How do you choose the right wood-burning heater?
Choosing the right wood-burning heater for your sauna can feel like a big decision, but it doesn’t have to be overwhelming. The good news is that Harvia is here to help you make the right choice, so you can enjoy your sauna experience with complete confidence. Whether you’re looking for the perfect size, design, or steam, we’ll guide you through the key factors to consider in selecting the ideal heater for your needs. With the right heater, you’ll enjoy the perfect sauna experience, tailored to your preferences. Let’s explore the most important things to keep in mind when choosing your wood-burning sauna heater.
A checklist for the buyer of a wood-burning heater
Estimate your sauna size
Check installation requirements
Review local regulations
Choose the heater with the right design and features for you
Decide on your preferred steam experience
Plan for installation and maintenance
Remember: If you have any questions about the right Harvia wood-burning heater for you, contact your local Harvia dealer. They are trained in helping customers choose the right heater for them, and can help with matters involving installation, use and maintenance.
Consider the size of your space
The size of the sauna you want to heat is one of the most important factors when choosing a wood-burning heater. If the heater is too small, it will struggle to heat the space efficiently, putting excessive strain on it and shortening its lifespan. Conversely, a heater that's too large can create an uncomfortable environment and may cause premature wear on both the sauna structure and the heater.
Start by measuring the volume of your sauna. This helps determine the appropriate heater size for your sauna. To calculate the volume of your sauna, multiply the length, width, and height (measured from the highest point of the ceiling if it's sloped). You can use our Harvia Sauna Calculator to help you.
Insulation also affects heater efficiency – a well-insulated sauna may allow for a smaller heater. If your sauna is outdoors, you’ll need to consider local weather conditions and how they impact heating. If you live in a colder climate, you'll need a heater with a larger capacity to compensate for the additional heat loss to the outside environment.
Remember safety distances
When selecting a wood-burning heater, it's not just about choosing the right heating capacity; it’s also about ensuring the heater fits safely within your space and complies with safety regulations. Heaters come in various sizes, designs, and additional features, such as water tanks. Proper installation takes all these factors into account to prevent fire hazards and ensure effective ventilation.
Each heater has its own safety distances, so it’s important to refer to the heater’s datasheet for the exact clearance specifications. Many wood-burning heaters are also available with safety-enhancing accessories, such as protective sheaths and bedding.
Depending on the heater’s protective distances, these accessories can help reduce the required clearances. If your heater is installed on a waterproof tile or wooden floor, using a protective base is essential to prevent heat damage or fire hazards. Additionally, many wood-burning heaters lack adjustable legs, which can complicate installation. The Harvia Legend Protective Bedding, for instance, provides an effective solution to both issues.
Consider local regulations
Before buying a wood-burning heater, it’s important to check local rules about where and how you can install it. In some areas, you may not be allowed to use a wood-burning heater, or you may be limited to where you can install one. Some areas also have rules about emissions or require special permits or inspections. To make sure you're following all the rules, check your local building codes and environmental laws, or ask a local expert or your nearest Harvia dealer if you're not sure.
Explore design and functionality options
When choosing a wood-burning sauna heater, design is an important consideration, as it should complement the aesthetic of your sauna while providing the heating efficiency you need. Harvia offers a wide range of wood-burning heaters with various designs to suit different tastes and preferences.
Some Harvia wood-burning heaters have integrated water tanks, which not only heat your sauna but also provide hot water, offering an energy-efficient solution. A wood-burning heater with a water tank is the perfect choice for a cabin sauna where warm water is not available for washing. As the sauna heats up, the water also warms up and is ready for washing. In heaters with a water tank, remember that the tank must not be empty when heating the sauna, to avoid damaging the water tank. Harvia has a wide offering of wood-burning heaters with water tanks to suit the demands of both small cabins and larger homes.
Consider your steam preferences
Apart from technical considerations, you should also think about the kind of sauna experience you want to have. The steam produced by wood-burning heaters can be categorized as either soft or hard, with the amount of stones in the heater playing a key role in determining this.
Generally, heaters with more stones produce a softer, more abundant steam, creating a gentler atmosphere. On the other hand, heaters with fewer stones tend to produce a harder, more intense steam, offering a more invigorating sauna experience.
Consider whether you prefer a softer steam or a harder one, as this will influence your choice of heater. The stone amount for each heater can be seen on the heater’s datasheet.
Installation and maintenance: Make it easy
Before purchasing a wood-burning heater, it’s important to understand the installation requirements, and that the location of the heater within the sauna is determined by the installation method. Make sure you understand the specifications for installation and whether you need to hire a professional installer. Please note that the heater must always be installed in accordance with the manufacturer's installation and safety instructions.
For more information on installation, contact your nearest Harvia dealer.
Once installed, maintaining your wood-burning heater is key to ensuring it operates efficiently for years to come. Changing the stones once a year, and regularly checking the chimney, and ensuring the air vents are clear are all important steps in keeping your heater running at its best.
Read our article Tips for Maintaining your Wood-Burning Heater for more information.
Need help?
Choosing the right wood-burning heater can seem like a daunting task, but with the right information and support, you can make an informed decision. If you have any questions or would like personalized advice on choosing the perfect wood-burning heater, contact your nearest Harvia dealer.
Cleaner burning of wood
Harvia has been invested for a long time in the product development of wood-burning heaters that promote the cleaner burning of wood. Harvia's GreenFlame heaters act as pioneers for low-emission stoves. In GreenFlame heaters, carbon monoxide emissions from burning wood are 70 percent lower and small particle emissions are about one-fifth lower compared to a heater model of a similar size.
What size wood-burning heater do I need?
The right heater size depends on your sauna’s size. If the heater is too small, it won’t heat the space properly, and if it’s too large, it may overheat the room and waste energy. Measure your sauna’s cubic volume, including ceiling height, and use the Harvia Sauna Calculator as a guide. If your sauna is outdoors or poorly insulated, you may need a more powerful heater to compensate for heat loss.
What type of wood should I use in the heater?
The best wood for a sauna heater is dry hardwood like birch or alder. These burn well, give steady heat, and don’t produce too much smoke. Never burn treated wood, painted wood, plywood, or any wood with glue or chemicals, as they release toxic fumes. For the best results, use dry wood - it burns cleaner and more efficiently.
Do I need a chimney for a wood-burning sauna heater?
Yes, a chimney is required for proper ventilation and safety. It directs smoke and gases out of the sauna while ensuring efficient combustion. The chimney must be installed according to local building codes, which may specify height, materials, and clearance distances. Some regions also have emission regulations, so check whether your setup complies. Harvia offers chimney solutions designed for sauna heaters, making installation easier.
Can I install a wood-burning heater myself?
It depends on your experience and local regulations. While some sauna owners with DIY skills may install a heater themselves, a safe and compliant installation requires knowledge of clearances, ventilation, and chimney setup. In some areas, professional installation is required by law. If you're unsure, consulting a professional is recommended to ensure safety and efficiency.
What’s the best way to store firewood for my sauna?
Store wood in a dry, well-ventilated space, off the ground, and covered to protect it from moisture. Properly seasoned wood improves burning efficiency and reduces creosote buildup.
How often do I need to clean my wood-burning heater?
Regular maintenance is key to keeping your heater running efficiently and safely.
Ash removal – After every use: Empty the ash pan after every use to maintain airflow.
Sauna stone maintenance – Once a year: Check sauna stones once a year or more for cracks and replace them as needed (typically once a year with frequent use).
Chimney cleaning – Once a year: Inspect and clean the chimney at least once a year to prevent creosote buildup, which can be a fire hazard.
Airflow check – Once a year: At least once a year, ensure the air vents and combustion chamber are clear to maintain proper burning efficiency.
Read about other interesting topics
Products
The Harvia Cilindro Wood-Burning Heater – Exceptional Steam for Every Sauna
Products
The easy guide to looking after your sauna stones
Sustainability & Safety
Harvia promotes cleaner burning of wood
Harvia designs and manufactures its products responsibly, with respect for nature and people
