Maintaining Your Heating and Cooling System


Just as your car needs tune-ups to keep it in good running order, your heating and cooling system needs regular maintenance to keep it running at peak efficiency and extend its useful life. A basic maintenance program for your heating and cooling equipment is relatively inexpensive and can pay dividends in energy savings and increased equipment life. There are some simple things you can do yourself, like changing air filters. Other maintenance tasks are better left to trained professionals. Many heating and cooling contractors offer annual service contracts that include regularly scheduled maintenance visits.

The following items should be included in a basic heating and cooling system maintenance program.

All Systems

  • Inspect all electrical connections and measure voltage and current on motors. Faulty electrical connections can cause unsafe operation and damage critical components.
  • Lubricate all moving parts. Friction can cause premature wear and increase electric usage.
  • Check system controls for proper and safe operation.

Fossil Fuel Systems

  • Clean burners, combustion chamber, and heat exchanger surfaces
  • Check fan belts and blowers in forced air systems
  • Check safety controls
  • Check thermostat operation
  • Check thermocouple and pilot light assembly (if applicable)
  • Check fuel input and flame characteristics, and adjust if necessary
  • Check for proper venting
  • Test for carbon monoxide (CO) and remedy if found
  • Check the condition of the heat exchanger - a cracked or deteriorated heat exchanger in a forced air system can allow combustion gases to mix with house air.
  • Adjust the controls on the boiler or furnace to provide optimum water and air temperature settings for both efficiency and comfort.
  • Perform a combustion efficiency test

Hot-water Systems:

  • Test pressure-relief valve
  • Test high-limit control
  • Inspect pressure tank, which should be filled with air, to verify that it's not filled with water

Steam Systems:

  • Keep radiators free of dust and objects that might obstruct the heat
  • Bleed radiators regularly once or twice a year unless the system has an automatic bleeding capability
  • Drain some water from the boiler to remove sediments
  • Test low-water cutoff safety control and high-limit safety control
  • Analyze boiler water and add chemicals as needed to control deposits and corrosion

Air Conditioners

  • Inspect, clean, or change air filters once a month - dirty or clogged filters reduce the system's efficiency and can eventually lead to equipment failure
  • Clean evaporator and condenser coils - dirty coils reduce the system's ability to cool your home and cause the system to run longer, increasing energy costs and reducing the life of the equipment.
  • Check refrigerant level and adjust if necessary - too much or too little refrigerant will make your system less efficient, increasing energy costs and reducing equipment life.
  • Clean and adjust blower components to provide proper system airflow - airflow problems can reduce your system's efficiency by up to 15 percent.
  • Check and inspect the condensate drain - a plugged drain can cause water damage in the house and affect indoor humidity levels.

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