The common home heating solution

Furnaces can be powered by fuels like oil, natural gas or propane, or with electricity. The most common types found in residential homes are electric and natural gas furnaces.

Natural gas furnaces generate heat by burning fuel. The hot gas resulting from this combustion passes into heat exchangers (curved metal tubes), which transfer the heat to air flowing through the home's air ducts and into the home. Gas furnaces create carbon monoxide, a colorless and odorless gas, that's released outside through a vent or pipe. Carbon monoxide poisoning occurs when a crack or leak forms in your gas furnace, allowing CO into your home. This is why installing carbon monoxide detectors within the home and having your furnace serviced annually are so important.

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Electric furnaces are both cleaner and safer than gas furnaces. However, they are also twice as expensive to run. Electric furnaces use electricity to create heat with wire coils. Air is forced into a heat exchanger via an air fan and enters the home through a duct system.

Furnace Filters

Your furnace filter is key to the efficient operation of your furnace and the air quality in your home. Although some furnace filters are very inexpensive, many of them will only catch about 75 percent of bulk dirt and 3 percent of minute pollutants.

Treated furnace filters are generally more effective. These disposable furnace filters are treated with dirt-trapping glycol or mineral oil. They may only capture about the same amount of bulk dirt, but they can catch about 10 percent of the smaller, microscopic particles. Most disposable filters are made of fiberglass or carbon and cost less than $10 online. You should replace your furnace filter every month, or as needed, to cut down on heating bills.

Electronic furnace filters or electrostatic air filters are the most effective. Some brands claim to remove up to 97 percent of large particles and 70 percent of microscopic particles. Most permanent furnace filters range in price from about $60 to $400 online for a complete unit. These can often last for years, but need regular cleaning to stay effective.


Your home's heating and cooling systems are controlled by a small piece of equipment called a thermostat. Today, most homes have a digital thermostat with a programming option.


Digital thermostats are preferred over mechanical thermostats because they can be programmed to raise or lower the temperature automatically at set times of the day. This way, for example, you can avoid heating the house when no one is home during the day. Digital thermostats measure temperature by means of a thermistor. This is an electrical resistor whose resistance change depending on temperature. A microcontroller measures the resistance in the thermistor and converts it to a temperature reading. The thermostat turns the furnace on or off based on this reading, to maintain the temperature you have programmed.

Your thermostat should be located in a room that is used frequently. In order to read your thermostat easily, it should be installed at eye level. It should also never be placed on an outside wall, near a window or be exposed to direct sunlight or other heat-conducting appliances.

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my rheem furnace is making a loud clanking sound when turning off. It sound likes something is hitting the fan or a fan inside is rusted and makes this sound at the end of the cycle.
Posted on 3/29/2012 12:21:00 PM by Anonymous
My Rheem furnace turn on for about a minute, not the fan, but before the fan blows out the air it turns off. The fan works by itself. I am thinking the furnace turns on because I hear the noise.
Posted on 3/18/2012 7:22:00 PM by Anonymous
My trane x80 furnace is igniting, running and shuts down, and repeats. The filter is clean. The thermostat is set at 72 but temp is only 63. What is the problem.
Posted on 1/1/2012 7:43:00 PM by Anonymous
what would cause my hot water not to heat up when my furnace isnt on
Posted on 11/18/2011 11:07:00 PM by Anonymous
My trane furnace, pilotless and about 60000 Btu and it ignites, runs for about 1 or 2 minutes and shuts down. Then it begins the same cycle all over again repeating this every 2 minutes. The thermostat is set at 74 but the temp is only 62. What is the problem?
Posted on 11/10/2011 10:17:00 AM by Anonymous
I need to know what I have to do to close down the Taylor wood burner system. My husband is not able to do the things necessary to use this winter. I cannot find my info on it, Thank you./Helendamaris@embarqmail.com
Posted on 9/28/2010 12:49:00 PM by Anonymous
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