The Purpose Of A Furnace Blower Motor Capacitor And How To Tell If It Needs To Be Replaced


If the blower in your furnace doesn't spin, there won't be any hot air blowing from your registers when the furnace kicks on. Your house will cool down quickly, and if it's freezing outside, you might have a heating emergency on your hands. A common problem that keeps the furnace blower from working is a bad capacitor. Here's a look at how the capacitor works, how to tell if it's bad, and how it is replaced.

The Purpose Of The Blower Motor Capacitor

A capacitor works like a battery. It holds an electric charge that's sent to the motor when it first kicks on. This extra boost of power helps the motor turn the blower cage to start it up. Without that added power boost, the blower motor won't be able to start the blower fan and there will be no hot air blowing through the ducts to warm up your house.

When To Suspect The Capacitor Is Bad

If your furnace kicks on but the fan doesn't start, that could mean there is a problem with the fan, motor, or capacitor. If you hear a humming sound rather than the fan turning, that's a sign the capacitor is bad. A heating repair technician can test the capacitor further to pinpoint the problem.

How A Capacitor Is Replaced

When the capacitor goes bad, it has to be replaced, just like a bad battery is replaced. The capacitor is a fairly inexpensive furnace part, so most of the cost of the repair is for expertise and labor. However, paying a heating repair company to replace a bad capacitor is usually the best idea because a capacitor holds an electric charge even with the power shut off. You could get a serious electrical shock if you don't handle a capacitor carefully.

The capacitor is usually strapped to the housing of the blower. It's shaped like a large battery. The repair technician discharges the electricity in the capacitor first and then removes it from the strap that holds it in place. The new capacitor is then placed in the strap and the strap is screwed back to the housing to hold the capacitor securely. Wires are connected to the ends of the capacitor and the operation of your furnace is tested. If the only problem was the capacitor, the blower should start right up once the furnace kicks on.

If you remember to have your HVAC serviced on schedule, you can reduce the risk of unexpected problems with the blower in the middle of winter when your home needs heat to keep you warm and to keep plumbing from freezing. Reach out to a heating repair professional if you suspect your capacitor is broken. 


18 January 2021

Getting Help With Your Troubled Air Conditioner

Does your air conditioner smell, make loads of extra noise, or fail to cool your home? If you have noticed any of these problems, there might be issues with your air conditioning unit. Fortunately, you don't have to let a bum system make your home stuffy and uncomfortable. Professional heating ventilation and air conditioning contractors can snap your AC unit into shape in no time. By carefully checking your condenser and evaluating your refrigerant levels, the experts might be able to dramatically improve the cooling capacity of your home unit. Read here to find out how to spot problems before they make your space uncomfortable.