and then so you have instant hot water when you turn on the tap rather than waiting a few seconds. I don't mind waiting so we have it switched off. Not sure about your bathroom radiator though, sorry.

musharoom

rach_k wrote: »

Is there a pre-heat option set to on? I think that would heat a little water every now and then so you have instant hot water when you turn on the tap rather than waiting a few seconds. I don't mind waiting so we have it switched off. Not sure about your bathroom radiator though, sorry.

The amount of time the boiler is on at the moment though I would be surprised if it's this! Thanks for the suggestion, I will have a look!

Alex1983

What boiler is it? As above pre heat but with a possible faulty diverter valve Which puts the pre heated hot water into the heating system.

Run the hot water for 10/15mins and see if your radiators all heat up.

Linton

Wireless interference can be a problem with remote thermostats. Have you tried changing the frequency?

Alter_ego

Have your neighbours got a wireless thermostat?

musharoom

Alter_ego wrote: »

Have your neighbours got a wireless thermostat?

That is an interesting consideration - they moved in 6 weeks ago and have overhauled everything, so quite possibly have installed a new wireless programmer/thermostat. I shall have a chat with them!

musharoom

Linton wrote: »

Wireless interference can be a problem with remote thermostats. Have you tried changing the frequency?

Is it a fairly straight forward job? I'll get the manual out again and investigate! Thanks

kev25v6

My heatmiser wireless stat kept losing contact with the boiler and by default the boiler kicks in for 30 mins to try and re establish the connection. Yours might be doing the same.

LUHG1878

We had exactly the same issue, once the frequency on the thermostat was changed, problem solved.

From recollection, had to change on the thermostat and the receiver in the boiler.