Allergies and AC filters

How To Replace A Blower Motor On Your Gas Furnace

You will know your furnace blower motor is going bad when you start hearing loud squeaking sounds coming from it. The blower will usually stop running a short time later. The warm air of the furnace will then stop circulating throughout your home. You will need to change the blower to get everything back to normal. Here is how you can replace the blower on a typical gas furnace.

You Will Need:

  • Small Crescent Wrench
  • 3/8" Socket
  • Socket Wrench
  • Small Phillips Head Screwdriver
  • Utility Knife
  • Masking Tape
  • Marking Pen


  1. The first thing you want to do is turn the power switch off to the furnace (put some masking or duct tape over the switch to prevent someone from accidentally turning it back on).
  2. You'll need to remove the bottom panel on the front of the furnace to gain access to the blower.
  3. Remove the wires going to the humidifier and thermostat. Then carefully cut the plastic harness holding the control wires together.
  4. Remove the screws on the support bracket holding the blower in place on the furnace. Slide the motor out of the furnace and onto the floor – be careful, the blower motor is heavy.
  5. Disconnect the motor wires from the control board. Pay special attention to how the wires are connected to the control panel so you know where they go when you reconnect the new motor. Disconnect the wires going to the capacitor.
  6. The blower wheel is held in place to the motor shaft using a set screw. You can use a small crescent wrench to remove this screw.
  7. Flip the blower over and remove the mounting bracket screws using a 3/8' socket wrench. The motor should lift right out of the blower – make sure you mark where the motor is situated on the bracket using a marking pen. Remove the screws holding the motor bracket together and lift the motor out.
  8. Make sure you have a motor that is specifically designed for your furnace. Set the motor into the mounting bracket and tighten the screws holding the bracket together – make sure the motor is lined up with the markings you put on the bracket. Reconnect everything in the reverse order of what you did to get the blower motor out of the brackets and furnace.

If you feel you need assistance replacing a blower motor, you should call a heating contractor like Krewson-Sweeney Oil Inc right away before your house gets really cold inside.