Your furnace has a blower on it that circulates warm air through the ducts. When there's a malfunction, the blower may not turn on or it may not turn off. A few things can cause one of these problems, and until the problem is found and fixed, your home won't have heat. Here's a look at some malfunctions that affect the furnace blower and repairs that could be needed.
1. The Control Board Is Bad
The control board in your furnace sends power to all the parts, including the blower motor. If the control board goes bad, power can't get to the motor to trigger it to turn on. The solution to this malfunction is to replace the control board with a new one.
The control board can also fail in such a way that the motor gets a continuous supply of power. In that case, the blower motor will run continuously. This also requires the furnace repair technician to put in a new control board.
2. The Blower Motor Has Failed
If your blower makes noises when it tries to start, that could be a sign of bad bearings in the motor. When the bearings go bad, the motor needs to be replaced. Also, when a blower motor burns out, it has to be pulled out and replaced with a new one. The furnace repair technician can verify the problem is a bad motor by testing it with a multimeter.
3. The Thermostat Has Gone Bad
Thermostats have control boards in them that signal the blower motor to turn on and off. A bad thermostat can affect your furnace by making it run all the time or by keeping it from starting. Rather than replace the control board, the repair technician may replace the entire thermostat, so you'll have a chance to select a newer thermostat with more modern features if you want.
4. There's A Power Problem
Check the switch on your furnace to make sure it's on. If the switch is off, the fix is simple. Just flip the switch on and see if your furnace starts up and the blower runs. That will save a call to the furnace repair company.
The power problem might also be with the circuit breaker. Check your electrical panel for a flipped circuit. Flip the breaker all the way off and then all the way on to see if that restores power. If not, you'll need a repair technician to troubleshoot the electrical system in your furnace to find the problem.
Contact a furnace repair contractor to learn more.