Honeywell CM927 timer

[gavsdad]

My elderly mother's central heating has been renewed which includes a honeywell cm927 wireless stat + timer, eventually got the daytime settings to her satisfaction but she now compains that the boiler is coming on occasionally through the night! The timer says the heating should be off till the morning, is there a frost stat on the timer? better still can it be adjusted, have read the instruction book several times but cant find anything about through the night settings.

Chees John

 

[secret squirrel]

Depends on the temperature and where the stat is located.

I have the same stat, it is located in the coldest room of the house which is my dining room. The temp is set at 14 degrees from 10pm (I think). Although the rest of the house is higher than this temp the room stat hits 14 and tells the boiler etc to come on.

Therefore, your boiler is coming on as it is told to by the room stat. If the battery in the stat fails the default setting is 5 degrees so it will be pretty cold for this to come on.

The idea is that the programmable room stat now controls the temp of the house. The heating on the programmer should be permanently on.

Hope this made sense.

 

[shaky]

When you set the timer to go off you also put the temp in when off let say you set it to come on at 1630 then go off at 2200. At 1630 you set the temp at 22c so the boiler will come on untill it gets to that temp. When you set it to go off at 2200 it also ask what temp this may be 15c so even though the programmer is off if the room temp drops below 15c the programmer will be override. So try setting the tenp a lot lower when off.