"David W." wrote:

"Punch" wrote in news:%Y1Gb.7254$d%1.1600823
@news20.bellglobal.com:


"Ignoramus28269" wrote in message
...
In article , Doug wrote:
Ignoramus28269 wrote in
news:bs9qob
:

Recently, one day before we had to go on vacation, our house
thermostat quietly stopped telling the furnace to turn on and quietly
displayed a LOW BATTERY warning. We noticed it because it started
getting cold. A change of battery took care of it.

now if the thing beep'd to tell you it was low/dead you would be posting
here telling us this damn thermostat won't shut up ........

And that still doesn't help when it starts beeping the day after you've
left, when the rechargable battery fails because it has never been
replaced, or the thermostat just plain fails.

All of the programmable/setback thermostats I've seen were powered from the
furnace control 24V power, with a 9V battery to save the clock and settings
through a power outage. I'd never buy (or keep) one that was battery only,
for just the situation the OP described.

I'm sure that someone from the alt.hvac could respond to this, but I have been
in over 300 houses as a buyer of distressed property and also as a property
manager, and I have yet to see a thermostat with a 9v battery. The only "power
stealing" electronic ones I have seen are the Honeywell Chronotherm III (and
now IV) which cost upwards of $150.

That said, a decent set of batteries usually lasts me 2-3 years in the
thermostats in my rentals.

JK