Frequently Asked Furnace Questions

C & C Heating & Air Conditioning handles Lennox furnaces. If you trust us to heat your home, we will do our part by only offering equipment from the premier name in heating.

As a homeowner, one of the hardest decisions you’ll have to make about your Furnace is when it’s time for a new heating system. You’re researching online or have heard talk about variable speed heating, single stage, two stage and modulating gas valves and AFUE ratings. Let us help you by explaining some of those furnace systems and related terms.

  • Furnace Efficiency Rating AFUE

    All of today’s modern Furnaces and Boilers efficiency is measured by annual fuel utilization efficiency (AFUE). To be more specific, AFUE is the ratio of annual heat output of the furnace or boiler compared to the total fossil fuel energy consumed by a furnace or boiler in a year.
    For example, a furnace rated at 80 AFUE means for every dollar you spend to heat your home 80 cents is returned in heat and 20 cents is lost. The AFUE rating does not include how much heat energy is lost through the ductwork of the heating system. Leaking ducts or non-insulated ductwork running through a cold attic will increase how much is lost.

    An 80 AFUE rated furnace compared to older furnaces which recover only 45-65 cents worth of heat, these 80 AFUE furnaces are affordable and good choices for your home. To get the maximum worth out of each dollar spent on gas, a 98% plus operating furnace is the best option available. Each dollar spent in turn brings over 98 cents back in heat to your home.

  • Single Stage Furnace

    This is the least expensive furnace. Also, this type of furnace is the least technical, which means it is easy to install and repair making them the most common furnaces. Single-stage means the furnace will use the same size of flame to produce heat regardless of the temperature outside or inside. So with single-stage furnaces, the furnace is cheaper to buy but your monthly utility bills with be higher to operate this type of furnace.
  • Two Stage Furnaces

    The furnace has two stages of heat, a smaller size flame for those chilly days and a larger size flame for those really cold days. This allows the furnace to stay on longer while burning less gas. This helps to keep your home more comfortable. And because the furnace actually slows down, noise is also reduced. A two-stage furnace costs more initially but will save you on your monthly energy bills.
  • Variable Speed Furnace

    Variable speed furnace does not actually refer to the furnace itself; it refers to the furnace’s blower motor. The term “variable speed” refers to the furnace’s indoor blower motor, which moves air at different speeds to precisely control the flow of heated and cooled air throughout your home. These variable-speed motors use way less energy than the standard blower motors and increase the furnaces AFUE rating. These variable speeds also provide a quiet, consistent flow of air for enhanced comfort to help eliminate hot/cold spots in your home. If using an A/C unit with the furnace the variable speed greatly improves humidity control which saves you more money on cooling costs during the summer.
  • Variable Capacity Furnace also called Modulating Gas Furnaces

    This type of furnace goes beyond the two-stage furnace by varying output between 35% and 100% only using the amount of fuel needed to maintain the desired temperature. The variable capacity furnaces are among the most energy-efficient furnaces and are rated above 98% efficiency.
    Lennox furnaces are some of the most efficient and quietest heating systems you can buy. They’re engineered for perfect warmth, energy savings, and dependability.