145 products · 33 manufacturer documents · 25 contradictions found
Most sauna listings tell you a kW rating and a room size and stop. The questions that decide your project — how many circuits, what clearance, which heater is actually in the kit — are usually left unanswered. We read the manuals, wrote down what they say, and marked every gap as a gap.
No prices, no star ratings, no invented figures. Where a manufacturer is silent, so are we.
2
Harvia counts a square metre of glass as 1.2 m³ of extra room volume and applies a separate ×1.5 multiplier for uninsulated logs. HUUM counts the same square metre as 1.0 m³ and folds logs into that one rule. On a room with a glass wall those two published methods do not agree — so our calculator runs both and shows you the spread instead of hiding it behind one number.
Run both methods40
Every Harvia and Tylö heater in this dataset omits it. That is a defensible choice by the manufacturer — protective device sizing depends on the installation — but it means you cannot plan the circuit from the listing. We leave the field empty rather than calculating a figure from the kW rating and presenting it as theirs.
Why this happens20
They are rarely labelled as such, and adding the circuit ratings together gives a number that describes nothing. We list each supply group separately and never sum them — a heater on two 40 A circuits is not an 80 A appliance, and telling your electrician it is will cost you a day.
What multi-circuit means8
The rest give a brand, a kW figure, or nothing. Since two heaters of the same rating can have different electrical requirements, “6 kW heater included” is not enough to plan around. We record precisely how specific each manufacturer is, and never fill in the model on their behalf.
What’s actually in the boxFilter by output, room volume, mounting, and — uniquely — whether the manufacturer publishes a circuit specification at all.
Barrel, cabin, and indoor kits, sorted by how precisely each one identifies the heater you’re actually buying.
Wattage and circuit documentation, with every EMF claim quoted verbatim and its actual test scope stated.
Not one of the fifteen sauna sites we audited offers this. Blank cells stay blank.
Enter your room once, see what each manufacturer’s own method returns, and see where they diverge.
Sizing, ventilation, permits, insulation, controls — sourced and explicit about the limits of the record.
Every figure here was transcribed from a manufacturer’s own page or manual, with the source and the date it was checked shown on each product. We recorded 994 individual fields as unpublished rather than estimate them, and we found 25 places where a manufacturer contradicts itself.
We do not publish prices, star ratings, review counts, or performance claims, and we have not tested any of these products. We also do not publish wire sizes or DIY wiring instructions — those belong to the product manual, your local authority, and a qualified electrician, in that order.
We earn a commission on some products. We earn nothing on 18 of the brands listed here, including several of the best-represented, and those pages simply send you to the manufacturer. Nothing about what we can earn affects which products appear, how they are ordered, or what the calculator returns.