Multi fuel stoves help to increase the amount of heat you can produce in your home when burning wood compared to open fireplaces. Multi fuel stoves also allow you to burn other types of solid fuel, but how can you get the most amount of heat from a multi fuel stove?
To get the most heat from a multi fuel stove:
- Ensure that the fire has been built and lit correctly to provide a bed of hot coals so that larger sized logs can be added to the fire.
- Use hardwood logs over softwood logs when burning wood, and ensure that the wood is dry.
- Keep the stove topped up with fuel, without overloading the stove.
- Ensure that the air vents are correctly positioned to provide enough oxygen to the fire.
I’ve explained how to get the best heat from a multi fuel stove in more detail below, using our own multi fuel stove as an example for how we try to produce the most amount of heat from it.
Build And Light The Fire Correctly
Getting the fire going well to produce a bed of hot coals from the initial bits of wood provides a multi fuel stove with a platform to produce the most amount of heat for the remainder of the fire.
The aim at the start of any fire in a multi fuel stove is to get the fire going as quickly as possible, and to bring the stove up to a temperature where larger pieces of fuel can be added to the fire. The larger pieces help the stove produce the most amount of heat.
Creating a hot platform inside a multi fuel stove requires building a fire with newspaper and dry small bits of kindling so that it can burn down quickly to a hot bed of coals.
Larger logs will catch alight much more easily thanks to a hot bed of coals, and you’ll struggle to get a fire going if larger sized pieces of wood are used in the fire too early on.
A fire won’t be producing any significant amounts of heat during its early stages and so it’s best to get to the point where larger logs can be added to the fire in order to produce the best heat.
You can read my more detailed guide to building and lighting a fire in a multi fuel stove here.
Use The Right Fuel
Softwoods such as Pine are best used during the early stages of a fire in a multi fire stove when getting the fire going quickly to be able to add larger sized pieces of fuel.
Softwoods typically catch alight and burn more quickly than hardwoods, and so they are the best type of wood to use as kindling when lighting the fire and when using smaller sized logs to help the stove get up to operating temperature.
Once a bed of hot coals has been produced by a fire (a layer of glowing embers), hardwoods logs such as Oak or Ash should be used.
Hardwoods are typically denser than softwoods and so take more energy to catch alight, but in turn produce the most amount of heat per piece. They can also provide a cleaner burn, which helps to protect your stove and flue from quickly building up with creosote.
If you’re looking to get the most heat from a multi fuel stove, use well seasoned or kiln dried hardwood logs.
Wood with high moisture content will be far less efficient when burning compared to logs with moisture content of the recommended 20% or less. Therefore be sure to only use hardwood logs that have been kiln dried or properly seasoned for around two years. A moisture meter will be able to give you an accurate reading of how dry your wood is.
The downside of using hardwood is that it takes longer to season (dry out) and so can typically be more expensive to buy.
We season our wood under a cover and on a dry platform, with one side left open to the wind to help dry it out. You can find out more information on how we season our own wood here.
Keep The Fuel Topped Up
In general, the more fuel that is being burnt, the more heat the fire can produce.
Therefore, to get the most heat from a multi fuel stove, ensure to periodically refill the firewood back up to the maximum permissible amount for your particular model of stove.
Be sure not to overload your stove with fuel however, as doing so can damage the stove over time due to higher temperature created by the larger amounts of fuel. Check your manufacturer’s guidelines on how much fuel you can put in your multi fuel stove.
Not overloading your stove also helps to prevent any air vents from being blocked, and the multi fuel stove underperforming as a result. If you have any air vents at the back of the stove (example shown below for one of our stoves) then the amount of fuel should never exceed the height of these vents.
Ensure Correct Positioning Of The Air Vents
Another important factor in getting the most heat from a multi fuel stove is how far open the air vents are.
To produce the most amount of heat, a multi fuel stove needs the right balance of oxygen supply to correspond with the amount of fuel being burnt.
As multi fuel stoves can burn a number of different types of solid fuel such as wood and coal, there is typically more controllable air vents found on a multi fuel stove than a wood burning stove. There are two controllable air vents on our multi fuel stove, whereas there is only one controllable air vent on our wood burning stove.
Wood can burn best with a flow of air from above the fire, and so the secondary air vent is typically used to control the rate at which the fire burns, and therefore how much heat is produced. The primary air vent therefore generally remains left on partially open or fully closed for the duration of the fire when burning wood, and doesn’t need to be adjusted.
When burning coal, the primary air vent typically becomes the main vent that controls the fire, as coal burns best with a source of oxygen from below. The secondary air vent is typically left partially open when burning coal to allow any air wash and secondary burn systems to operate efficiently.
I’ve explained primary, secondary and tertiary air in stoves here.
You can find my in-depth guide to air wash systems in stoves here.
Click here for more information on secondary burn in stoves.
To maximize the amount of heat produced by a multi fuel stove, the stove needs the right amount of fuel and a sufficient supply of fresh air. A multi fuel stove with more fuel will therefore need more oxygen to burn as a result.
The air vents on a multi fuel stove therefore need to be open enough to provide the right amount of oxygen required by the fire.
If the vents are too far closed, the fire will be starved of oxygen and can’t burn through the fuel quickly enough to produce the most amount of heat. On the other hand, air vents that are open too much can cause the fire to burn through the fuel too rapidly for processes such as secondary combustion of gases to occur, which in many cases produces more heat than simply burning the fuel itself.
When using our multi fuel stove to burn wood, we leave the air vents fully open when lighting the fire, and once the fire has visibly caught hold of the kindling we:
- Close down the primary air vent (located on the front of our stove) so that it’s left partially open for a small amount of air to be supplied to the fire from below. In some cases this vent can be fully closed without causing a wood fire to go out.
- Partially close down the secondary air vent (located underneath our stove) so that the fire is still being fed with plenty of oxygen from above, without providing too much air that would cause the fire to rapidly burn through the wood.
We then use the secondary vent throughout the remaining duration of the fire to control the heat output. If the fire looks to be struggling, we simply open this air vent slightly.
To get the most heat from a wood fire inside a multi fuel stove, keep the secondary air vent open as much as possible without losing too much heat up the flue.
I’ve explained in more detail here on how to control a multi fuel stove using the air vents.
How To Get The Most Heat From A Multi Fuel Stove
In summary, to get the most heat from a multi fuel stove:
- Build and light a fire in a way that gets the fire going quickly in order to produce a bed of hot coals on which larger pieces of wood can be added to the fire without smothering it.
- Add well-seasoned and dry pieces of hardwood to the fire once a bed of hot coals had been provided from the initial small bits of wood.
- Ensure that the air vents on the multi fuel stove are fully open when lighting, and are partially closed once the fire has caught hold to help control the fire.
- Kept the fire topped up with fuel, without overloading the stove.
- Open the main air vent as far as possible, without causing the heat to be lost up the flue.
This method helps to get the most amount of heat from your multi fuel stove as quickly as possible. Reaching higher temperatures inside your stove isn’t very efficient however, and you’ll be finding that you’re burning through the fuel at a much higher rate.
We have a stove thermometer that came as an optional extra with our multi fuel stove, and the picture below shows how hot our stove got after following this procedure.
You can read more about how hot our multi fuel stove gets in another one of my articles here.
The thermometer reads that the temperature of the stove was running ‘too hot’. If you are trying to get the most heat from a multi fuel stove then this is ok.
On the other hand, if you’re trying to get the most amount of heat out of every piece of fuel, then keeping the temperature of your multi fuel stove within the ‘best operation’ temperature range is more efficient.
If you want to keep your multi fuel stove burning for longer rather than trying to produce the most amount of heat as quickly as possible, click here to read another one of my articles explaining how to do so.
Further Reading
How To Control A Multi Fuel Stove Using The Air Vents
How To Keep A Multi Fuel Stove Burning
How To Build And Light A Fire In A Multi Fuel Stove
Parts Of A Stove Explained With Pictures And Labels
Can You Install A Multi Fuel Stove In An Existing Fireplace?
Things We Had To Consider When Buying A Stove