The heating process of a traditional sauna relies on the complex interaction between the stove, stones, and air. This process, known as 'convectional heating,' creates the characteristic warmth and atmosphere of the sauna. When the sauna stove is activated via the control panel and thermostat, its high-power heating elements (resistors) quickly glow red. These hot resistors then begin to heat the pile of special sauna stones they are in direct contact with and surround. The stones, typically volcanic rocks specially selected for their ability to store high heat, act as a 'heat battery,' absorbing heat and reaching a stable temperature. Cold room air entering through the vents at the bottom of the stove passes through these hot resistors and stones. The heated air expands, becomes lighter, and rises from the top of the stove, spreading throughout the room. This heated air hits the ceiling, moves towards the opposite wall, cools as it descends, and re-enters the stove from below. This continuous natural air circulation continues until the entire room reaches the desired high temperature, ensuring uniform heat distribution.

Infrared sauna heating systems, unlike traditional saunas, do not primarily aim to heat the air; instead, they use air as a medium. An infrared sauna contains special heating panels made of carbon or ceramic materials. These panels convert electrical energy into 'far infrared' radiation at a specific wavelength that the human body can easily absorb. These rays, like invisible light, travel through the air and penetrate the first solid object they encounter—your body. This technology is similar to how the sun warms your face on a cold day; even if the air temperature is low, the rays directly penetrate your skin and muscle tissue, warming you from within. This allows infrared saunas to provide deep and effective sweating even at lower ambient temperatures than traditional saunas.