The change of seasons is an excellent opportunity to arrange HVAC maintenance. To guarantee your heating system is ready to perform when you need it most, schedule a semi-annual system checkup for the fall.

According to the Building Efficiency Initiative, effective maintenance can extend the life of your system and save heating expenses by 5 to 40%. Use the checklist below to cover the fundamentals of getting your heat pump and furnace ready for cold weather.

1. Feel and Listen: A good starting point is to simply turn on the heating system and listen for strange noises. Warm air should be blowing from the registers. Locate the source of any noises and begin troubleshooting there.

2. Clean the Coils: Dust can accumulate on the evaporator coils inside the air handler, forming an insulating layer that reduces the effectiveness of your heat pump. To clean the coils, use a dusting brush and a shop vac. Make sure the drain pan beneath the unit is clean and that the drain stopper is clear of impediments, allowing condensation to run freely.

3. Recharge the refrigerant: The refrigerant that powers your heat pump is under pressure, and a slow leak can reduce the performance of your system. Follow the directions on your equipment to check the refrigerant level and recharge the system. If you have a leak, a UV dye kit might assist you in locating the leak and repairing it.

4. Inspect Ducting for Leaks: A visual inspection of your ductwork may show tears or loose connections. Turn on the blower fan and inspect every ductwork junction with a smoke match for drafts that displace the smoke column for a more thorough leak test. Small leaks can be fixed using duct tape and sealant, but larger breaches may necessitate a ductwork replacement.

While many professionals will offer to clean the dust from your air ducts, there is no proof that dirty air ducts affect indoor air quality or reduce the effectiveness of your HVAC system. The government only suggests cleaning ductwork if there is significant mold growth or obstructing material.

5. Inspect the Furnace: The first component to examine to ensure your furnace is in working order is the thermocouple, a safety device that cuts off the gas supply if the pilot light goes out. Even if the pilot light is bright, a filthy thermocouple can prevent the furnace from starting. Remove the thermocouple according to your furnace’s directions and remove any soot buildup using steel wool.

After reinstalling the thermocouple, turn on the gas valve and light the pilot light to determine whether the furnace will start up. If the furnace still won’t light, don’t worry—the thermocouple is unlikely to endure the entire lifetime of the furnace, and you may need to replace it.

Next, replace the air filter. If your furnace has a humidifier, now is the time to clean it and inspect it for mold.

6. Clean the Blower Fan: Over the summer, the furnace blower may have accumulated dust, which you don’t want to blow into the building. Remove the furnace fan cover and use a brush and shop vac to clean the blades. Examine the fan blades for broken or bent fins, and replace the blower unit if necessary. If the fan is belt-driven, check the drive belt for cracks and fraying and replace it as needed.

7. Rotate the Dampers: Poor ventilation can degrade indoor air quality and aggravate allergies. Check that your fresh air damper is admitting external air at the ASHRE standard 62.1 rate. Replace the filter, clean the intake screen, and lubricate the damper shutters. To confirm that the damper is working properly, open and close it many times. Test the operation of any smoke and fire dampers in your building. Any faulty actuators, shutters, or louvers should be replaced.

8. Clean the Compressor: Your heat pump’s exterior compressor is easy to overlook, but it needs regular maintenance. Clear plants and debris from the unit’s sides to provide proper airflow to the coils. Examine the fan for broken or bent blades, then remove any dirt from the fan. If you do not utilize a heat pump, consider protecting the compressor unit from the weather by covering it for the winter.

9. Reset the Thermostat: Run the system briefly in heat mode to ensure the controls are working properly. A faulty thermostat can shut down the entire system, so make sure to replace any facility services.

Run the system briefly in heat mode to ensure the controls are working properly. A faulty thermostat can bring the entire system to a halt, so replace any faulty switches or control panels.

10. Replace the Filters: New air filters not only clean the air in your facility, but they also minimize the strain on your blower fan. Filters should be changed on a regular basis, ideally four times each year.