Furnace maintenance guide
By Allstate
Last updated: January 0001
Key points
- Regular furnace care (e.g. changing filters, cleaning components, checking safety controls) improves efficiency and lowers heating costs.
- Annual professional inspections help detect issues early – ensuring safety and preventing costly breakdowns.
- Getting maintenance done in the early fall gives you time to fix any problems before it gets really cold.
Your furnace is one of the most important pieces of equipment in your home. It produces the warm air that keeps your house heated during the cold months and it works with the air conditioner to cool your house in the summer. The good news is that furnace maintenance is often relatively easy.
Here's what you need to know about caring for your furnace:
Furnace maintenance you can do
There is some routine maintenance you can do to help keep your furnace running safely and efficiently.
Inspect and change the air filters
ENERGY STAR suggests checking your furnace's air filter every month and replacing it when it looks dirty. A dirty filter can slow air flow and reduce efficiency, and the furnace may stop working if too much dust and dirt builds up inside. At a minimum, change the filter at least every three months, says ENERGY STAR.
Tip: Filters work best when they fit snugly — so make sure you're buying filters that are the right size for your furnace.
Keep vents clean and clear
Before you turn on your heating system for the season, remove vent covers from the floors, walls and ceilings around your home. Vacuum the covers and the opening of the ducts, says This Old House. Dust, pet hair, small objects (including toys) and even food can collect there. This can block air flow and cause your furnace to work harder.
Tip: Sealing leaky air ducts with metal tape or duct sealant can help improve the efficiency of your heating system, says ENERGY STAR.
Install a carbon monoxide detector
As furnaces burn gas or oil to heat your home, they produce carbon monoxide, says the Centers for Disease Control and Prevention. Install battery-operated or battery-backup carbon monoxide detectors on every level of your home to help alert you if your furnace is leaking this dangerous, odorless gas into your home. Also, check the detectors regularly to help ensure they are in working order.
Tip: Change the detectors' batteries at least once a year. You can use the end of daylight saving time as a reminder to do this task.
Why is furnace maintenance important?
Proper furnace care can help keep you safe, save you money, and ensure your system runs smoothly through the winter.
Furnace maintenance can help keep you safe
For homes with a fuel-burning furnace, regular maintenance helps residents avoid or address carbon monoxide (CO) problems, according to the Centers for Disease Control and Prevention (CDC). Carbon monoxide is an invisible, odorless gas, and it can lead to severe illness or death when it begins to build up in a home. Because people can't see, smell or taste CO, the CDC recommends having your furnace inspected every year and promptly address any issues. Additionally, the organization notes homes should have properly working CO detectors.
Furnace maintenance helps you avoid major breakdowns
Routine, proactive maintenance helps homeowners locate and address minor problems before they turn into significant issues that often cost much more to repair, according to Genz-Ryan Heating, Cooling, Plumbing & Electrical. By addressing conditions before they arise or before they deteriorate more, homeowners can minimize the risk of major breakdowns. After all, you don't want to be left without heat during the coldest part of winter.
Furnace maintenance can save you money
While furnace maintenance does cost some money upfront, it might help you save in the long run. Solving issues early can help avoid more significant breakdowns and costly repair bills later. Additionally, sticking to a regular maintenance schedule can lower your heating and cooling expenses by 10% or more and extend the lifespan of your equipment, explains the U.S. Department of Energy.
What are signs that your furnace requires maintenance?
Here are some signs your furnace might need maintenance, according to Jacobs Heating & Air Conditioning:
- Your house isn't heating up, or it's taking longer than normal to heat up.
- Your energy bills have increased by a noticeable amount.
- You're hearing strange noises.
- Your furnace won't turn on at all, or it's cycling on and off more frequently than normal.
- You notice a yellow pilot light instead of the typical blue color.
While all these issues can indicate it's time to have your furnace serviced, some of them can be more urgent than others. For example, a yellow pilot light could indicate a carbon monoxide leak, according to Jacobs Heating & Air Conditioning. So, if you notice any issues at all, make sure to have a trained professional address them promptly.
Furnace maintenance you can do
Help keep your furnace running safely and efficiently with some basic maintenance.
Inspect and change the air filters
Check your furnace's air filter every month and replace it when it looks dirty, suggests ENERGY STAR. A dirty filter can slow air flow and reduce efficiency, and the furnace may stop working if too much dust and dirt build up inside. At a minimum, change the filter at least every three months.
Tip: Filters work best when they fit snugly – so make sure you're buying filters that are the right size and rating for your furnace.
Keep vents clean and clear
Before you turn on your heating system for the season, remove vent covers from the floors, walls and ceilings around your home. Vacuum the covers and the opening of the ducts, says This Old House. Dust, pet hair, small objects (including toys) and even food can collect there. This can block air flow and cause your furnace to work harder.
Tip: Sealing leaky air ducts with metal tape or duct sealant (not duct tape) can help improve the efficiency of your heating system, says ENERGY STAR.
Install a carbon monoxide detector
As furnaces burn gas or oil to heat your home, they produce carbon monoxide, says the CDC. Install battery-operated or battery-backup carbon monoxide detectors on every level of your home to help alert you if your furnace is leaking this dangerous, odorless gas into your home. Also, you should be checking your carbon monoxide and smoke detectors every six months to help ensure they are in working order.
Tip: Change the detectors' batteries at least once a year. You can use the end of daylight-saving time as a reminder to do this task.
Furnace maintenance for professionals
An annual tune-up by a professional is an important part of maintaining your furnace, according to ENERGY STAR, and it may help prevent costly furnace repairs down the road. A heating contractor will make sure that your thermostat is working correctly, the system is cycling on and off properly and will typically go through a series of checks and tasks, including:
- Tightening loose electrical connections
- Oiling all the moving parts
- Inspecting all gas connections
- Cleaning the burner
- Checking for cracks in the heat exchanger
Tip: Call the contractor before temperatures take a dive, ENERGY STAR says, or you may find it difficult to get on their busy schedule.
After you've done all that, listen for any signs of trouble when your heating system is running. If your furnace is squeaking, rattling or otherwise making noise, it may be a signal that a part has come loose, another cleaning is in order, or a sign that your unit needs replacing. If you notice any strange noises, call a professional for help.
How much does furnace maintenance cost?
The average maintenance cost for a furnace is $80-$300 according to Angi. However, these numbers can vary depending on where you live, labor costs, time of year and furnace model. Angi also notes that your costs could differ if you make a one-off service call or sign up for an annual service contract that includes a set number of tune-ups and potentially covers basic repairs.
Your furnace is key to keeping your home comfortable during the cold months. Taking care of these routine maintenance tasks can help keep your furnace in good condition so it can keep you cozy all winter long.