Tips for Properly Wiring Your Furnace Blower

Person working on wiring a furnace
  • .5-1
  • Intermediate
  • 10
What You'll Need
Drywall anchors
Masking tape

It is easy to wire a furnace blower without any professional help, which helps save money. Here are some tips to properly wire the furnace blower.

Step 1 - Turn off the Electricity

It is important to first turn electrical power off, which is being provided to the furnace blower through the circuit breaker box or the power panel. Identify the right circuit breaker and switch it off. After it is done, cover the switch with some masking tape so it is not turned back on, while wiring the furnace blower.

Step 2 - Disconnect the Wiring

Remove the wiring meant for power supply from the furnace blower’s backside. Also make sure the wires do not fall back into their place in the wall. To avoid this, wrap the wires around a pencil so they cannot pass through the hole meant for the exit and the entry. In case there is no color code for the wires, they should be marked so they can be attached to the right terminal.

Step 3 - Attach the New Wires

Man working on a furnace

While connecting the new wires, be careful to make the right connections. Make sure that the different wires that usually connect to the fan blower and the air conditioner are properly attached. Usually, connect the green wire to a terminal marked “G”. Sometimes, the terminal for the green wire is also green in color. The green wire is typically used to offer power for operating the furnace fan blower. Then there is the terminal marked “Y”, which is used to attach the yellow wire. This particular wire is used to connect to the air conditioning facility.

Step 4 - Replace the Mounting Plate

When the mounting plate has to be replaced, there is no point in using the holes that were used earlier. This is because these holes may have become loose now. Installing the plate in these holes may prove to be hazardous. In case no studs were used to install the furnace blower on the wall, use drywall anchors for securing the furnace blower in a proper manner.

Some Important Things to Remember

Always check the wiring going to the furnace blower is smaller in size than the house wiring used to connect to the electrical outlets in the rest of the house. In case the wires that connect to the furnace blower are as large as the outlet wires, you may have to replace the entire length of wires right from the main power source of the house to the furnace blower. Hire the services of a professional electrician to adjust the length of the house wiring.