What is SEER?SEER stands for Seasonal Energy Efficiency Ratio, and is a needlessly complex way of measuring the efficiency of your air conditioner or heat pump.
Unlike AFUE, which directly measures the amount of fuel that your furnace transfers into heat, SEER is an arbitrary scale of around 7 SEER (old, obsolete air conditioners), to 14 SEER (new, base-model air conditioners), to around 21 or 25 SEER (state-of-the-art, high-efficiency air conditioners).
At ASM, we typically don't recommend that our customers buy more than a 14 or 16 SEER unit, as the added financial cost for a high-SEER unit is unlikely to be offset during the lifetime of the unit.
For more on SEER, try:
What's a Good SEER Value for My House?