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Does Rust on My Furnace Just Mean It’s Getting Old?

Rust and age go hand-in-hand, but when it comes to your furnace, rust is an indicator that it’s time to call for help. Your furnace should not develop rust, even if it has some age to it. Why not? Your furnace doesn’t work with water in any capacity, like a boiler does. As such, rust indicates there is a moisture problem somewhere around your furnace, and this problem should be resolved as soon as possible. Once rust and corrosion take hold, it is just about impossible to stop it.

Why Is the Rust There?

There are a few ways your furnace can be exposed to the elements that lead to rust development:

  • Improper expulsion of vapor – the combustion process is hot, but as the hot gases and vapors move away from the heat of the burner and make their way toward your flue through the heat exchanger, they cool and can turn into water vapor. If there isn’t proper ventilation for the gases and water vapor, the water vapor can corrode the metal of the heat exchanger and flue.
  • Dripping AC – if you have a combination furnace and air conditioner HVAC, the air conditioner evaporator sits on top of your furnace. Sometimes the condensation that develops in the evaporator coils drips through the coils and instead of draining properly, lands on top of your furnace unit. The combination of water and air leads to the development of rust.
  • You have faulty ductwork – Faulty ductwork can be ductwork that has holes and cracks or ductwork that has not been properly installed. In either case, water can run down the ductwork to your furnace, where the water helps create rust.

The bottom line is that rust on your furnace in Eugene, OR, means it is time to call your Comfort Flow Heating technician for repair help.

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