Ok, so, you’ve purchased your sauna heater. What now? If you are constructing a new sauna, it’s important to have everything ready and in place for the installation of your new sauna heater.
First, it’s important to confirm that you have chosen the correct size for your sauna. While manufacturers sometimes vary slightly in their sizing, a good rule of thumb is 1,000 watts (1 kilowatt) for every 50 cubic feet of sauna. For example, if your sauna is 6′ wide x 7′ long x 7′ ceiling height, you would calculate your cubic footage as follows:
6′ x 7′ x 7′ = 294 cubic feet. 294 divided-by 50 equals 5.88 (Minimum kilowatts needed.)
Of course, always go by the sizing of your particular model. Usually, going an extra kilowatt is not a bad idea, either. There are also other factors to consider, such as when the sauna heater is going in an outdoor sauna. When you factor-in heat-loss and additional load on the unit, outdoor saunas require more “horsepower.” It’s good to consult with your sauna dealer who can help you with sizing an outdoor sauna for your geographic location. Also, size ratings are based on the assumption that your sauna is well-insulated, generally with a minimum of R-24 in the walls and R-30 in the ceiling.
Another thing to consider is where the unit will be mounted. It’s important to read your sauna heater’s installation manual in detail prior to the actual installation. Be sure and factor-in required clearances from walls and benching, and allow extra room for a heater guard/heater fence for safety. It’s also not a bad idea to locate your sauna heater in a convenient spot where you can easily adjust the bathing-time, temperature and/or ladle water onto the hot stones. Manufacturers usually recommend that you install wood blocking inside of the wall behind where the sauna heater will mount for added support. Also, be sure that your electrician uses the proper high-temperature rated electrical wiring inside of the necessary conduit for your sauna heater and lighting. Make provisions for installing temperature sensors and wall control wiring (when a wall control is used), prior to covering up the wall with your sauna’s vapor barrier and wood paneling on the inside, or sheetrock, etc., on the outside. If you are installing a wood or gas sauna heater, be sure to plan-ahead for ventilation and exhaust, both of which are very important.
Ventilation is extremely important and often overlooked when a sauna is constructed. It is less about moisture with a sauna, than providing fresh air. The most ideal place to locate an air vent is directly below the sauna heater and approximately 4″ from the floor. It’s good to have an adjustable exhaust vent at the opposite of the sauna, as far from the intake as possible. The height is a matter of preference, but can be as low at 24″ from the floor, or as high as 6″ from the ceiling. Adjusting this vent controls the amount of flow through the room. Ideally, your venting should allow six full air exchanges per hour.
Finally, let’s talk candidly about the installation of your sauna heaters. Many of us pride ourselves on being “do-it-yourselfers.” Taking this approach to wiring your sauna heaters without the proper knowledge can damage your equipment, your property, and can even result in the injury or death to those using the sauna. Improper installation of your sauna heaters, also voids your sauna heater’s warranty. Experts always suggest hiring electricians when installing sauna heaters. Under normal conditions, it is relatively inexpensive to have an electrician install your sauna heater. Isn’t it worth the piece of mind knowing that your sauna heater has been properly installed and is safe?
Finally, when your sauna heater is installed, the correct placement of the stones is important. First, wash your stones thoroughly. Then loosely place them in the heater as directed by your manufacturer.  With most sauna heaters you place the stones in-between the heating elements. One of the most common installation problems is when these stones are placed inside the sauna heater too tightly. This often causes problems with the heater’s high-limit, which is a built-in overheating safety feature. Always remember that the heater’s stones should be placed loosely within the rock compartment, allowing it to maintain the proper airflow.
The sauna heaters are the engine of your sauna. With a little pre-planning and by following these tips, you’ll enjoy many years of trouble-free sauna usage!
