6 minute read • Graham Lumley • Last update November 2024
When temperatures drop, a well-maintained furnace can make all the difference in keeping your home comfortable and safe. Regular furnace maintenance not only improves your heating system’s efficiency but also helps extend the lifespan of your unit, saving money on repairs and energy bills in the long run.
In this guide, we’ll cover everything you need to know about home furnace maintenance and provide a handy furnace tune-up checklist for both forced-air and electric systems.
The guidelines regarding furnace maintenance and how to service a furnace vary depending on the specific set-up of your HVAC system. Here’s a quick overview of the most common configurations:
All variations benefit from regular maintenance, and even a new furnace requires periodic checks. Once you know your heating system type, you can apply the correct furnace cleaning techniques to keep it running efficiently and extend its lifespan.
Even the most energy-efficient furnaces need a bit of TLC from time to time. Full furnace inspection and servicing should only be conducted by a trained professional. However, cleaning a furnace yourself is possible, provided you have the correct tools and equipment. Here’s a quick list of what you’ll need for DIY maintenance:
With these tools at the ready, you can easily tackle basic home furnace maintenance in preparation for heating season.
Forced-air models are among the most common furnace systems found in homes. They use natural gas, oil, or propane to warm air and distribute it throughout your home via a network of air ducts and vents. Below is a maintenance workflow to keep your forced-air system in top shape. We’ll highlight variations between oil, propane, and gas furnace maintenance where relevant.
Look for signs of leakage. Oil leaks are usually obvious, while gas systems may emit hissing sounds or the smell of propane.
Always shut off the fuel supply by closing the oil or gas valve before starting any maintenance.
Ensure it’s functioning properly and set to the desired temperature. If the thermostat is inaccurate, consider recalibrating or replacing it.
A dirty furnace filter restricts airflow, negatively affecting air quality and raising energy costs. Change filters every 90 days, or more often if you have pets or allergies.
Open the blower door and remove dust and debris using a soft brush and shop vac. This will maintain proper airflow and efficiency.
Turn the furnace on briefly. A healthy flame should be blue. A yellow flame indicates a gas leak or lack of oxygen in the combustion chamber. After checking the flame, close the oil or gas line again and gently clean all parts of the burner assembly and burner cover.
Carefully examine the heat exchanger for cracks or corrosion. If you’re conducting oil furnace maintenance, you’ll also need to look for soot buildup or oily residue from the combustion gases and clean them away.
You can only clean your furnace’s flame sensor thoroughly once it’s removed. The manufacturer’s guidelines should show you how. To clean a furnace flame sensor properly, use a soft brush and electrical contact cleaner. The goal is to remove built-up dirt—not to make it shine like new.
Electric furnaces require less frequent lubrication. However, oil and gas furnaces often have motor bearings or other components that need lubrication to reduce friction and extend their lifespan.
Check belts for signs of cracking or fraying and ensure proper alignment. Oil furnaces sometimes have additional belts in their blower system, so there may be extra areas to inspect.
On gas set-ups, test the ignition system (either pilot light or hot surface igniter). On oil systems, listen for unusual sounds coming from the ignition transformer.
Clear blockages in the air vents and return air ducts that may prevent your system from operating at peak efficiency. If your home has a complex system, you may need to invest in professional duct cleaning.
Cracks or holes can allow exhaust gases to escape, posing a serious health risk to your family. If you spot any damage, you should schedule a professional furnace tune-up and service immediately.
Your detector should be checked regularly as your primary warning for gas leaks. Proper positioning is also essential. It should be close enough to detect issues but not so close that it gives false alarms when your furnace is starting up.
If your furnace short cycles (turns on and off repeatedly in short bursts), your home is unlikely to reach the desired temperature, affecting comfort.
The shut-off function should automatically stop your furnace if there’s a problem with the heat exchanger, hot surface igniters, blower fan, or other critical components. Testing the shut-off ensures everything powers down correctly.
Electric furnaces are a popular option for homes without access to gas lines. They draw in cool air and use heated coils or elements to warm it and distribute it back through your home. While they generally require less upkeep than fuel-burning models, annual furnace maintenance is still essential to ensure efficiency. Here are the steps to incorporate into your HVAC maintenance plan.
To remove electrocution risk, always ensure the power switch is off before touching any electrical connections or cleaning the furnace.
Make sure the thermostat is responsive and accurately regulating temperature. If there’s a lag or inconsistency, consider recalibrating or upgrading.
Open the furnace doors and remove and inspect the filter. Either clean or replace it to ensure your system won’t just blow dust through the vent covers when it’s in operation.
As with oil, gas, and propane models, regular furnace maintenance involves using a shop vac or a soft brush to remove dust from the blower compartment and blades.
Because electric furnaces don’t use fuel, there’s no combustion chamber door to open. However, you’ll still need to check the heat exchanger for cracks or wear that could impact performance.
Moving parts like blower shaft bearings and motor bearings require lubrication to reduce friction and prolong their lifespan.
Look for belts showing signs of cracking, fraying, or general wear and tear. Worn belts should be replaced to prevent mechanical issues.
Regular furnace vent cleaning removes dust and debris from the immediate airflow path. Meanwhile, furnace duct cleaning reaches deeper into the system. Depending on your duct network, this may be a task for a qualified HVAC technician.
Short cycling signals an issue that needs attention. A standard cycle is usually 10–15 minutes. If your furnace shuts off in less than five minutes, you should schedule a complete HVAC service.
Verify the safety shut-off switch is functioning properly so your furnace will automatically turn off in the event of a problem.
Learning how to clean a furnace yourself can save money. However, just as with other HVAC components, like your air conditioning units, professional furnace inspection and servicing are essential for ensuring safety, efficiency, and long-term performance. Here are answers to some common questions.
How often should you service your furnace?
Ideally, your furnace should be serviced at least once a year to catch any problems early and ensure everything is functioning properly.
When should you call a professional to schedule furnace maintenance?
The best time to schedule maintenance is early fall, just before the cold season arrives. This allows enough time for any necessary furnace repairs and adjustments before it’s in regular use.
What are the signs a unit might need professional maintenance?
In addition to regular annual servicing, you should call a professional if you notice any of the following signs:
How much does professional furnace maintenance cost?
The exact cost will vary based on your area and the required services. HVAC technicians typically charge similar rates to electricians and plumbers. On average, furnace repair bills range from $150 to $300.
A clean furnace typically leads to reduced energy bills, and we hope you find these furnace maintenance tips helpful in achieving just that. But there are plenty of other ways to save as well!
In addition to regular furnace maintenance, consider upgrading to ENERGY STAR-rated equipment, sealing windows and doors to prevent heat loss, and setting your thermostat to an optimal temperature.
At BKVE, we’re committed to helping homeowners save on energy costs with affordable electricity plans tailored to your needs. Enter your zip code today to find the right plan for you.
