Why is there rust in my stove's combustion chamber?

The presence of rust inside the combustion chamber is quite normal, especially if your combustion chamber is constructed entirely from steel. It's the result of environmental exposure and normal use and is not generally considered to be a manufacturing defect.

Here's why rust can appear:

1. Condensation and humidity - wood pellet stove burn fuel that contains moisture and combustion naturally produces water vapour. If your stove isn't running hot enough or if there are periods of inactivity, moisture can condense on the metal surfaces inside the combustion chamber. This is especially the case in unheated or damp environments.
2. Ash residue - ash can attract and retain moisture which can later evaporate and cause further oxidization on metal components.
3. Air intake and storage conditions - if your stove is located in a damp room, e.g. near laundry or in a poorly ventilated area, or if the appliance was stored without adequate protection from moisture, oxidization may occur more rapidly.

Why rust isn't covered under stove warranties:

Surface rust is generally classified as "wear and tear" due to environmental factors or insufficient maintenance, which falls outside manufacturer's warranty inclusions. Rust can only occur if moisture is present and moisture can only be present if introduced by external factors, e.g. wood pellets, high humidity levels in the home (or outside).

How to manage rust in your appliance:

• Run the stove at higher power levels occasionally if rust is persistent during operation.
• Perform regular cleaning of the firepot and ash pan to prevent moisture build-up in ashes.
• Get your stove professionally serviced at the end of the heating season.
• Use high-quality wood pellets with a low moisture content (this can be checked on your pellet's technical information which should be printed on your bags).
• Ensure your home is well ventilated and that your relative humidity levels are not too high.
• Consider the application of an anti-corrosion spray during off-season when the stove is not being used.