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What to Look for in an Energy Efficient Furnace

January 10, 2014

When you consider that nearly 44% of a homeowner’s energy bill goes towards heating and cooling costs, it’s no surprise that more people are opting for energy efficient furnaces. But how do you know which is the right furnace for you?

  1. Size Does Matter!
    Many home furnaces are actually far too large for the spaces they need to heat. A high efficiency furnace should be sized 30-40% larger than the calculated heating home heating requirements.
  2. What Counts as Energy Efficient?
    Look for a furnace with at least 95% annual fuel utilization efficiency (AFUE). The AFUE is the percentage of fuel turned into heat – the higher the percentage, the more energy efficient the furnace. Choose a furnace with an ENERGY STAR label; ENERGY STAR requires a minimum 95% AFUE.

  3. Two-stage or Multi-stage Burners Are Best
    Energy efficient furnaces are equipped with either two-stage or multi-stage burners that burn fuel at different rates. What this means is that in most weather, the furnace will utilize the more efficient low-fire settings to warm the home, and automatically switch to a high-fire setting in very cold weather when additional heating capacity is needed. Two-stage and multi-stage furnaces are 5% to 8% more energy efficient than single-stage burner furnaces, which run at full power all the time.
  4. Get a DC or ECM Fan Motor
    Many times the fan motor is overlooked when purchasing a furnace, but it shouldn’t be. An inefficient fan motor will use a lot of electricity, leading to inflated energy costs. For example, using an inefficient AC motor to power your furnace fan is like running an 800-watt light bulb while the furnace is on. By contrast, using a more efficient DC (direct current) or ECM (electronically commutated motor, which is a brushless DC motor) motor is equivalent to running a 200-watt light bulb instead. That’s a significant difference in the amount of energy used!

  5. What Role Does the Thermostat Play?
    To maximize efficiencies, get a programmable thermostat that can perform a temperature setback overnight or when the house is unoccupied. There’s no point in heating an empty home!

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