The Complete Guide to Stove Fans: How They Work and Which to Choose
Even with a roaring fire lit, are you still feeling the cold in draughty spots and chilly corners in your home? You’ll be pleased to know that a really simple and cost effective solution exists: the humble stove fan.
But there’s a problem. There are so many different types, sizes and designs out there these days, you may be left scratching your head in confusion. This guide will help you to understand what questions you need to ask to find the right stove fan for what you need.
What is a stove fan?
Stove fans (or log burner fans depending on who you ask!) sit on top of your wood burning stove or log burner, and help to circulate warm air around the room. They don’t produce heat themselves; instead, they distribute and make better use of the heat you’re already generating. Stove fans are sometimes described as eco stove fans because they use the heat from your stove to power the fan, rather than mains electricity or batteries.
How do stove fans work?
Now for the science bit. Stove fans work using the ‘Seebeck effect’, where a temperature difference between two sides of a thermoelectric module generates a small electrical current. This powers a built in motor, which turns the fan blades.
When you place the fan towards the back corner of the stove (away from the flue pipe) it draws in cooler air over the cooling fins. This creates a temperature difference between its hot and cool sides to generate the power needed to run the motor, and for the Seebeck effect to actually work.
What is CFM and how does it relate to airflow?
You’ll probably be wondering what CFM means while you’re shopping for stove fans: it stands for cubic feet per minute. This measures how much air a stove fan can move, a higher CFM means a greater volume of warm air is being circulated. Think of it like this, CFM is the measurement, and airflow is what’s being measured.
CFM | Rough guide |
Up to 100 | Lower airflow, suited to smaller rooms and compact spaces such as cottages, studio cabins, tiny homes and narrowboats |
120–160 | Moderate airflow, suited to small to medium sized rooms such as bedrooms and offices |
180–230 | Higher airflow, suited to medium to larger rooms such as master bedrooms and living rooms |
250+ | High airflow, suited to larger rooms and bigger open spaces |
These are rough comparisons rather than fixed room size recommendations. Things like your stove, your room layout and how much air you need to circulate will make a difference. It’s important to note that even high CFM performance won’t move air into other rooms. For large open plan spaces, additional fans and the correct positioning will be needed.
What about size, and the number of blades?
It’s not as simple as saying ‘more blades and bigger size must be the best.’ Stove fans are available with different numbers of blades, but blade count alone isn’t a reliable way to judge performance. The design of the blades and motor also affects how the fan operates, so when comparing models, look at the CFM to understand how much air they can move.
When it comes to the size, larger fans can accommodate larger blades and can be capable of moving more air, but they also need more space on top of your stove. If your stove is positioned inside an inglenook or has limited clearance around the flue, be sure to check out dimensions before choosing a model. Again, looking at the CFM performance is a more accurate way to make your choice.
Want your room to heat up sooner?
A fan with a lower operating temperature can start circulating warm air earlier as your stove heats up. Take our 22cm Two Blade Stove Fan, which starts producing 50 CFM from as low as 65.5°C. Perfect for those chilly winter mornings!
Want to stop heat from getting trapped around your inglenook?
Having all of the heat from your fire concentrated around the inglenook can mean that half of your room still feels quite cold. Something like our 23.5cm Three Blade Stove Fan produces up to 250 CFM, so it can move a high volume of warm air away from your heat source making it a good solution.
Compatibility
Stove fans work for many types of stoves, log burners and fireplaces, but there are some caveats. Since they rely entirely on direct thermal conduction to generate power, they need a flat and intensely hot metal surface to work, so can't be used with double-walled stoves and cool to touch/ insulated models that don't reach the required starting threshold (usually around 50°C to 80°C).
There’s an upper limit too, if the surface temperature gets too high then the thermoelectric motor can be damaged. Most stove fans have a built in safety strip that helps protect the motor by slightly tilting the fan away from the hot surface, but it’s still important to keep an eye on your stove temperature. You can do this with a magnetic stove pipe thermometer, which can let you know when it’s time to move your fan towards the cooler edge of the stove.
Why should I buy a stove fan?
If you already have a stove or log burner in place, this one simple addition can help you to get the best out of it. A stove fan will:
- Maximise the heat that your stove or log burner is already creating
- Reduce the amount of fuel you use by up to 19% (the room reaches a comfortable temperature faster, allowing you to turn down the stove sooner)
- Remain hassle free with no installation, batteries or annoying power cords
- Start and stop automatically as your fire heats and cools
- Run quietly without disturbing you relaxing or watching tv
- Look great on your fireplace adding a stylish finishing touch
