If you have a coal-burning furnace, you know how effective and affordable it can be to heat your house. Rusting is a problem that many owners of coal furnaces deal with, though. If left uncontrolled, rust may seriously harm your furnace and make it look ugly. We’ll go over some advice on how to stop your coal-burning furnaces from rusting in this post so you can maintain them in good working order for years to come.

Use Lubricants

Thoroughly clean the furnace or stove. Scrap all the scale and debris from the firebox walls and grates. If you have a stoker, you must empty the hopper and coal pot completely. Once the coal stove or furnace is clean. Use WD40 and spray down the entire inside of the unit, even the hopper. If you have a stoker, now would be an excellent time to use all-purpose light machine oil to oil bearings and motors.

Use an Incandescent Light Bulb

If your coal stove or furnace is in a wet or humid environment, place a 100w incandescent bulb in the firebox after cleaning. This bulb will create enough heat to keep moisture from clinging to the unit’s walls.

Water Leaks And High Humidity

One of the most common causes of furnace rust is water leaks near your furnace, either from pipes or outside rain and weather. The moisture can also enter your heating system through the return ducts if your home is humid. To prevent this issue, invest in waterproofing solutions, such as improved drainage and downspouts, caulking, and weatherstripping. Also, fix any plumbing leaks.

To keep humidity levels under control, consider using a de-humidifier. These devices maintain ideal humidity levels to improve indoor air quality and prevent moisture-related problems such as mold and rust. 

Leaking Air Conditioning

Your furnace and air conditioner are often located together, and a leaking AC can affect your furnace. If the condensate drain line is clogged or the drain pan is cracked, water can leak into your furnace and cause rusting. To avoid this problem, schedule regular AC maintenance and check the drain pan for damage or overflowing. Clean the condensate drain line with vinegar every three months to prevent blockages.

The best way to avoid furnace rust is to set up a regular coal furnace maintenance schedule with a qualified HVAC technician. Additionally, ensure that you have working CO detectors on every level of the home and outside each sleeping area. These detectors will alert you to any potential gas leaks or combustion problems.

Furnace rust is a common issue that can significantly affect your heating system’s performance and lifespan. By following these solutions, you can prevent furnace rust and maintain the efficiency of your coal burning furnace.