Guide to Energy Efficiency 7 - Properly Sized Equipment Guide to Energy Efficiency 7 - Properly Sized Equipment

When purchasing heating and cooling equipment, choosing energy-efficient products is a step in the right direction. However, asking the right questions of your contractor and making sure your equipment is properly sized and installed are also important elements to ensure that your new system performs at optimal efficiency.

When it comes to heating and cooling equipment, bigger doesn't always mean better. Larger capacity systems are intended to meet the needs of a larger heating or cooling load. However, if the unit is too large for your home, you will experience less comfort and increased costs. Oversized equipment will operate in short run times or cycles, not allowing the unit to reach efficient operation. In addition, oversized equipment will not run long enough to remove humidity from the air. This can leave you feeling cool but not comfortable.

Don't assume that the size of your new system will be the same as your old equipment. Changes, such as additions or insulation improvements, may have been made to the house since the original equipment was installed; or, the equipment may have been too large from the start. Expect the contractor to gather information about your house such as the level of insulation, type and size of the windows, and floor area. Your contractor can determine the right size for your heating and cooling equipment by using ACCA/ANSI Manual J®, or an equivalent sizing calculation tool that takes these and other factors into consideration.

When installing your new heating and cooling equipment, your contractor should do the following to ensure a quality installation:

Quality Heating Installation Checklist:

  • Provide adequate room around the equipment for services and maintenance.
  • Test and verify proper airflow (if furnace or heat pump).
  • Verify that your furnace or boiler has been tested for proper buner operation and proper venting of flue gases. The vent piping should be inspected for leaks or deterioration and repaired or replaced as necessary.

Quality Cooling Installation Checklist:
  • Provide adequate room around the equipment for service and maintenance.
  • Replace the indoor coil of the equipment when replacing the outdoor unit. To get the expected level of efficiency, you should have a matched set. An old coil will not work efficiently with a new outdoor unit.
  • Confirm that the level of refrigerant charge and the airflow across the indoor coil meets the manufacturer's recommendation. It's estimated that more than 60% of central air conditioners are incorrectly charged during installation.
  • Place the condenser in an area that can be protected from rain, snow, or vegetation, as specified by the manufacturer. If you have a central air conditioning unit, cover your outside equipment during the winter to protect it from snow and ice. Heat pumps need to be left uncovered to properly operate during the winter.

Approved for publishing by the EPA

Got a New Project You're Proud of?

Post it on Your Projects!