Maintain your furnace with fresh filters and seasonal tuneups

While homeowners can handle changing filters and humidifier pads, and installing carbon monoxide detectors, experts say it’s best to leave other furnace maintenance to licensed and insured contractors.


METRO DETROIT — As winter approaches and the air grows chill, homeowners are turning up the heat and thinking more about furnace maintenance. Experts say there are several things to keep in mind to get the most out of your furnace — from the filters you use and how often you change them, to the tuneups that professional contractors can perform in order to keep things running smoothly.

A dirty furnace filter can cause problems, but it’s simple enough for homeowners to replace them on their own. Fresh furnace filters can be purchased at home improvement stores. Each is rated by their minimum efficiency reporting value, or MERV — the higher the MERV, the denser the filter. Simpler models should be changed every three or four months, while higher-density filters should be changed every six to 10 months, although the recommended schedule can change from model to model.

Both lower- and higher-MERV filters have their pros and cons. Higher-MERV filters collect more dirt but restrict airflow, which can sometimes damage the motor or cause the furnace to overheat and ruin the heat exchanger. They can also cause the furnace to work harder, driving up your energy bill. On the other hand, lower-MERV filters allow for increased airflow but may not collect as much dust.

“The lower-MERV filters will need to be changed more often,” said Marcus Piwonski, owner and general manager of Hoover Electric Plumbing Heating & Cooling, in Troy. “This depends on other factors, too, like whether your ducts are clean, how often you open the windows and whether there are pets in the home. … Usually, the wider the filter, the longer span you get to change the filter.”

Dave Tapling is the operations manager at Aladdin Heating and Cooling in Warren. He agreed that environmental factors play a role.

“I’d say, realistically, unless there are a lot of avenues for dust and dirt to collect in the home, that we recommend replacing filters twice a year, but if you have bad allergies, maybe change them four times a year,” Tapling said.

Changing the filter is also important because a clogged filter can cause the coil to freeze, which in turn can cause water to leak and pool up, even shorting out parts of the furnace — newer furnaces are more sensitive to that issue. In addition to changing your filters, consider replacing the humidifier pad that puts moisture in the air passing through the furnace.

It’s also recommended to install carbon monoxide detectors to monitor for poisonous gas emanating from the furnace. Carbon monoxide is odorless, so a detector is necessary to alert homeowners to its presence. Like filters, detectors are available at home improvement stores.

Also check the vents and PVC pipes for any loose connections, holes or signs of rust, as these can lead to gas leaks. A cracked heat exchanger can also leak carbon monoxide.

A professional can help spot these and other issues. While homeowners can handle changing filters and humidifier pads, and installing carbon monoxide detectors, experts say it’s best to leave other furnace maintenance to licensed and insured contractors. During a tuneup, burners are cleaned and adjusted for proper combustion, improving efficiency.

A full inspection and tuneup by a professional every one or two years can cost $60 to $90, but it pays off by lowering utility bills and maintaining the warranty on your furnace. Inspections can also sometimes qualify you for a rebate from your utility company.

It’s also recommended to check the furnace ignitor and the thermostat batteries once a year. When nobody is home, the thermostat can be dialed down to save power, but you shouldn’t lower the thermostat more than seven or eight degrees below normal temperatures. Allowing your home to grow too cold will strain the furnace when it tries to warm the home later, which will waste energy.

Furnaces can last 15-25 years, typically falling around 20 years, but routine maintenance and regular changing of filters can prolong their lifespan. If there are burning smells or strange sounds coming from your furnace, there may be an issue. The furnace running too long or repeatedly cycling on and off may be another sign of trouble. The heat exchanger and motor can also wear out with age.

Piwonski said a furnace checkup is especially important for anyone whose basement collected water over the summer.

“Hoover offers the ability to go through and balance the air flow in the home and seal the ductwork so there is less hot and cold spots in the home, along with minimizing air loss that will lower the furnace’s efficiency,” Piwonski said. “Customers should keep their fan running if they have a variable speed furnace, so air is more circulated in the home. Lastly, keeping the humidity 35%-40% in the home will make for a more comfortable home, less call for heat, and also keep you from getting allergy problems.”

The furnace maintenance business tends to ebb and flow with the fortunes of the economy — when the economy is slow and money is tight, more people tend to defer maintenance. But Tapling said that business has been steady, and it may have to do with more people working from home.

“I would say it’s been the opposite of slow — since coming back from the pandemic, we have been nothing but steadily busy, with little to no downtime,” Tapling said. “I think it has to do with people being in their homes more, so they don’t put off the issues they did when they were going to the workplace.”

The experts agree that the best time to have an inspection done is when the weather changes, making now a prime time for a look-over and tuneup.

“A safety inspection should be done once in the heating and once in the cooling season,” Piwonski said.   

Tapling agreed, adding that “since appointments tend to fill up quickly around those times, we also recommend calling shortly before each season.”

Hoover Electric Plumbing Heating & Cooling is located at 1871 Woodslee Drive in Troy and can be reached by calling (248) 277-5967. Hoover offers zero-dig sewer solutions, same-day repairs at no extra charge, $89 sewer clearing, and $59 furnace or air conditioning safety checks.

Aladdin Heating and Cooling is located at 26969 Ryan Road in Warren and can be reached by calling (586) 758-5900. Aladdin also offers boiler maintenance in addition to its other services.