Why Is There Rust on My Furnace?The variable weather in Niles, OH, means that you’ll frequently turn to your furnace for relief in the late autumn, throughout the wintertime, and into the spring season. If you notice rust on your furnace, you might wonder what caused it to appear and whether or not it’s a problem. Knowing the reasons why furnaces get rusty will help you to take action and know when to call for a furnace inspection or repair.

Combustion Process

The combustion process creates byproducts that interact with metals. Some of those byproducts are oxidizing gases. They interact with the oxygen in the metal, leaving rust behind. When metal gets rusty, pieces of it flake off. If too much rust develops on the furnace’s heat exchanger or combustion chamber, this is a serious issue. The deteriorated metal may fail, and this would allow the toxic combustion gases to enter your home. If you notice rust on the combustion chamber or heat exchanger, you’ll need a prompt furnace inspection. The gas supply, air supply, burners, or other components may need to be repaired, adjusted, or replaced in order to curb the development of rust.

Poor Venting

The byproducts of combustion must be ventilated to the outdoors. A problem with your furnace’s ventilation system may hasten the development of rust. For example, a damaged fan won’t be able to ventilate the hot, acidic combustion gases out of your house fast enough. This allows the gases to interact with the metal in the ductwork and your furnace. The ventilation system should be inspected and cleaned every year during your annual heating system tune-up.

Blocked Flue

If a blockage in the flue or the flue’s opening to the outdoors occurs, then the water vapor and combustion gases will be unable to escape. This gives the steam and acidic gases more time to cause rust in your furnace.

Improper Humidifier Settings

Many newer furnaces have a built-in humidifier. If the humidifier is putting too much moisture into the air, some of that moisture will also get into your furnace. Set the humidifier to maintain a consistent humidity level of about 40% in your residence. In the summertime, you may need to run a dehumidifier in order to remove the excess moisture left behind by your air conditioner.

Moisture in Ducts

Moisture in DuctsMoisture in your home’s ductwork can get into your furnace and cause interior rust. Outdoor moisture can also get into the heater through duct openings. The ducts in your kitchen, bathroom, and laundry room are the most likely to have moisture droplets. When cooking, bathing, or cleaning, always use exhaust fans. These fans minimize the amount of moisture that gets into the ducts. Run the fan for an additional 10 minutes after you finish any steam-generating activity.

Location in Your Home

If your furnace is located next to your water heater or the indoor portion of your air conditioner, moisture from those units may lead to rust on your furnace. Furnaces located near sump pumps or washing machines can also rust faster than those that aren’t placed close to these sources of moisture. If your furnace is in the basement, it may rust faster than it would if it was above ground. If your house is located on property with a high water table or your basement has ever flooded, exposure to the condensation and moisture will cause rust.

Air Conditioner Obstruction

If your residence has central air conditioning, it will use the same blower as your furnace. Any leftover moisture in the air conditioner could trickle into the air handler and make its way into your furnace. A clog in the air conditioner’s condensate drain pipe could also cause a moisture backup into the air handler and your heater. If you ever notice water leaking from the air conditioner, it’s a good idea to have your furnace inspected for leaks, too.

Clogged Gutters or Downspouts

You might be surprised that a roof or gutter issue could affect your furnace. Water that pools in the gutters or downspouts persists near your home’s foundation. This moisture gets into your house, where it can cause rust on your furnace.

A To Z Dependable Services is a trusted furnace maintenance provider in Niles. We’re also available for air conditioner maintenance and heating and cooling repair, installation, and replacement services. Our plumbing services include installations, maintenance, and repairs. We also install bathtubs and showers. For more information about why furnaces get rusty, contact us at A To Z Dependable Services today.

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