top of page

Can I install my own Programmable Thermostat?

Safely installing your new Digital Programmable thermostat in your Winnipeg home should not be something that gets your dandruff up!

Although there are exceptions to the difficulty involved with replacing a thermostat with a newer model, most of you that have ever replaced a light fixture or receptacle in the past should have no problem following the suggested tips here.

Before we get started with some instruction, the programing aspect will not be discussed here since each Manufacturer whether a Nest, Ecobee, Lyric, Honeywell, White Rogers or any other less known brand will have their own “language” that you will need to learn to properly configure any options and settings. Configuration can be key to even simple basic usage and of course more involved when whole house systems include Central a/c, Humidification, Ventilation (HRV) and Hybrid or Dual Fuel Equipment.

Note: Most older homes may not have a dedicated “C”(common wire) since older mercury or bi-metal style thermostats did not require a common to provide full control. Some of the newer “Power Stealing Thermostats can be set up to work with reduced functionality (no fan control) or be used with the risk of intermittent program or signal issues. To be safe and sure if your new Thermostat has a “C” connection you should use it even if it requires extra costs to run the extra wire.

The following tips are offered here for inspirational purposes only, and are not meant to substitute the manufacturer instructions that are included with your particular model.

1) Review your instructions included with the new thermostat. Even if you do not understand everything you are reading this is an important step. Some thermostats have a few options that are set by jumpers or switches that will help it work properly with your particular heating system. A typical such setting is one that selects GAS or ELECTRIC heat. Failure to select the proper setting can be avoided if you take the time to read the manual first. Most reputable manufacturers that sell thermostat models at "big box" stores will usually include a website or even a telephone number you can call if you need help. Almost always both the call and help are free.

2) Confirm the control voltage required for your system. Line voltage (120 or 240 volt) thermostats are mostly used on Electric baseboard or in a more commercial setting with Radiant or Unit Heater control. The wiring for these will be heavier (#14 or 12 gauge).

Chances are your Gas or electric furnace or boiler will use a 24 volt control system and have lighter/smaller wiring for connecting the thermostat (usually #18 gauge).

Warning: If you find that the wires are lighter than 18 gauge such as 22 Gauge Telephone cable there is a chance that your thermostat will fail due to signal losses.

3) Turn off the circuit at the main electrical power box.

If you are not 100% sure that you have the right circuit turned off, you should then turn off the main power switch. In either case you need to use a circuit voltage tester to confirm that the power is indeed off before you proceed.

4) Remove the front cover and control from your old thermostat. Look for a recessed lip around the sides or bottom of the original thermostat where you can grab and remove the faceplate and control board. The cover and control board on most models are just clipped on and will snap off. Be careful setting it aside as you may have to reinstall it if something goes wrong during the rest of the installation.


Remove the wires one by one and label them according to their current location. Most new programmable thermostats come with sticky labels that you can use to wrap around the wires that come out from the wall. If your package doesn’t contain any labels you can simply use masking tape and a marker or pen.

6) Remove the old base plate from the wall. Be careful not to let the wires fall back into the wall. They may be loose enough and disappear into the wall cavity and add time and frustration for you to fish them back out.

7) Install your new base plate. Most thermostat kits will include plastic anchors to use when new mounting holes are required. Depending on the model of Thermostat this may be the time to install the batteries. If not you will then be installing them on the thermostat itself.

8) Find the connection points on either the baseplate or thermostat and re-attach the wires based on matching up the labelled wires to their corresponding locations. This is usually the hardest part of the installation. There may be a lot of wires to connect with what may appear to be extra or a shortage of wires. If so, you will have to consult with the manufacturer’s instructions that will normally provide a conversion table for the intended use.

9) Install the front control panel or faceplate. Take note of the wires that you have used (R,G,Y,W,C…..). This may help you on the next and final step.

10) Restore the power to the system. Time to complete your reading in the program section of your manual. If the batteries are located in the thermostat module and not on the back plate, you can do the programing in the comfort of your chair and clip it onto the wall once you are done.

Warning: Most older thermostats have glass tubes that contain mercury. Be careful when handling and disposing of them.

Tradesman Mechanical at 975 Main St. in Winnipeg is registered as an official recycling station for mercury based thermostats. This service is offered at no charge.

26 views0 comments

Recent Posts

See All


bottom of page