Should I Replace My 15 Year Old Air Conditioner?

Replacing your system with a new high-efficiency model is probably the best investment you can make in energy efficiency. You could save hundreds of dollars in air conditioning costs over the next five to seven years. Replacing an old unit with a new, efficient model should pay for itself within that time period at current electricity prices (see How Much Will It Cost?). Also, because replacement costs $700-$1,000 less than other possible measures, other improvements or repairs may become unnecessary.

Here are some factors to consider when deciding whether to replace your air conditioner:

1) Is it too small for your needs?

2) Does it have-E windows?

3) Is it too old?

4) Is it inefficient?

If your air conditioner is undersized, the compressor will have to work harder than necessary. If you have storm windows or if your house has high-efficiency windows, you’ll need a larger unit to maintain the same comfort level. This means that the old system’s capacity may be up to 20% too low for your home when new double- paned windows are installed. The higher the E window rating of the existing system, the bigger its replacement should be in order to provide comparable cooling performance. If your air conditioner is more than 10 years old and isn’t equipped with an efficiency rating of 13 SEER or more (or 12 EER or more on gas units), replacing your air conditioner is the best way to significantly reduce your cooling costs.

If you have a central air conditioner powered by a gas burner, avoid units with less than 80% AFUE rating (efficiency) because they waste fuel and money. Very old units with an efficiency of 65% or less can be twice as expensive per BTU of cooling as a new model costing about the same amount. Replacing a unit with constant fan operation that’s more than 10 years old may also save significant energy costs in most homes without needing any other repairs.

In addition to higher efficiency, replacement air conditioners provide these additional benefits: * Improved indoor air quality * Increased comfort-reduced noise levels and fewer drafts * Legal compliance-meets standards for lead content * Warranties-new systems carry a 1-year labor and parts warranty and a 10-year sealed system warranty

Old, dirty air conditioners lose efficiency. EPA studies indicate that the average central air conditioner performance is reduced by 25% because of decreased airflow resulting from clogged filters and strainers. If your old unit has 4 or more tons of cooling capacity, it should be checked for proper airflow at least every 2 years. Dirty coils also create poor indoor temperature control.