Troubleshooting your furnace blower motor

A furnace blower motor is one of the most important components in your gas or oil furnace. Consider that the purpose of gas furnace is to warm the home, and realize that it is the blower motor that actually takes that heat and directs it from the very isolated, insulated furnace and in to the actual home. If you’re having problems with the blower motor, you’re not only left wanting for heating in your home, but you’re wasting energy as any gas you burn and heat your furnace creates that isn’t actually channeled in to the house that needs it is pointless.

Basic Troubleshooting

One of the most common problems is that the blower motor makes a humming sound. If this is the case, then the first thing you should do is turn off your motor and allow it to cool. When it has cooled down to a safe temperature, check the motor. Like with many devices that are in motion regularly, the humming could be the result of something as simple as improper lubrication.

Humming at Slow Speeds

When your furnace blower has warmed your house to the set temperature, it begins to run on a slower speed. This is a normal energy saving mechanism that the motor is supposed to employ. But if your blower motor slows down unusually and makes a humming sound when it has slowed down, it might be due to a fault in the capacitor and the motor.

Check your motors amperage draw using a tool that reads electrical current such as a multi meter and then check the rating on the plate of your motor to see how much is required. If the draw is more than the required amount, it’s an indication that your motor is working extra hard just to work normally. You will have to replace the motor and the capacitor. This problem in your blower motor may have been caused by dust and dirt in your filter. An unclean and blocked filter makes the motor work harder to push out air. Make sure you check and clean the filter regularly to avoid this kind of problem from recurring.

If your furnace blower motor hums when it’s switched on but at the same time does not actually turn, the capacitor may be damaged. This problem of getting a humming noise along with little to no spinning is very common with motors that do not have good quality capacitors. You should replace the capacitor with a good one and the blower motor will work smoothly. Once again, this may initially trace back to a simple blocked filter.

If your motor does not run even after replacing the capacitor, it is most likely that the unit overheated. You should reset the safety buttons located at the side of the unit.

Humming When the Blower is Off

This is usually caused by the wrong adjustment of the pilot light of your blower. Readjusting it to an appropriate level should solve this issue.

Humming When the Blower is On

If your gas burners are dirty, they will give out a low sound that may sound like something between a low rumble and a hum. Cleaning, adjusting or replacing them will make the irritating sound go away.

If you don't feel comfortable performing the diagnostic steps, please give us a call, so one of our trained technicians can make sure your system is running safely and efficiently. Self Heating and Cooling 678-909-6377

The flue on your furnace is designed to vent carbon monoxide and other gases made during the combustion process outside. If the flue is clogged or damaged, it can't do its job, and this puts you and your family at risk. Every vented heating appliance in your home should be inspected and cleaned regularly to prevent carbon monoxide poisoning.

Soot around your furnace is also an indication of a problem. Soot can build up to in your venting system and block it. If your furnace is vented through a masonry chimney, look for white residue on the brick. This is a sign that mineral salts are coming through the masonry because too much moisture is inside the chimney. Although flame color doesn't always mean the presence of carbon monoxide, a change in the color of your flame, such as blue becoming yellow, indicates that the level of carbon monoxide has increased, and this may be caused by a blocked flue.

A blocked or damaged furnace flue prevents combustion gases from escaping outside. Instead these gases are released into your home. Once inside, they recirculate, and then carbon monoxide becomes part of the air taken in during the combustion process. This increases the amount of carbon monoxide present. The cycle continues and can build up to deadly levels of carbon monoxide in your home.

Symptoms of carbon monoxide poisoning resemble the flu, without fever, in the beginning. If you or your family experience headache, nausea or vomiting, dizziness, fatigue, difficulty breathing or loss of consciousness, go outside your home immediately. If the symptoms lessen or go away but return once inside, you may have carbon monoxide poisoning. Open all doors and windows and turn off any combustion appliances. Seek medical attention. Have your furnace inspected and the flue cleaned immediately by a professional. Have carbon monoxide detectors installed in your home.

Your furnace needs to have its venting system cleaned every year. The buildup of particulates is not as significant as it is with a fireplace flue, but over time, they can reduce the efficiency of the flue. This is dangerous and can lead to carbon monoxide poisoning. Contact a qualified professional to have the venting system cleaned and inspected for damage or leaks even when the furnace appears to operate properly. Only a trained technician can detect blockages or buildup inside your furnace flue and correct the problem. Call Self Heating and Cooling to check your heating system and verify the flue pipe is working as it should.