Why is my heating coming on?

muskoka

Happy New Year to one & all.

Got up this morning to find my heating on - Vailant 28 Pro boiler - Honeywell remote CM921 one day programmer. Set on auto - shouldn't be on at this time of day. Anyone any idea please why this is occurring. Have checked times, etc on programmer & heating should not be on....

Bit strange as my gas/electric usage is £140 per month (ya , I know - mega bucks) and I'm at work full time, so assumed it was down to being a solid wall house. However, now wondering if theres a problem that needs dealing with...Thanks

withabix

Is the 'Off' mode temperature set too high on the CM921?

muskoka

Off t emperature showing at 5 - frost temp

withabix

Communication fault between the wireless programmer and the control box?

Low batteries?

Programmer not sending radio signal to control box?

What lights are showing on the control box?

Neighbours have same programmer?

muskoka

Turned the remote temp down to 17, but room temp is at 20. Hence heating now gone off BUT shouldnt have come on in first place - scheduled in morning to be on 6-7am only... Weather is extremely mild today, so heating should not have fired up

Control box for remote...(think you mean the box under the boiler that shows a light when heating is on). It only has one light - a green one when it is on....is that what you mean?

Low batteries- how would I know? Or just put in new batteries & see if any different... Thanks

Little wireless icon comes on when I increase temp on remote, so think thats ok

withabix

If the battery symbol in the top right hand corner of the display is flashing, change the batteries.

Have you got the thermostat/controller fixed to the wall or do you move it around? If the latter, there could be something interfering with the signal?

muskoka

No battery light flashing & yes I do move the controller around, though had it in kitchen (where boiler is) and lounge this morning & boiler was firing up with controller in either room . Now sitting down with book trying to see if I have done something wrong.....(wish the print in the book was bigger- is difficult to read its so small)

Now read right through book and nothing indicates an incorrect setting or otherwise, hence no idea why heating

muskoka

Read right through book. Nothing in there indicates an incorrect setting or otherwise.

Adjusted temp up on CM921 to (21) above room temp (20)(STILL SET ON AUTO), and should NOT come onthis time of day), Boiler has fired up ......def something amiss.......?

Ruski

You just said that you adjusted the target temp to 21 - how did you do this - with the program or the +/- buttons??

muskoka

adjusted temp with controller - (as per book instructions...)

Pressed i button on right of controller then pressed up arrow next to i button (all on right of controller)..

Ruski

Well what you've done there is overridden the programmed temperature so it will now obey the manual command to come on and will 'reset' on the next programmed phase. Think of it as a manual override for one of your programmed commands.
Same as my CM927.
HTH

Russ