Ask the Expert

What can I do inside my home to keep my heating or cooling systems running at peak efficiency (and maybe even save money)?

  • Replace the indoor unit’s air filter monthly.  Old/Dirty filters cause equipment to work harder, resulting in energy waste and possible internal damage.  If you have a reusable/washable filter, make sure that it has completely dried prior to reinstalling.
  • Inspect the blower compartment of your furnace or blower coil.  Use a vacuum to remove any dirt or dust, which can result in improper performance and low efficiency. Make sure that the coil is dry prior to vacuuming.
  • Remove clutter from around the furnace or blower coil.  Items stored near the furnace are fire hazards.  They may also obstruct combustion air supply.  This could cause incomplete combustion and the production of carbon monoxide gas.  Your furnace or blower coil could be located in a closet, attic, or basement.  Removing clutter applies to your equipment no matter where it is located.
  • Check the chimney or flue pipe connections for tightness, blockages or loose connections.  Your gas furnace flue pipe must remain tightly connected and free of blockage for the furnace to operate correctly. If repairs are required, contact us to schedule the repairs.
  • Set the thermostat on “HEAT” and move the temperature setting above room temperature.  Listen for any unusual sounds and call us if you suspect problems.
  • Keep return registers/grilles clear of obstructions.  The return register/grille must remain free of obstructions such as furniture, lint, dust or pet hair for the system to operate properly.
  • Clean humidifier reservoir regularly.  If your home comfort system includes a humidifier, it may be necessary to clean the water reservoir to prevent mold or mildew buildup.

What can I do outside my home to keep my heating or cooling systems running at peak efficiency (and maybe even save money)?

  • Trim brush and shrubbery near outdoor units to prevent airflow obstruction.  It is important to provide unrestricted airflow to the outdoor unit.  Leaves, trash, or shrubs crowding the air conditioner or heat pump cause the unit to work harder and use more energy.  Also remove any debris that may have collected around the unit.
  • Clean outdoor coil.  The outdoor coil on an air conditioner or heat pump can sometimes become obstructed by grass clippings, leaves, dust, etc.  If this happens, using a garden hose, gently run water over the coil removing unwanted obstructions.
  • Make sure outdoor unit remains level.  Ground shifting or settling can cause an air conditioner or heat pump to sit in an uneven position.  If this happens, re-level the unit to make sure water/moisture drains from the cabinet properly.

How often should I change a home air filter and what kind should I buy?

The filters used with a heating and cooling system make a big difference in the quality of air circulating throughout the house. Choosing the right filter ­and changing it regularly ­will help your family breathe easier.

Air Filter Basics

Home air filters, ­also commonly called “furnace filters”, keep the coils and heat exchangers on the heating and air conditioning system clean. Dirty coils and heat exchangers make the system work harder. Keeping the filter clean can prolong the life of your HVAC unit.

Of course, the filters also clean the air that you and your family breathe. The variety and amount of particles in your home’s air will depend on how many people and pets live in the house. People with allergies or asthma should be extra diligent about keeping home air filters clean.

The most important thing to remember about home air filters is to change them regularly. Even the highest-quality filter can’t do its job right if it’s clogged with a thick layer of particles. Different filters are meant to be changed at different intervals, but once a month is a common time frame. New homes and homes going through a remodel will need more frequent filter changes to compensate for the extra dust and residue in the air.

Do you have any tips for helping me remember to change my air filter regularly?

Yes. Here’s an idea: Schedule your filter changes to coincide with another regular household activity, such as paying a monthly bill, or giving pets their flea and heartworm treatments. You’ll be less likely to forget if the two activities are linked in your mind.

What are the differences between air filter types?
What Air Filter to Buy: Material and Style

You have several choices of material and style to choose from when buying a home air filter. Performance is affected by the size and density of the material used, as well as the size and volume of the particles being filtered.

The least expensive filters have a layer of fibers that can be covered by a honeycomb-shaped grill. The material is most often fiberglass (top photo on right).

Pleated filters­ (bottom photo on right) made of a variety of materials are more efficient because the pleats provide a greater surface area to trap particles. Many pleated filters are electrostatically charged to help them attract and hold microscopic particles.

Reusable filters are made of material that can be rinsed clean with water.

Some filters for window air conditioners are made of foam.

Most filters are labeled with a MERV (Minimum Efficiency Reporting Value) rating number, which measures a filter’s ability to trap particles ranging in size from 3.0 microns to 10.0 microns. MERV is an industry standard rating, so it can be used to compare filters made by different companies. (Some manufacturers also have their own rating systems.)

Residential filters commonly have MERV ratings of 1-12. The higher the MERV rating, the more efficient the filter is, and the more particles it can filter.

  • A MERV rating of 6 means the filter is 35% to 50% minimum efficient at capturing the measured particles.
  • A MERV rating of 8 means the filter is 70% to 85% minimum efficient at capturing the measured particles.
  • A MERV rating of 11 means the filter is 85% to 95% minimum efficient at capturing the measured particles.

Size and Shape

Most filters for residential HVAC systems are 1″ thick, but some large houses (3,000 sq. ft. and more) require 4″ filters because of the volume of air circulating in the home. The 1″ filters come in a variety of sizes, so be sure to note what size you need before going to the store to make a purchase.

Adjustable filters are available for non-standard ventilation openings. Special sizes and shapes of filters are available for room air conditioners, as well as for register vents and return vents in the floors, walls, and ceilings.