CM907 time falls behind

[Pthomass]

Hi,

I have 3 pieces of Honeywell CM907 thermostat in the house for my years. The one in the bathroom is the oldest one.

This one does not hold time. Whenever I set time again to the correct time, it starts to run behind over time. It does so slowely, meaning it now runs behind over an hour while I reset it some years ago.

Anyone an idea if this is just one with a faulty board or can this be fixed?

 

[kidgreen61]

Seems to be a common fault with them, hard to believe given that digital clocks have been around for years.

Fortunately, it's very easy to correct the time

 

[Pthomass]

Hmmm...
So it's embedded in the hard/software then
Then indeed, adjusting time every now and then will be the only solution

 

[Pthomass]

So the clock is an hour or so behind time since the last time you set it which was some years ago?
Has the programmer been set for auto GMT?

no,
It just “counts” wrong
As if it is missinf a second or so per day

by now that has cumulated to about an hour