2 Malfunctioning Parts of a Furnace You Need to Replace, Not Repair

Furnaces are low maintenance additions to your home but low maintenance does not equal maintenance-free. Minor furnace problems like dirty evaporator coils are diagnosed by inefficient cooling and a visual inspection and solved with a simple cleaning solution. Major furnace issues such as refrigerant levels need to be tended to by a heating repair technician.

There are also some problems that occur that will always require replacing the failing or failed part. Attempting to repair these parts either doesn't work or can pose a danger to either the system and its surroundings. A failed fix would leave you with the same, worsening problem as you had before the repair attempt.

So what are the malfunctioning parts of a furnace you need to replace instead of repair?


A furnace has two capacitors, which are devices that help the system's electrical supply in some way. The start capacitor kicks in when the system is powering on following your thermostat signal. This capacitor ensures that the system has enough steady power to properly begin its heating cycle.

The run capacitor picks up where the start capacitor leaves off. The run capacitor ensures that the heating cycle maintains a steady electrical supply so that the system doesn't overheat or short out.

Capacitors can start to fail, which means the unit will either cycle on or off too fast or fail to cycle on at all. You can test the health of the capacitors if you have a multi-meter with the capacitor testing setting. Or you can call out an HVAC tech to test the capacitors.

Either way, there is no way to sufficiently fix a capacitor and leaving the failing piece in place will just continue to worsen your unit's problems.

Blower Fan or Motor

A motorized blower fan in your furnace is how the cool air from your home gets into the furnace, passes through for heating, and then is pushed back out the vents to warm your home. A problem with either the motor or the fan, or both, can interrupt that system and leave you shivering.

A problem with the motor needs to be diagnosed by an HVAC technician but will result in the need to replace the motor. Repairing would only be a shaky, temporary fix and installing a new motor can greatly improve the efficiency of the unit.

Blower fan blades can become bent or broken, which definitely requires replacing the fan portion, though you can leave a healthy underlying motor in place. The fans are too delicate to bend back out and even microscopic breaks can result in pieces of metal flying off when the fan is running.

To learn more about how to solve these and other issues with your furnace, visit resources like http://www.alliedairheat.com.