In Repair & Maintenance

How to Install a Programmable Thermostat

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I have ceiling heat. While ceiling heat is definitely not the most efficient method of heating a house, it does not have to be done manually anymore so I decided to install a programmable thermostat. You can get a similar one here. For more on energy efficiency and money savings, check out making your home greener and vampire energy and smart plugs. Read on for a step by step guide on how to install a programmable thermostat to make your home greener and save you not only electricity but also money.

Cadet programmable thermostat
My chosen new thermostat

Turn off old thermostat and remove faceplate

Old thermostat on
Old thermostat
Old thermostat off
Old thermostat turned off
Old thermostat wo faceplate
Old thermostat faceplate removed

Turn off the old thermostat and remove the faceplate. Every thermostat is different but there are a few basic ways to remove the faceplate. A flathead screwdriver pried mine off. Some are held on with set screws on the perimeter of the thermostat.

Turn off the breaker

First and foremost: even if you think the breaker is off, double check for power!! Use this tester from amazon.

breaker box on
Breaker box with all breakers on
breaker box off
Breaker box with main breaker turned off

Turn the breaker off to the thermostat that you are changing out. If you look at my photos, you’ll see that I flipped the main breaker. Since my breaker box is poorly labeled, this is the safest way to make sure that the power is off to what I’m working on. You never know if your box is connected properly to your breaker and it is always best to be safe rather than get a VERY painful shock.

Remove the old thermostat and pull wires out

Exposed wiring once thermostat is removed
My exposed wiring

I unscrewed two screws on the top and the bottom of the thermostat to remove my old thermostat. The wires can be gently pulled out of the box once these screws are removed but be very careful not to force anything in case your wires are old and brittle. Remove the old wire nuts and evaluate what you have for wiring so that you can evaluate how to wire the new thermostat.

Determining new wiring

Basic wiring diagram from original wiring
The original wires going into my box

You need to determine how your new thermostat will wire into your old space. If you are lucky, they will be similar enough to be able to use the old one as a roadmap. Unfortunately, my old thermostat was a single pole (2 wire) while my new programmable thermostat was a double pole (4 wire) set up. First, I had to determine which were the line and which were the load wires.

Simply, the line wires are where the power is coming from. The load wires are where the power is going to after the new thermostat, which acts as a switch. While the incoming power lines had a classic black and white wire, for the hot wire and neutral wire the load wires were both red. I determined that there was no hot and neutral wire to my ceiling heat wires. Once all of this was determined, I only had to follow the wiring diagram included with the new thermostat.

Wire the new thermostat and program

New and installed thermostat
the thermostat all installed and working

Once the proper wires are connected with the included wire nuts, gently push the thermostat back into the box. Make sure that the wires are gently bent back in or your wire nuts may come loose. The new thermostat is connected with two included screws into the box and the faceplate is connected. The new programmable thermostat had very easy to follow in order to set it and I had it done in only a few minutes.


I love my new thermostat. While it was unfortunately difficult to install due to some crazy wiring questions, I have not regretted installing it for a single moment. The thermostat happily programs in different programs for each day so that it can account for my personalized schedule. Also, I can set each preferred temperature to my personalized setting so for those who find they don’t want it as warm or as cool as others will all be happy. All said and done, now I want this thermostat in every room of my house.