What is SEER, 2-stage furnace, Variable indoor units?
The SEER rating on A/C units is basically the units efficiency. The abbreviation, SEER stands for "Seasonal Energy Efficiency Rating." The standard rating on all A/C units is 10.0 SEER, for each additional point, or SEER, your efficiency is raised approximately 10% - much like gas mileage in your car. the 12.0 SEER units are 15 to 20% more efficient than a 10.0 SEER and the 14.0 SEER units are 15 - 20% more efficient than the 12.0 SEER unit. Therefore, a homeowner who decided to upgrade their equipment to a higher efficiency unit, can save substantially on utility costs through out the cooling season.
Standard furnaces are a single, 80% efficiency, natural gas furnace. A 2-stage furnace simply heats the home in 2 stages instead of a single stage, which makes this furnace more efficient. The 2-stage 100,000 BTU furnace, for example, starts at a slower fan speed than a single stage and only brings on 3/4 or 70,000 BTU's of heat. This process results in a quieter operation as well as the reuse of heat from the ceiling level down into the livable space due to longer run time. In addition, this results in a more consistant air temperature through out the home all at a savings of 10-15%. What happens when our weather gets really cold? The 2-stage furnace will automatically go to the 2nd stage 100,000 BTU heat after 10 minutes of run.
Variable Indoor Units
The variable option of the indoor unit can be helpful in many ways.
1. The indoor fan can be left on the "on" position to circulate air for a more even temperature through out the home costing only pennies a day. Summer or Winter, uses same energy as a 75 watt light bulb.
2. When installed with a high-efficiency filter, the variable fan option can improve air quality in your home.
3. Variable speed indoor units dehumidify indoor air in the Summer creating a more comfortable environment at a higher temperature.
4. Variable indoor units do not dehumidify air as badly in the Winter as a single speed unit creating more comfort in the Winter.
5. Variable units improve A/C units efficiency in the summer.
6. Variable speed indoor units are not much quieter in operation than single spped units due to the variable speed operation. Reason being, due to variable speed blower ramps, the speed up and then back down when the A/C or heat units come on.