Honeywell sT9400c

[Garethtrower]

Hi everyone I’m have trouble with my thermostat it’s like it has a frozen it’s on with no light but you can still see the numbers on the lcd screen, it doesn’t respond to when I press the buttons either! Can anyone shed some light on this please many thanks 

 

[Murdoch]

How old is it?

Unfortunately as so much stuff is produced, poorly, off shore these days, they do fail and need to be replaced.

 

[Geoff1946]

Have you tried a new battery?

 

[Sharpend]

What you could try is to remove it from its base (2 small pozi screws) leave off for a 30sec to a minute - perhaps as Geoff suggests replace the battery/s - then replace onto base again.  If batteries are goosed then it will have lost all presets that you’ve programmed. 

Electronic items are subject to freezing from time to time.