Rated for a bigger room: Saunum Air L 10
Saunum rates it for 283–494 ft³ (about 8–14 m³, our conversion); HUUM rates the STEEL 9 for 8–13 m³ (about 283–459 ft³, our conversion).
HUUM STEEL 9
A 9 kW electric sauna heater from HUUM, rated by the maker for 8–13 m³ (about 283–459 ft³, our conversion). Every figure below is HUUM's own, linked to where it is published.
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Specifications published by HUUM (11)
- Heater output
- 9 kWElectric Sauna Heater STEEL - HUUM
- Room size it is rated for
- 8–13 m³ (about 283–459 ft³, our conversion)Electric Sauna Heater STEEL - HUUM
- Fuel
- ElectricElectric Sauna Heater STEEL - HUUM
- Voltage
- 240 V 2~ or 208 V 2~Electric Sauna Heater STEEL - HUUM
- Breaker / current
- 50 A (240 V), 40 A (208 V)Electric Sauna Heater STEEL - HUUM
- Stone capacity
- 150 kgElectric Sauna Heater STEEL - HUUM
- Controls
- The UKU control system set already includes a black plastic control panel CLASSIC BlackElectric Sauna Heater STEEL - HUUM
- Dimensions
- H 975 mm x W 320 mm x D 320 mmElectric Sauna Heater STEEL - HUUM
- Weight
- 15 kgElectric Sauna Heater STEEL - HUUM
- Warranty
- 3 years (private use); 1 year (commercial use)HUUM Limited Warranty Terms and Conditions (v4, ENG)
- Made in
- EstoniaElectric Sauna Heater STEEL - HUUM
As published by HUUM, read on 2026-09-23. Makers revise their products; check HUUM's current specification before you buy. Figures marked "about" are Saunakivi's unit conversions of the maker's figure.
Before you buy
- Room size. Our heater sizing guide explains how makers adjust the rated room size for glass and uninsulated walls.
If you are looking for more
A longer stated warranty, on at least part of the product: Finnleo Designer-SL2 6.0 kW
Finnleo states: 5 years parts (traditional sauna heater), residential; 2 years in-field labor + 3 years at-factory labor (non-commercial); commercial: 2-year parts-only. HUUM states for the STEEL 9: 3 years (private use); 1 year (commercial use).
Other electric heaters
Harvia KIP80B 8 kW 240VAC
Harvia · electric · 8 kW · rated for 251–424 ft³ (about 7.1–12 m³, our conversion)
Harvia KIP45B 4.5 kW 240VAC
Harvia · electric · 4.5 kW · rated for 100–211 ft³ (about 2.8–6 m³, our conversion)
Harvia KIP60W 6.0 kW 240V
Harvia · electric · 6 kW · rated for 170–300 ft³ (about 4.8–8.5 m³, our conversion)
Harvia Cilindro Half PC90H 9 kW 208V
Harvia · electric · 9 kW
HUUM DROP 6
HUUM · electric · 6 kW · rated for 5–9 m³ (about 177–318 ft³, our conversion)
HUUM DROP 9
HUUM · electric · 9 kW · rated for 8–13 m³ (about 283–459 ft³, our conversion)
STEEL 9: questions answered from HUUM's specification
What is the output of the STEEL 9?
HUUM lists 9 kW. Related question: What size sauna heater do I need?
What size of sauna room is the STEEL 9 for?
HUUM rates it for 8–13 m³ (about 283–459 ft³, our conversion). See our heater sizing guide for how makers adjust that figure for glass and uninsulated walls.
What voltage does the STEEL 9 run on?
HUUM lists 240 V 2~ or 208 V 2~. Related question: Does a sauna heater need 240 V, or will 120 V work?
What breaker or current does the STEEL 9 need?
HUUM lists 50 A (240 V), 40 A (208 V). The installation manual and a licensed electrician have the final word. Related question: What breaker does a sauna heater need?
How many stones does the STEEL 9 hold?
HUUM lists a stone capacity of 150 kg.
How is the STEEL 9 controlled?
HUUM lists: The UKU control system set already includes a black plastic control panel CLASSIC Black.
What warranty does HUUM give on the STEEL 9?
HUUM lists: 3 years (private use); 1 year (commercial use).
Source: HUUM Limited Warranty Terms and Conditions (v4, ENG)
More from HUUM: all HUUM products on Saunakivi.