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Drive-thru hours

All of our services are now available online. If a drive-thru visit is required, our new drive-thru hours are Mon-Fri, 8-12 and 1-5.

A Look Inside your Natural Gas Furnace

As our infographic shows, it is cold outside and your gas forced-air furnace has kicked on to warm up your home.

  So how does the furnace produce heat?  Let’s take a look inside to find out.

  1. The thermostat tells the furnace the room temperature has dropped below a preset comfort level by sending a low-voltage electrical signal to a relay in the furnace.
  2. The induced-draft fan motor turns on.  A gas valve then opens and delivers natural gas to the burners.
  3. The pilot light or electric ignition lights the burner inside the combustion chamber.  Thermocouples first detect whether the pilot light is on or not and then whether flames are present.
  4. The combustion exhaust from the burner flames travel through the inside of the furnace’s heat exchanger.  Once the heat exchanger reaches the appropriate temperature, the blower kicks on and sucks air into the furnace.  The air is heated as it moves across the hot heat exchanger surface.
  5. The blower pushes the warm air into the hot-air supply plenum and then forces it out to the rooms through ductwork and supply vents.  Cold-air return ducts bring room air back to the furnace for reheating. 
  6. The combustion gases are vented through a flue in the roof or through a wall.

Do you know who invented the modern furnace?

Alice H. Parker.  In 1919 Parker received a patent for a new heating system.  The design is considered the first hearing system with independently controlled units and fueled by natural gas.

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