Residential Furnaces: 5 Common Problems And How To Fix Them

Furnaces are at the heart of your home’s heating system. They heat the air dispersed into the supply vents and duct system. While most furnaces are located inside the house, they can also be found outside in some cases.

Several residential furnaces can be operated using natural gas, propane, electricity, and oil. Every option has its upsides and drawbacks, but most residential furnaces rely on natural gas because of its efficiency and low operational costs.

While residential furnaces can last for several years with proper use, it’s subject to wear and tear. Below are the most common problems owners will likely face and what to do to fix them:

1. Furnace That Doesn’t Seem To Work

There could be multiple reasons why a furnace doesn’t work. If you notice that the furnace isn’t blowing air or doesn’t heat at all, the culprit could either be a clogged blower or problems with power, the thermostat, the pilot light, or its primary source.

• Make sure your blower is free from blockages.
• Check the vents in your rooms and ensure they’re fully opened for proper airflow and heat.
• Check the electrical switch and make sure it’s turned on.
• Do the same for your breaker box.
• View your fuse box power switch. If you find that it needs a replacement, visit your nearest store.
• If this doesn’t work, check the electrical panel.
• If your blower displays a flashing light, call a technician to fix the problem.

As a precaution, ensure that your electrical system isn’t grounded and that your hands and surroundings are dry to avoid an electrical shock. Don’t attempt to fix any electrical problem; leave the work to professionals.

2. Weird Noises From The Furnace

Mechanical problems in your electric and gas furnaces may result in popping, rumbling, or rattling noises in your furnace. So are blockages in the burner or ducts. Rattling often indicates loose sections in the furnace while popping could signal ductwork issues.

A damaged blower belt can also produce a high-pitched sound if you turn on your furnace. Buy a new one and call a technician to replace the belt unless you’ve done it before. Meanwhile, scraping noises may indicate worn-out ball bearings, which enable the motor to work smoothly. If this happens, turn off the unit and call a technician to avoid serious problems.

3. Thermostat Problems

The furnace produces heat through a combustion chamber controlled by a thermostat. The burner creates flames to heat metal tubes and warms the air passing through the vents and ducts.

Thermostats can be sensitive, and several owners have reported malfunctioning thermostats as a common issue. An inefficient furnace, frequent cycling, and constantly running fans are three primary indications that your thermostat needs to be fixed or replaced.

In some cases, replacing thermostat batteries will do the trick. If not, remove the dust and debris in and around it. Check the manual to find the best thermostat setting to prevent frequent cycling.

4. Clogged Air Filters

Heating, ventilation, and air conditioning (HVAC) systems have built-in filtration functions. As such, air vents have filters to trap dust and other pollutants to ensure indoor air quality. With time, these accumulate, and air filters must be replaced to keep the system efficient.

A clogged air filter may lead to more severe issues like reduced heat and airflow, potential duct leaks, and damage to the system’s electric and mechanical sections. Your heat exchanger, which separates the flame from the air, may crack and make your unit unsafe. Replacing air filters every three months can help homeowners avoid costly furnace replacements.

5. Pilot Light And Control Issues

A faulty pilot control will make it challenging for your furnace to heat your living spaces. If your pilot light is flickering or displays an odd-colored light, it could mean the presence of drafts, clogs, and other issues with the furnace’s electrical or mechanical components.

If you suspect a draft is causing trouble in your furnace, check the windows and doors in your living space and close them. If this doesn’t work, try to turn off the system, including the gas valve, and wait for at least 15 minutes before relighting the pilot switch. Before re-igniting, ensure that your surroundings don’t smell gas or propane, which could indicate a gas leak. Evacuate immediately and inform the contractor or the local fire department.

Conclusion

As a homeowner, you can perform minor HVAC maintenance activities such as cleaning and replacing filters. If you have a background in electronics, you may check for issues but avoid fixing them as much as possible. Doing so can void the warranty and lead to more significant problems later.

Besides annual checkups, significant HVAC works such as furnace installation, repair, and replacement are best left to professional contractors as a simple mistake can become a severe problem.