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Rentmeister Total Home Service Blog

Why do Furnaces Need an Exhaust Flue?

While it may not be the most glamorous part of your furnace, the exhaust flue is the most important part for ensuring your safety. Furnaces produce a number of harmful and potentially deadly gases, and without a properly functioning flue those gases become trapped in your home. A well-maintained flu directs all of these harmful combustion byproducts out of your house, allowing you to turn up the heat without worry.

Combustion Byproducts

As the furnace burns fuel a number of gases are produced, collectively known as “combustion byproducts.” These include carbon monoxide, nitrogen dioxide, and sulfur dioxide. Heavy or prolonged exposure to these gases can have devastating effects, and thousands die every year as a result of being poisoned by them. Even low level exposure can be dangerous if it occurs over a long period of time. Symptoms of low level exposure include nausea, fatigue, unconsciousness, headaches, and disorientation. The best way to prevent exposure to these byproducts is by properly maintaining all carbon fuel-burning appliances, including furnaces.

Maintaining Your Flue

The two things required for the flue to do its job correctly are a clear path of egress and proper furnace ventilation. If the flue vents through a chimney, make sure that the chimney is clear of debris that might block the flue access. This will allow the combustion byproducts to vent out of the home. Proper furnace ventilation is a bit more difficult. If the furnace is not getting enough oxygen to maintain heating, it will draw in outdoor air through the flue. This causes the flue to operate in reverse, potentially trapping combustion gases in your home. The easiest way to fix this is to install ventilation ducts to direct more air to the furnace.

Even if you don’t notice any problems with your furnace, it is recommended that you have it checked by a professional once a year. If you haven’t had your furnace serviced yet this year, call Rentmeister Total Home Service. We are experts in heating repair service covering the entire Salt Lake City area.

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