Main Heating and Cooling's Furnaces

Lennox Furnaces by Main Heating and Cooling

One of the more difficult decisions you'll have to make about your Furnace is when it's time for a new heating system for your home. You have been researching online or have heard people 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 terminology.


Furnace Efficiency Rating AFUE

All of today's modern Furnaces and Boilers efficiency is measured by annual fuel utilization efficiency (AFUE). To be 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 98 AFUE means for every dollar you spend to heat your home 98 cents is returned in heat and 2 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.


A 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 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 will save you on your monthly energy bills.


Variable Speed Furnace

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 and cold spots in your home. If using a AC unit with the furnace the variable speed greatly improves humidity control which saves you more money on home cooling costs during the summer.


Variable Capacity Furnace also called Modulating Gas Furnaces

This type 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 98.5% efficiency.



Lennox Signature Collection SLP98v

  • Efficiency rating of as high as 98.7% AFUE
  • Energy Star rated
  • SilentComfort Technology and Sound Absorbing Insulation
  • Air Filter and Humidifier Compatible
  • Blower motor: Variable speed
  • Gas Valve: Variable-Capacity Gas Valve- Adjusts capacity output in as small as 1% incerments for the ultimate in precision comfort
  • SureLight Silicon Nitride Ignitor
  • Ultra-Low Continuous Fan
  • Vairable-Speed air flow which helps control humidity
  • Parts Warranty 10-Year Limited Warranty on covered components.
  • Heat Exchanger Warranty Limited Lifetime Warranty
  • View Brochure



Lennox EL296V High-Efficiency, Two-Stage Gas Furnace

  • Efficiency rating of 96% AFUE
  • Energy Star rated
  • SilentComfort Technology and Sound Absorbing Insulation
  • Air Filter and Humidifier Compatible
  • Blower motor: Variable speed
  • Gas Valve: Two Stage operation for efficiency and comfort
  • SureLight Hot Surface Ignition
  • Ultra-Low Continuous Fan
  • Parts Warranty 5-Year Limited Warranty on covered components. This product may be eligible for valuable 10-Year Limited Extended Warranty coverage with product registration.
  • Heat Exchanger Warranty Limited Lifetime Warranty
  • View Brochure



Lennox Merit Series Ml180 Standard-Efficiency Furnace

  • Efficiency rating of 80% AFUE
  • Energy Star rated
  • Steel Cabinet for quit operation
  • Air Filter and Humidifier Compatible
  • Gas Valve: Two Stage operation for efficiency and comfort
  • SureLight Hot Surface Ignition
  • Parts Warranty 5-Year Limited Warranty on covered components. This product may be eligible for valuable 10-Year Limited Extended Warranty coverage with product registration.
  • Heat Exchanger Warranty 20 year Limited Warranty
  • View Brochure


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