Heaters for saunas are usually either electric or wood-fueled. This page offers information on each style.
Electric sauna heaters offer the benefits of convenience and clean operation, without the need for a chimney. In the United States, UL code mandates the maximum temperature attained with an electric sauna heater cannot exceed 194 Fahrenheit (90 degrees Celsius). The same is true in Canada under CSA rules. These maximum temperatures are currently lower than room temperatures allowed in Europe.
Electric heaters currently on the market usually have an outer shell made of stainless steel or prepainted steel. Given the fact that prepainted steel is a baked-on coating which can lift off the substrate over time, and that rust can then form on the steel beneath the painted coating, obviously stainless steel is the better material to choose for your electric heater. When you're planning your room, have a place in mind where the sauna heater is going to go. Usually the closer the heater can be to the middle of the room, the more even the heat distribution will be. There are many sites on the Internet that offer help on how to build a sauna.
Electric sauna heaters are either wall-mounted or floor-mounted. In most cases a wall-mounted heater is preferred in a residential sauna so less floor area is occupied. Commercial heaters are usually floor mounted due to their larger size and the greater weight of the rocks they can accommodate.
Electric sauna heaters in residences are not allowed to run more than 1 hour without having to be reset. Traditional heaters have rocks that you can pour water onto with a ladle. This will raise the humidity to promote sweating.
In more recent times another type of heater has come onto the market, the infra-red heater. Strictly speaking, the infrared design is not really a sauna heater. In fact, most Europeans scoff at infrared manufacturers using the word "sauna" with their heater.
The infrared heater warms the surface it is pointing to, not the surrounding air. Consequently there is no respiratory benefit. Because the Internet is largely ungoverned, the term "sauna heater" has been loosely used to describe these heaters. We've noticed in recent months some companies selling these heaters are no longer using the term "sauna heater" and now sell them as "heat therapy units", a term much more accurate in our opinion.
Wood fueled heaters
Wood-fueled heaters are not subject to the same restrictions as traditional electric heaters. There is no limit to the maximum temperatures you can operate these - within reason. However, be aware wood-fueled sauna heaters may not be approved for use within your home because of not having a UL or CSA classification and may affect your insurance, so be aware of this before you purchase a wood heater.
Wood-fueled heaters are often chosen to heat a detached, separate sauna building, such as on pool decks. People also choose wood fueled sauna heaters to heat saunas in their cabins or outbuildings in remote areas that don't have 220-240 volt power.
Wood fueled heaters require no electricity to operate. Installing a chimney and maintaining proper clearances from nearby surfaces, are all that is required.
On most wood heaters the exit flue can be switched by the consumer at time of installation from a rear exit to a top exit depending on your preferences and room layout.
Some of the better quality wood heaters on the market have a porcelain finish on the outside. This finish is tough and durable, remaining attractive through years of use.
Given that wood heaters can heat a large room easily, and to a higher temperature than electric heaters without needing electrical wiring for 220-240 volts, perhaps a wood heater will fit your needs.
For residential use in the United States and Canada, sauna controls are required to have a maximum 1-hour timer, plus a thermostat for temperature control. These can be either mechanical or digital controls. Commercial saunas can run longer than the 1 hour residential restriction, providing there is an attendant on the premises that checks on occupants. The attendant can often simply look through the glass door that is required in most commercial locations to verify the sauna is operating without difficulties. (See our door section for more information).
Sauna controls are sometimes mounted directly on the electric heater in the case of residential heaters. Some suggest this is a cost-saving measure by the heater manufacturer, and we feel this configuration leads to other consumer issues.
We advocate sauna controls being in their own box, operated from outside of the sauna on either side of the door. From here the controls are not exposed to heat or water. They are also easier to read from outside the sauna where you can still wear glasses and generally the lighting is brighter to read the settings.
Sauna heater guard
NOTE: Sauna heater guards are mandatory for all sauna heaters for personal safety. If you are purchasing a heater only, be sure that the replacement heater fits properly within your existing heater guard.
If the heater you're purchasing is for a new installation, you must construct your own heater guard or purchase one as a separate item.
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