Central Heating does not Cut Off Ideal

[Sara]

Hello, I'm be grateful if anyone could give me advice please. I have an Ideal boiler with a Honeywell CM921 Thermostat. The central heating does not cut off. The domestic hot water is not a problem. But the hot water, no matter what temperature I turn it down to does not go off and I have to turn it off at the boiler to switch it off. I have renewed the batteries with new good batteries but that hasn't made any difference.
Many thanks for any helpful hints. Sara

 

[Dotty]

Hello Sara. Do you have a hot water cylinder in your airing cupboard or is your boiler a combi?

 

[Sara]

Thank you Croppie. It is a combi.

 

[lame plumber]

get an engineer in to check room stat working properly

 

[Sara]

Thank you. Do you know approximately how much is a new one if we need to replace. Just a rough idea. By the way all the switches seem to work, all the buttons, it's just that it doesn't seem to be able to turn the central heating down as if the communication has stopped.

 

[lame plumber]

reboot it iaw instructions as if a new install

 

[Dotty]

These are your instructions here -

http://www.google.co.uk/url?sa=t&so...iegNAN&usg=AFQjCNFgNJVgxITPsPZevuI5ZdNsP1LIqQ

 

[Sara]

Thank you very much for your quick replies LP and Croppie. Is there a way of switch off the Thermostat so I can restart and reset it? Thanks.