Inside A Pellet Stove

A pellet stove looks simple from the outside. A metal box. A glass window. A bin on top.

But inside, there are about ten different parts working together. Each one has a job. Let's walk through them.

The Hopper

This is the bin you pour pellets into. Usually it's on top of the stove, sometimes behind it. Holds anywhere from 20 to 60 kg of pellets depending on the model.

A full hopper can keep the stove running for a whole day. Some big ones run two or three days.

The Auger

This is the part doing the actual feeding work.

An auger is a long screw with a motor on one end. As it turns, it pulls pellets out of the hopper and pushes them into the burn pot. A few pellets at a time. Steady drip-feed.

The motor speeds up when the room is cold and slows down when the room is warm. That's how the stove adjusts its heat output.

The Burn Pot

This is the small metal cup where the actual fire happens.

It sits inside the combustion chamber, surrounded by metal walls. Pellets land in the burn pot, catch fire, burn down to ash. The ash drops out the bottom of the burn pot into an ash pan you empty later.

The Igniter

You don't need a match to start a pellet stove.

The igniter is a small electric element, like the wire in a toaster. When you press the start button, it heats up until it's glowing red. The first pellets to land on it catch fire from that heat. After the flame is going, the igniter shuts off.

The Combustion Fan

This fan pulls fresh air into the burn pot to feed the flame, and pushes the exhaust out the vent pipe.

Without this fan, the fire would die. The fan is also what controls how hot the burn gets. More air, hotter fire.

The Heat Exchanger

This is the part that turns burning pellets into warm air.

It's a set of metal walls or tubes that the hot exhaust gases pass through. The exhaust heats up the metal. Cool room air blows over the other side of the metal and picks up the heat.

Some pellet stoves skip the heat exchanger and let the burn pot warm the room directly. Others use the heat exchanger for cleaner, more controlled heat.

The Convection Blower

A second fan, separate from the combustion fan.

This one blows the warm air from the heat exchanger out into your room. It's what makes the warmth spread instead of just lingering near the stove.

The Exhaust Fan

Some stoves count this as the same thing as the combustion fan. Some split them into two fans. Either way, the job is getting the smoke out through the vent pipe.

The Circuit Board

A small computer is hidden inside the stove. It does the actual thinking.

It watches the thermostat. It tells the auger how fast to feed. It controls the fans. It runs the igniter at startup. It shuts the stove down if something goes wrong.

This is why a pellet stove needs electricity. None of these parts work without power.

The Thermostat

This is the part you interact with. You set the temperature you want. The thermostat measures the actual room temperature and feeds that to the circuit board.

The board does the math: room is colder than the setting, so feed more pellets. Room is at the setting, slow the auger down. Room is too warm, almost stop feeding.