How to Install a Programmable Thermostat

Learning how to install a programmable thermostat will save you money because it will help reduce the amount of energy that your heating and cooling system is using when you’re not home.

Installing a programmable thermostat is actually a relatively easy DIY project that you can complete in thirty minutes or less.

You’ll need the following tools:

  • Masking tape
  • An electrical wire tester
  • A marker.
  • A screwdriver.
  • A bubble leveller.
  • A drill with a 3/16″ bit.
  • Plastic screw anchors.
  • A hammer.
  • A programmable thermostat with the Energy Star label.
  • Batteries (see thermostat box).

Once you’ve gathered your tools you’re going to locate your existing thermostat. After you’ve found it, go to your circuit breaker.

Turn off the power to both your furnace and your AC. Your thermostat controls both, so this is very important.

Net, you’re going to remove the cover from the old thermostat. Remove the old thermostat from the wall but don’t take the wires out of their connections yet.

Do stop to test the wires to make sure that no power is flowing to them.

You’re going to see different letters and numbers next to the screws by each wire. You might see, for example, “G”, or “R”, or “2.”

Installing thermostats isn’t quite the same as installing outlets. There’s no standard color code that you can use.

That’s why you’re going to need to use little bits of marked masking tape to mark each wire with the corresponding letter. If a wire is currently connected to G, mark it G.

Once you’ve got all the wires marked you can disconnect the screws and the wires. Make sure they don’t slide back into the wall!

Separate the front of the new thermostat from its base. You’ll want to position the base against the wall, pulling the wires through the center opening.

Use your bubble leveler to line up your base. You don’t want a crooked thermostat!

Once you’ve got everything lined up you’ll need to mark the mounting screw holes with a pencil. This will allow you to drill your holes in exactly the right spot.

Remove the base and drill your holes. Add the screw anchors. You’ll need to use a hammer to get the anchors in, but you don’t have to get too vigorous with it.

Now put the base back and mount it to the wall. Don’t forget to pull the wires through the opening once more.

Once you’ve got the base mounted you can start attaching the wires to the proper connections.

Once you’ve got each wire attached to the right terminal you’re going to want to install batteries into your control unit. Then press the reset button on the unit and mount the unit on the base!

You’re done! Add the unit to the base and restore the power.

For a project like this, it’s probably easier to watch a video to see how to install a programmable thermostat:

Remember, if you’re not 100% comfortable with an electrical project you shouldn’t do it. Call a qualified electrical contractor instead.

If you live in Hillsborough, Pittsboro, Wake Forest or anywhere else in the Raleigh metro area then you can always call us. We offer free estimates and we’re available 24/7!

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