I have a very old manual Chronotherm thermostat.

It must be wired or it will not work.
Take a look at the installation instructions before you attempt any reconfiguration!

It's pretty basic actually. I've done this with Nest and Honeywell Lyric. The only thing you need to do is removing the current thermostat from the wall and connect the new one.

Set it up using your mobile application and you're good to go.

Here's a manual for your unit. https://customer.honeywell.com/resources/techlit/TechLitDocuments/69-0000s/69-0690.pdf Here's another link to trouble shoot your problem. http://archives.hvacmechanic.com/archives/228

R= power in G= fan Y= cooling W=heat O= heatpump reversing valve C= common used for clock on chronotherm Usually its pretty streight forward wire for wire. Unless you have a heatpump. The thermostat has to be heatpump compatable. And I ll usually use the 8000 for this. The w and y jumper may not be necesary on the new thermostat as the new one should do it internally once programed as a heatpump thremostat. At least thats how the 5000 and 8000 sreies work. So imagine the 7000 would be the same. You may also have to program the reversing valve operation not all manufactuers do it the same . Some valves have to be powered for heat while others have to be powered for cooling. Good luck

Unfortunately, no. These clocks fail frequently.

you are not geting AC power from the furnace

The Chrono Therm 3 and 4's were some of the worst products that honeywell has EVER put out. I would suggest switching to the Vision Pro 8000, please consult your local HVAC company for more information regarding the change over.

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/cody_17f08cf8e340c06c

Hi, your replacement part can be purchased on amazon, take a look here: Amazon com honeywell chronotherm III thermostat. I hope this was helpful. Cheers

The two wires from the transformer are to run the clock in the old thermostat. If you connect the two other wires to any heating thermostat, it will work. Don't forget to disconnect the transformer wires. Hope this helps

There are no batteries on an 8600-8601-8602 series