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Heaters / Harvia

M3 wood-burning sauna stove

Power16.5 kW
Fuelwood
Rated room volume6 to 13 m³
Stone capacity29.9 kg
Controls
Voltage
Phase
Stated amperage

A dash means the publisher does not state that figure. Nothing on this page is estimated.

Specs read from Sun Valley Saunas Harvia M3 page, states 211-460 cubic feet. Page stated ft3, converted to m3 on 2026-08-30. Retailer published.

$969checked 2026-08-30

Sun Valley sale price for the stove without stones. Stones +$100, stones plus chimney kit +$1,487.

Where these numbers came from

Every figure above was read from one page, listed here so you can check our reading rather than take it.

Who it suits, and who should skip it

Suits

  • Six person cabins, big glass and shed conversions: the room classes where mid-size stoves top out.
  • Sites without a practical 240 volt run, and buyers who want the ritual of a fire with their heat.

Should skip it

  • A small room. Oversizing wastes panel capacity and reaches temperature before the stones do their work.
  • Anyone unwilling to deal with a flue, local solid-fuel rules and a woodpile. The electric column exists for a reason.

How it sits in the field

Its own published numbers say where it sits among the heaters we track. At 16.5 kW it sits above the 8 kW median of the heaters we track. Its published range spans 7.0 cubic meters, a wider window than the median, which gives a room more margin to land mid-range. The stated stone load of 29.9 kg sits below the 55 kg median of the models that publish one. Each comparison counts only the records that state the figure involved, and the arithmetic reruns on every build.

What the publisher states, and what it does not

Of the 9 facts we try to verify on every heater, the linked pages state 5 for this one.

Not published: the control type, the voltage, the phase, a stated amperage.

Typical documentation for a sauna heater. The stated fields carry the comparison and the gaps stay visible above.

Common mistakes with this class

Buying at the edge of the rated range

Heater makers publish a volume window and their own guidance says to land in the middle of it. A room at the top of this range heats slowly and runs the elements harder than a size up would.

Measuring the room and stopping there

The makers size stoves against effective volume, which counts glazing and uninsulated surface on top of the tape measure. A big window can quietly move the answer a class up.

Forgetting the flue in the budget

The stove price is not the installed price. Chimney sections, roof flashing and clearances are their own line, and local rules on solid fuel stoves vary too much to assume anything.

Closest alternative on power

HIVE 15 kW is the nearest tracked heater by power rating, though it burns nothing: it is electric where this one is wood fired.

This modelHIVE 15 kW
Power16.5 kW15 kW
Fuelwoodelectric
Rated room6–13 m³15–23 m³
Voltage240 V
Price$969

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