Air conditioning maintenance tips

Published 5:54 pm Wednesday, August 2, 2023

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Running the air conditioning can be costly, but regular maintenance helps a system to work more efficiently. It also enables homeowners to recognize issues that can lead to expensive repairs if left unchecked.

  • Change the filters. Dirty, clogged filters can cause a system to work harder to cool down rooms, compromising efficiency. Check the HVAC system’s manufacturer recommendation for how frequently to change the filters. Some may benefit from monthly replacement if the air is running constantly.
  • Consider the MERV rating. The filter will have a minimum efficiency reporting value, or MERV, according to This Old House. The higher the number, the better the filtration. But a higher MERV rating requires more energy to pull air through the filter. Therefore, choose a balance of filtration and energy cost requirements.
  • Maintain the outdoor unit. Clean the AC unit with a soft-bristle brush and vacuum the fins at the start of the season and if the unit becomes dirty from weather, pollen and other elements. Bent condenser or evaporator fins can restrict air flow that would normally pass through the air conditioning system. Gently straighten them to improve air flow.
  • Check and repair leaks. Airflow leaks through ductwork and with window AC units can reduce efficiency. Hold an incense stick or another smoldering item to check for leaks. If the smoke blows around, there is leakage. Use foil tape to seal small gaps and duct mastic for large ones. Stuff foam around a window unit and use taping as necessary.
  • Supplement with a whole-house fan. The Family Handyman says an attic-mounted fan pushes hot air out through the attic vents and draws cooler, outside air through open windows and doors. The whole-house fan can be used to draw out most of the hot air before turning on the AC, or as a substitute on cooler days when having the AC on may not be crucial.
  • Schedule annual maintenance. Homeowners may be able to handle various maintenance tasks, or they may want to have an HVAC technician come out and do the following: clean and inspect coils; adjust and replace fan belts; lubricate motors and bearings; inspect controls and safeties, check refrigerant; and determine if the unit is large enough for the home.

Air conditioning systems need routine maintenance to operate efficiently and at the lowest cost possible.