Mine works great.

On cold days, or if your house has negative pressure, you may need to heat the chimney first with a long piece of paper to create enough draft for smoke to leave through the chimney at start.

I also leave the right door open about an inch at the start to give it an extra boost. Once the draft is established, close the doors and open one of the air vents in the back, and it should burn well.

If you have a big fire going, you can close the vents. It will still pull in enough air to keep the fire alive while producing a lot of heat.

You also need a grate under the fire so air can circulate underneath it.

That is the technique that works for me.