I have looked into fans, as you would think having one very hot room in the house with a wood burner in it, the logic would be to use a fan to push the heat out of the room to the rest of the house. Fact a fan will cool air.
If you lay on the floor in the doorway of the room that has the wood burner in it you will feel a cool draft being pulled into the room, if you use a thermometer to see the difference between the floor and the highest part of the room there is a vast difference this is thermal cycling. Thermal cycling will move a huge amount of air. so in answer to the question all a fan will do is cool air and interrupt the natural flow of air.
I would buy one tomorrow if someone can prove they work but I think they are a placebo not as we see a fan moving but its moving without and power supply.
I think the only way a fan would work if one is placed at the top of the door adding to the thermal cycle.
