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 Tommy Tesla Your Own Question
Tommy Tesla
Tommy Tesla, Electrical Technician
Category: Electrical
Satisfied Customers: 139
Experience:  E-1 Master Electrician. Specializing in Commercial ,Industrial, and Residential Wiring Applications.
Type Your Electrical Question Here...
Tommy Tesla is online now
A new question is answered every 9 seconds

Installed new Honeywell RTH221. In "HOLD" mode AC works cor

This answer was rated:

Installed new Honeywell RTH221. In "HOLD" mode AC works correctly, however heat does not. When I set the desired temperature above room temperature, I hear a "click" from thermostat but furnace doesn't start. If I move the fan switch to "on" the fan starts and I can hear the forced draft exhaust fan running, however the furnace doesn't light off. I tagged the wires as I removed the old thermostat so I think they're attached correctly. The red, multi-strand wire labeled RC is attached to the RC terminal; the white wire labeled W is attached to the W terminal; the green wire labeled Y is attached to the Y terminal and the 2nd red wire labeled G is attached to the G terminal.

I'm second guessing myself and wondering if I should swap the terminals of the green wire and the 2nd red wire in case I did get them mixed up?
Is there a jumper wire on the thermostat between RC and RH? Also if you remove the jumper then the red wire you have on the G terminal needs to go to RH.
Customer: replied 3 years ago.
Yes there ais a jumper between RC and RH. I will try what you suggest and get back to yuu.

Customer: replied 3 years ago.
More on what I changed. There is no RH terminal on the thermostat, just R and RC. The jumper was between them. I removed it and installed the red wire from G into the R terminal.


Is the furnace working?

Customer: replied 3 years ago.
No. All the fans and blowers are doing fine, starting and stopping in the right sequence. But there isn't any gas being burned. I may have to get the local HVAC people out here to check out the furnace. It may have it's own problems.

Yes, one of the Hvac technicians just sent me a message stating that the problen is most likely in the furnace.
Tommy Tesla and other Electrical Specialists are ready to help you

Related Electrical Questions