How Does a Pellet Stove Work?

A wood pellet stove is a specific type of stove designed to use wood pellets as a fuel to heat and warm your home.

Pellet stoves have revolutionized the way people heat their homes and remain one of the cheapest and most environmentally friendly forms of heating.

Wood pellet stoves appear very similar to other types of stoves such as wood burning stoves and just like them utilize wood as fuel, however, that is where their resemblance ends.

The major difference is that pellet stoves have been designed to be electronic, enabling them to be equipped with a selection of innovative features such as a motor, fans and automatic ignition.

These innovations have created a stove that is much easier to use, safer and convenient than other forms of heating. So, what are the major components and how does a pellet stove work?

Here is an overview of the main components of a pellet stove and how it functions: 

1. The Hopper 

To begin, the pellet stoves are fed into the hopper, which is typically located on the top or bottom of the stove. The hopper is where the pellets are stored immediately after being deposited into the pellet stove itself.

The typical pellet stove model has a hopper with a holding capacity of around 50 to 150 pounds of pellets, and of course, the larger the hopper the longer the pellet stove will burn.

The speed at which the stove operates with each fueling is determined by both the hopper size and the rate of burn, with the average operating time being between one and two days until a refuel is required.

2. The Auger

The stove is motorized with electricity and a metallic spiral structure component called the auger transports the pellets into the burn pot, the speed of the auger dictates the stove’s temperature.

3. The Burn Pot

The burn pot is then ignited and the pellets begin to burn and produce heat, as these kind of stoves are more compact they produce a more intense flame and as a result more heat. The leftover ash produced from the burning process is then deposited into the ash pot ready to be emptied.

4. Heat Exchanger

By transferring clean, hot air produced by the stove to your living space via a blower means the room is heated efficiently and effectively. It achieves this through convection, which is the transmission of heat through the effect of cool air and hot air currents.

The convection blower draws cool air from the room, passing it over the hot flames of the fire resulting in a more intense flame and heat, allowing the pellets to burn evenly and efficiently.

This heated air is then directed over a heat exchanger, which is designed to transfer clean air into your home via the room blower. This is perhaps one of the key components of the pellet stove, and the combination of the heat exchanger and forced combustion air design allows pellet stoves to achieve overall heating efficiencies between 70 and 80 percent.

5. Venting

A natural consequence of combustion is the production of exhaust fumes which if inhaled can be detrimental to health, for example, carbon monoxide can kill.

For this reason, pellet stoves are equipped with a venting system to isolate and transport these toxic fumes from your home safely.

This is usually located at the back of the stove and can be joined with a chimney or through another appropriate system.

6. Thermostat

Wood pellet stoves are controlled using a thermostat, as previously mentioned the auger speed dictates how hot the stove becomes as it feeds the pellets into the burn pot within the combustion chamber.

This is a very precise science, for example, pellets fed into the stove at ten pounds (0.453 kilograms) per hour generates a medium flame that is prolonged.

The great news about pellet stoves is that they are carbon neutral, meaning the environmental protection agency does not monitor their use as they do with wood burning stoves.

For instance, wood emits 0.00612 pounds per kilowatt-hour of CO2. While pellets emit 0.035 pounds of CO2 per kilowatt-hour, meaning they are by far the eco-friendly alternative.

There are two major types of pellet stove called free-standing and insert stoves. The one that is most appropriate for you depends on your current fireplace.

For instance, if you have a fireplace, then you would probably choose an insert that slots nicely into the firebox and vents up your chimney. However if not then you would select a free-standing unit with its own venting system.