{"product_id":"finnleo-magma-sauna-heater-magma-21-0-kw-480v-3ph","title":"Finnleo Magma 21.0 kW (480V 3PH) Sauna Heater","description":"\u003ch2\u003eFinnleo Magma 21.0 kW (480V 3PH) Sauna Heater\u003c\/h2\u003e\n\n\u003cp\u003eThe \u003cstrong\u003eFinnleo Magma 21.0 kW (480V 3-Phase)\u003c\/strong\u003e is a commercial-grade, floor-standing electric sauna heater built for large traditional sauna rooms that demand serious, sustained heat. As the entry point into Finnleo's Magma series, the 21.0 kW model is engineered to heat sauna rooms from \u003cstrong\u003e780 to 1,270 cubic feet\u003c\/strong\u003e, making it the go-to choice for substantial home saunas, spas, gyms, and small commercial installations that need more than a standard wall-mounted heater can deliver.\u003c\/p\u003e\n\n\u003cp\u003eManufactured by Sauna360 under the Finnleo brand, the Magma combines high-output heating elements with a large rock bed to produce the deep, penetrating heat and rich, voluminous löyly (steam) that define an authentic Finnish sauna experience — even in oversized rooms.\u003c\/p\u003e\n\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eCommercial floor-standing heater with 198 lb (approx.) rock capacity\u003c\/li\u003e\n\u003cli\u003eSized for sauna rooms from 780 to 1,270 cubic feet\u003c\/li\u003e\n\u003cli\u003e21.0 kW output on a 480V, 3-phase electrical supply\u003c\/li\u003e\n\u003cli\u003eRugged stainless-steel outer shroud for durability in high-heat, high-steam environments\u003c\/li\u003e\n\u003cli\u003ePairs with the SaunaLogic2 (SL2-C) commercial control system\u003c\/li\u003e\n\u003cli\u003eRemote control installation capability — mount the control panel outside the sauna room\u003c\/li\u003e\n\u003cli\u003eDoor switch (interlock) compatibility for automatic shut-off and energy management\u003c\/li\u003e\n\u003cli\u003eProgrammable temperature and run-time settings\u003c\/li\u003e\n\u003cli\u003eSauna stones included\u003c\/li\u003e\n\u003cli\u003eAvailable as Heater Only or as a complete bundled package\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eConstruction \u0026amp; Build Quality\u003c\/h2\u003e\n\u003cp\u003eThe Magma is built as a floor-standing unit rather than the compact wall-mounted heaters found in Finnleo's residential lines. Its rugged stainless-steel outer shroud is designed to withstand the demanding combination of extreme heat, moisture, and steam found in heavy-use traditional saunas, ensuring long-term durability in both residential and commercial settings. Internally, the heater is engineered for reliable, high-output performance, supporting the two-or-more-heater configurations often required in very large commercial sauna rooms. All Finnleo heaters are ETL listed, meeting safety standards for installation in the United States and Canada.\u003c\/p\u003e\n\n\u003ch2\u003eRocks \u0026amp; Heating Performance\u003c\/h2\u003e\n\u003cp\u003eThe Magma 21.0 kW holds approximately 198 lbs of high-quality sauna stones, giving it substantial thermal mass. This large rock bed absorbs and radiates heat evenly throughout the room, minimizing cold spots in large sauna volumes, and produces a soft, plentiful löyly when water is ladled onto the hot stones — the hallmark of true Finnish sauna bathing. For continued performance, stones should be inspected and repositioned annually to maintain proper airflow, with full replacement recommended every 2–5 years depending on usage.\u003c\/p\u003e\n\n\u003ch2\u003eSaunaLogic2 (SL2-C) Control System\u003c\/h2\u003e\n\u003cp\u003eThe Magma 21.0 kW is matched with Finnleo's SaunaLogic2 SL2-C control, a commercial-grade control package built specifically for high-use and multi-heater sauna environments. Its features include:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eSleek digital touchscreen interface for temperature display and adjustment\u003c\/li\u003e\n\u003cli\u003eRemote installation capability — the control unit can be mounted outside the sauna room so bathers cannot alter preset temperature or run-time limits, ensuring consistent operation in commercial or shared settings\u003c\/li\u003e\n\u003cli\u003eProgrammable run time and temperature settings for predictable, energy-conscious operation\u003c\/li\u003e\n\u003cli\u003eDoor switch integration — the heater automatically shuts off if the sauna door is opened and left open, supporting both safety and energy efficiency\u003c\/li\u003e\n\u003cli\u003eOptional external, low-voltage on\/off switch for added convenience\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eElectrical \u0026amp; Contactor Box Requirements\u003c\/h2\u003e\n\u003cp\u003eThe 480V, 3-phase configuration of the Magma 21.0 kW requires a single \u003cstrong\u003eCB 17-3 contactor box\u003c\/strong\u003e to safely bridge the low-voltage SL2-C control with the heater's high-power circuits. A separate 120V supply is also required for the control box itself. Because of the power levels involved, installation must be performed by a qualified, licensed electrician in accordance with the heater's installation manual, ensuring correct breaker sizing and wire gauge for a safe, code-compliant setup.\u003c\/p\u003e\n\n\u003ch2\u003eWhat's Included\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eFinnleo Magma 21.0 kW heater unit\u003c\/li\u003e\n\u003cli\u003eApproximately 198 lbs of sauna stones\u003c\/li\u003e\n\u003cli\u003eTemperature sensor\u003c\/li\u003e\n\u003cli\u003eSaunaLogic2 (SL2-C) control unit (on bundled packages)\u003c\/li\u003e\n\u003cli\u003eCB 17-3 contactor box (required for 480V 3-phase operation)\u003c\/li\u003e\n\u003cli\u003eInstallation and operation manuals\u003c\/li\u003e\n\u003cli\u003eFactory warranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eChoose Heater Only if you already have a compatible SL2-C control and contactor box, or select a complete package that bundles the control and the correct contactor box for your 480V 3-phase electrical setup. Rocks are included on every option.\u003c\/p\u003e\n\n\u003ch2\u003eInstallation \u0026amp; Usage Notes\u003c\/h2\u003e\n\u003cp\u003eThe Magma is a floor-standing heater intended for large traditional (non-infrared) sauna rooms and is not designed or sized for small residential saunas — doing so would result in inefficient, overly rapid heating. Proper room construction and ventilation are essential to safe, effective operation. Routine maintenance is minimal: reposition sauna stones roughly once a year to preserve airflow, replace stones every 2–5 years as needed, and wipe down the stainless-steel exterior with a damp cloth using only clean water on the heater — never pool water or chlorinated water.\u003c\/p\u003e\n\n\u003ch2\u003eWhy Buy Finnleo from Us\u003c\/h2\u003e\n\u003cp\u003eFinnleo, built by Sauna360 in Cokato, Minnesota, is one of the most trusted names in authentic Finnish sauna. Every heater is safety-tested and ETL listed for North America, and the SaunaLogic2 ecosystem ties your heater, lighting, and controls into one cohesive, app-ready experience. We are an authorized Finnleo dealer offering full factory warranty coverage (1-year commercial \/ 5-year residential), expert sizing help, and support before and after your purchase. Have a question about fit, voltage, contactor boxes, or lead time? Reach out and a sauna specialist will help you spec it correctly the first time.\u003c\/p\u003e","brand":"Finnleo","offers":[{"title":"Heater Only","offer_id":48385850999025,"sku":"9053-492","price":6705.0,"currency_code":"USD","in_stock":true},{"title":"Heater + SL2-C Wi-Fi Control (60-min) + Contactor Box","offer_id":48385851031793,"sku":"9053-492+SL2C60+CB","price":9010.0,"currency_code":"USD","in_stock":true},{"title":"Heater + SL2-C Wi-Fi Control (24-hour) + Contactor Box","offer_id":48385851064561,"sku":"9053-492+SL2C24+CB","price":9010.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0582\/6386\/3453\/files\/FinnleoMagmaSaunaHeater00.webp?v=1783710571","url":"https:\/\/finnishsaunabuilders.com\/products\/finnleo-magma-sauna-heater-magma-21-0-kw-480v-3ph","provider":"Finnish Sauna Builders","version":"1.0","type":"link"}