Summarized from: SEER Facts Bulletin, www.advancedenergy.org

Many people know that SEER ratings are important in selecting HVAC equipment, but most people don't realize that the HVAC contractor has a major role in making equipment perform up to its real capabilities.

SEER stands for Seasonal Energy Efficiency Ratio. It's a number that describes how well air-conditioning and heating equipment works. A higher SEER means better efficiency and lower energy bills.

Real conditions, not controlled lab conditions, determine how equipment will perform. That's why understanding how SEER is affected by actual field conditions will help you get the most benefit from higher SEER equipment.

Manufacturers of the condensers and evaporators used in HVAC equipment usually specify the system conditions that should be met in order for their equipment to achievethe best performance results. But field experience often shows that these conditions are not being realized, and the equipment performs lower that its rated SEER.

Airflow, charge, tight ducts, and sizing-each one plays a key role in how air-conditioning equipment actually performs in the field. Ignoring any one of those factors can result in a significant loss in equipment performance. But the combined effect of problems from multiple factors can add up to a huge decrease in performance. It is not uncommon to find air-conditioning systems in the field that deliver only half of the potential benefit from its high SEER rating.

The HVAC contractor plays a major role in ensuring that business owners get the benefits of the SEER level that manufacturers build into the equipment. They can effectively enhance comfort, reduce initial equipment costs, make equipment last longer, and reduce monthly energy bills by managing the following field adjustment performance factors:

• Airflow for the system near 400 cfm per ton
• Charge refrigerant properly
• Tight ducts avoid leak to outside
• Size equipment correctly