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 airheatman Your Own Question
airheatman
airheatman, HVAC Technician
Category: HVAC
Satisfied Customers: 8327
Experience:  Furnace, A/C and heat pump specialist.
16514686
Type Your HVAC Question Here...
airheatman is online now
A new question is answered every 9 seconds

I just replaced both Honeywell PRO TH3000 Series thermostats

Customer Question

I just replaced both Honeywell PRO TH3000 Series thermostats with Honeywell RTH2510 Series. One thermostat is functioning properly. The other one did not. I put the PRO TH3000 series back on. It now does not trigger the AC.
Submitted: 2 years ago.
Category: HVAC
Expert:  airheatman replied 2 years ago.
Hello. My name is ***** ***** I'll do my best to help. Let's get started and see what we can do.Do you have two systems or just one system with 2 thermostats?
Customer: replied 2 years ago.
2 zones. One zone is a Goodman and is operating fine. The other zone is a newer Carrier and is the one that is not being triggered by the thermostat.
Expert:  airheatman replied 2 years ago.
OK if you have 2 zones but only one system, I will open to other experts as I am not that familiar with the zone control.
Customer: replied 2 years ago.
I am not sure what you mean by one system. I have two furnaces in the house and two a/c units/fans outside. I think they are two different systems. Two different circuit breakers.
Expert:  airheatman replied 2 years ago.
OK if you have 2 thermostats and t systems, this is good.(not a zoned system).Did you turn off power before removing old thermostat? If not we may have a blown fuse (auto type) in furnace if wires touched.
Customer: replied 2 years ago.
Yes. Swtiched off both circuit breakers and replaced both thermostats. Then switched on both circuit breakers.
Customer: replied 2 years ago.
Then, switched both breakers back off to put the original Honeywell back on. Then, switched on both breakers.
Expert:  airheatman replied 2 years ago.
OK we may have a wire in wrong place on new stat. Lest go to furnace first and see if there is a small fuse on furnace control board in blower compartment and check to see if it is blown,,We will go from there.
Customer: replied 2 years ago.
What tools will I need? Tools are in the garage. Furnace is in the attic. And, I need to get an 8' ladder out, too.
Expert:  airheatman replied 2 years ago.
If gas furnace. usually won't need tools to check fuse as panels slide off. Take a 5/16 nut driver just in case yours hs screws. Control board is going to be in blower compartment.
Customer: replied 2 years ago.
I am up here. The front appears to have a knob, but when I turn it, the front plate does not come off.
Customer: replied 2 years ago.
Disregard. Just came loose. What am I looking for?
Expert:  airheatman replied 2 years ago.
Mounted on blower housing should be a control board.On that board look for a 3 or 5 amp auto fuse.Remove fuse and see if it is burned.
Customer: replied 2 years ago.
I do not see anything resembling an auto fuse anywhere.
Expert:  airheatman replied 2 years ago.
Can you give me model on furnace? It will be on a label i burner compartment
Customer: replied 2 years ago.
58cva070-12
Expert:  airheatman replied 2 years ago.
Check link below and tell me if this is your board.If so fuse is a purple 3 amp.
http://i.imgur.com/pKP74Wg.png
Customer: replied 2 years ago.
I do not see that at all. I think I will have to call someone out. Thank you for your help.
Expert:  airheatman replied 2 years ago.
I understand. THis is going to be mounted to blower housing.May have a cover over it to protect from dust.
Let me ask you a question. Do you remember what wires went where on old thermostat and what you connected where on new thermostat?
Expert:  airheatman replied 2 years ago.
Did your old thermostat have a wire to C terminal and if so, what did you do with it on new thermostat?
Customer: replied 2 years ago.
Yes to the C; it was a blue wire. No C on the new thermostat. Wrapped the end in electrician's tape, per the installation instructions and did not attempt to hook it up. Upon reinstall of the old thermostat, put it back in the slot it came from.
Expert:  airheatman replied 2 years ago.
OK if you wish to continue, let me know.Below is a link showing the location of board.Fuse we want to check is plugged into the board as shown in previous post.
http://i.imgur.com/J2rykSP.png