Improvements in furnaces have increased dramatically over the past thirty years. Manufacturers have made great strides in the areas of:
Older furnaces installed in Howard County from the 1970's and 1980's had an AFUE of about 60%. This figure indicates how efficiently your furnace uses the fuel that it consumes—the higher the number, the better. Today's Federally mandated minimum is 78.5% and some furnaces have efficiency ratings as high as 96% AFUE.
Today's furnaces are built to operate more safely. There are numerous safety devices that prevent the equipment from coming on unless all components are functioning normally. There must be adequate air flow across the heat exchanger, the pilot must be lit, and all service access panels must be securely in place before power and gas will be supplied to the unit.
One innovative new feature available on furnaces is two-stage heat, which enables the furnace to change its output depending on demand from the thermostat. No longer are systems limited to one output level.
When heat is replaced in the house as evenly as it is lost—(the temperature remains constant without big temperature swings) you are provided with optimum comfort. Additionally, when the furnace operates on "low", the fan motor will also run at a slower speed, ensuring warm delivery temperatures and quieter operation.
Another innovation is the variable speed motor. These motors perform under a wide variety of output requirements, depending on what the furnace is being tasked to do— high-fire, low-fire, cooling or to simply circulate air through the living space. They also use about 25% less electricity than traditional PSC fan motors.
Whenever you are considering the replacement of a piece of equipment, it is important to call us ahead of time for an assessment of your installation requirements.
Furnaces have combustion air requirements that were largely ignored twenty years ago but that are now critical to the safe operation of today's equipment. Local codes also have very specific requirements for the venting of gas furnaces.
The ENERGY STAR label identifies products that meet EPA standards for energy efficiency. The minimum efficiency rating for furnaces is 90 AFUE.