Air conditioning season is now upon us and many of you will find yourself in the position of needing a new air conditioning system for your home this year. There are many things to consider when it comes to purchasing a new AC system, after all it is quite the expensive investment. You have to pick the right contractor, make sure you have financing in place if needed, and do a little homework about air conditioning in general. An educated consumer is the best kind in my opinion.
The acronyms you are going to hear a lot when comparing AC systems is SEER or EER. SEER stands for Seasonal Energy Efficiency Rating and EER stands for Energy Efficiency Rating. The difference between the two is SEER is used by the manufacturers and EER is used by government and other official agencies. Today we will wander down the SEER/ EER path and separate facts from fiction.
I am going to focus mostly on SEER rating for the purpose of this post. The SEER scale, depending on the region and the tonnage or BTU’s of cooling the unit has is between 13 and 25, obviously the higher the number the more efficient the unit is. In our region, 14 is the minimum SEER rating we are allowed to install per Florida building code. Only in northern regions will you find equipment rated at 13 SEER.
Each SEER point you go up will typically save you around $100 per year in electrical consumption. In theory a 21 SEER unit is $700 per year less expensive to operate than the basic 14 SEER. The reason I say “in theory” is that SEER rating from the manufacturer is impacted by many other factors. When the efficiency of the unit is tested it is done in laboratory conditions with no duct work, no filters, and is perfectly clean. Obviously, those are not real-world conditions. In real life we have duct systems, filters, dust and dirt building up in the unit and all these things lower SEER rating.
Bottom line… you will save money on your utility bills with higher SEER rated equipment, however unless one of you has very good psychic abilities the exact savings is impossible to calculate. Some of the reasons why are:
- Leaky ducts: A recent study showed at 30% duct leakage an 18 SEER unit will be operating around a 10 rating.
- Proper install techniques: Not following manufacturer recommendations during the install process can reduce efficiency.
- Correct refrigerant charge: If refrigerant levels aren’t correct in the unit say goodbye to any efficiencies.
- Unit is dirty: Improper filter maintenance or just lack of maintenance on the system in general reduces efficiency.
- Air handler location: Air handlers that are inside the conditioned space operate better than units in the garage or attic.
These are just a few of the things that can lower the efficiency of your new unit and you may not get the electrical savings the sales guy promised you, so as always — buyer beware. Do your homework, get educated and please remember the purchase of your new air conditioning system will impact the next 15 years or so of your life or for however long you stay in the home.
I’m off to see a man who is thinking about buying a house and would like my opinion on the overall condition of the air distribution system… smart man! Until we meet again, did you ever wonder what would happen if you played a country song backwards? Dog and wife come home? You quit drinking? Pick-up truck not stuck in the mud anymore…
House Whisperer out!!