october? must be time to replace my broken thermostat!

october? must be time to replace my broken thermostat!

This is the second year in a row this has happened....Is it just me?

I have steam power. I replaced the plumber-installed thermostat for FHA (!) with a Honeywell T860202000 (reading from the back of it). This has settings for steam (gravity) heat and setback.

Last year, come the fall, the batteries were run down, and when I replaced them the thing was inoperable. Display shows operation, but no temperature displaying. Putting it into test mode, nada from the boiler. Take out the wires and hold them together (switching off the circuit in the intervening), boiler fires up, so it's not the boiler.

Bring it back to the supply house, they replace it (I have to check my credit card statements now to see if I got the refund). Now a year later, we're right back where we were last year!

Supply house tried to say, and will try again this year, that it got knocked out by a thunderstorm. Now, call me simple-minded, but we do have thunderstorms now and again, doesn't affect any of the other electronics in the house. Are you telling me that whenever the skies rumble, I need to get down on my knees and beg Thor to spare my $200+ thermostat? I mean, ****??!!!

Can anybody suggest a better thermostat? Or a diagnosis of what's going on?

And how come this expensive POS only runs on battery power and cannot steal power from the boiler?

Sorry if my \"POS\" comment caused offence

...my frustration bled through.... I'm just surprised that such an expensive thermostat cannot steal power when it seems like the cheapos off the shelf at HD can (like the one I had before).... Does Honeywell not have the technology?

In any case, thanks for looking into this for me....

Thanks for looking into that!

"Power surge" sounds consistent with the thunder storm hypothesis. But I still say, surely they make these things more durable than that, that a summer thunderstorm can reliably blow one out once a year.

An alternative hypothesis: This is a 1929 house, don't know how old the insulation on the wires is, but it's pretty ragged (ragwire) coming out of the wall. Eventually when I redo the basement I plan to fish a new wire down there, in the meantime I've wrapped electrical tape around the conductors coming out of the wall. In the meantime is it possible there is arcing somewhere in the wall due to deterioration of insulation? But I expect we'd see the boiler firing up erratically if that were the case.

But none of this explains (to me) the too-rapid drawdown in battery power. And the fact that failure follows battery depletion.

Thanks for the recommendation on the T8600!

Thanks, still working on it

Waiting to hear back from supplier re replacement, who needs to talk to distributor.

Supplier thinks there's something wrong with home wiring, so I'm going to get an electrician in to take a look. He does not carry 8600, says too many problems with incompatible boilers [boiler is Utica PEG150C]. Also distributor may not agree to replacing 8602 with 8600, and may not agree to a second replacement when he feels the problem is mine, not the thermostat's.

Now I've had 2 thermostats before this, both power-stealing, one cheap with no setback, another for FHA (plumber's fault). No problems with either. I would expect *less* problems with battery-operated than power-stealing....