Finnleo Magma 24.0 kW (208V 3PH) Sauna Heater

The Finnleo Magma 24.0 kW (208V 3-Phase) is a commercial-grade, floor-standing electric sauna heater built for large traditional sauna rooms that demand serious, sustained heat output. A step up in power from the entry-level Magma 21.0 kW, this mid-range model is engineered to heat sauna rooms from 1,150 to 1,550 cubic feet, making it the right choice for large residential saunas, spas, athletic facilities, and commercial installations where standard wall-mounted heaters simply can't keep up.

Manufactured by Sauna360 under the Finnleo brand, the Magma 24.0 kW combines a high-output heating element with a substantial rock bed to deliver the deep, penetrating heat and rich, voluminous löyly (steam) that define an authentic Finnish sauna experience — even in oversized rooms that require significant heating capacity.

Key Features

• Commercial floor-standing heater with 198 lb (approx.) rock capacity
• Sized for sauna rooms from 1,150 to 1,550 cubic feet
• 24.0 kW output on a 208V, 3-phase electrical supply
• Compact footprint: 35"W x 24"D x 28"H
• Rugged stainless-steel outer shroud for durability in high-heat, high-steam environments
• Pairs with the SaunaLogic2 (SL2-C) commercial control system
• Remote control installation capability — mount the control panel outside the sauna room
• Door switch (interlock) compatibility for automatic shut-off and energy management
• Programmable temperature and run-time settings
• Optional external, low-voltage on/off switch
• Sauna stones included
• Available as Heater Only or as a complete bundled package

Construction & Build Quality

The 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 engineered 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 built 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.

Rocks & Heating Performance

The Magma 24.0 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 across 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 (more frequently in heavy commercial use) to maintain proper airflow, with full replacement recommended every 2-5 years depending on usage.

SaunaLogic2 (SL2-C) Control System

The Magma 24.0 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:

• Sleek digital touchscreen interface for temperature display and adjustment
• Remote 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
• Programmable run time and temperature settings for predictable, energy-conscious operation
• Door switch integration — the heater automatically shuts off if the sauna door is opened and left open, supporting both safety and energy efficiency
• Optional external, low-voltage on/off switch for added convenience

Electrical & Contactor Box Requirements

The 208V, 3-phase configuration of the Magma 24.0 kW requires both a CB 17-3 and a CB 18-3 contactor box working together to safely bridge the low-voltage SL2-C control with the heater's high-power circuits. This dual contactor box setup is specific to 208V 3-phase Magma installations (the 480V 3-phase version requires only a single CB 17-3). A separate 120V supply is also required for the control box itself. Given 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.

What's Included

• Finnleo Magma 24.0 kW heater unit
• Approximately 198 lbs of sauna stones
• Temperature sensor
• SaunaLogic2 (SL2-C) control unit (on bundled packages)
• CB 17-3 and CB 18-3 contactor boxes (both required for 208V 3-phase operation)
• Installation and operation manuals
• Factory warranty

Choose Heater Only if you already have a compatible SL2-C control and contactor boxes, or select a complete package that bundles the control and the correct pair of contactor boxes for your 208V 3-phase electrical setup. Rocks are included on every option.

Installation & Usage Notes

The 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 and an uncomfortable bathing experience. Proper room construction and ventilation are essential to safe, effective operation. The Magma requires a 208-volt 3-phase electrical supply plus a separate 120-volt supply for the control box; professional installation by a certified electrician is mandatory to ensure correct breaker sizing and wire gauge. Routine maintenance is minimal: reposition sauna stones roughly once a year (or more often under heavy commercial use) 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.

Why Buy Finnleo from Us

Finnleo, 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.