How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Phil Your Own Question
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 5648
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
Type Your HVAC Question Here...
Phil is online now
A new question is answered every 9 seconds

I have an old Honeywell Chronotherm thermostat and cannot figure

Customer Question

I have an old Honeywell Chronotherm thermostat and cannot figure out how to make it work. The clock is no longer working. It has a button below that triggers either a blue dot or a red dot to show up. When I look at the workings, the red or blue dot change the position of the mercury switch but my heat doesn't seem to be turning on. I cannot find a model number to find a manual. It seems to be an example of the earliest programmable thermostats.
Submitted: 5 years ago.
Category: HVAC
Expert:  Douglas replied 5 years ago.
Hi, I'm Douglas and I am here to help you resolve problems with your heating and cooling equipment.

Can you remove the thermostat from the back plate to expose the thermostat wires? If so, grab a paper clip and make a rudementary jumper and hold it on the R terminal with the Red Wire and the W terminal with the White wire and see if the heat comes on...

We are going to see if your problem is the thermostat itself or if you have another problem.

If you have a second person there, have them go to the furnace and watch for a reaction.
Customer: replied 5 years ago.
Hi Douglas.

I cannot do this tonight. I'll have to try in the morning. Thanks.
Expert:  Douglas replied 5 years ago.
OK, let me know.

Related HVAC Questions