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EOS

EOS M3 sauna heater

The EOS M3 is a 3 kW heater that EOS rates for saunas of 106 ft³ to 177 ft³. Check it against your room, see how fast it heats and what it needs from your fuse box.

Updated Oct 18, 2026

Output

3 kW

Rooms

106 ft³–177 ft³

Stones

18 lb

Sizes

1

See it in the 3D studioBuilt-in controlsNot sold in Europe & international in this version

Which size fits your sauna?

Your room's effective volume

141 ft³

71 ft³ – 212 ft³

Effective volume = inside volume, plus 1.2 m³ for every m² of glass, tile or stone; × 1.5 for solid log walls (Harvia's rule, used by most planners).

Sizes and specifications

ModelOutputRoom rangeStonesHeat-upPer session
M3 W3 kW106 ft³–177 ft³18 lb50–65 min$0.82

Heat-up and cost are our heat model's estimate for each size in a room at the middle of its range: indoor, insulated walls, 68 °F around the sauna, heated to 176 °F, one hour of bathing, electricity at $0.18/kWh (United States average).

Electrical connection

ModelSupplyCurrentFuse / breakerCable
M3 W1~ 230 V13 A––

Current is computed from the output; fuse and cable are shown where the maker or dealer states them. A licensed electrician sizes and installs the circuit following the heater's manual and local rules.

Where to see it

Prices and availability come from the shop or maker and change; their page is what counts. Shop offers are added as retailers join.

Sources

Other heaters for the same rooms

Questions and answers

What size sauna does the EOS M3 heat?

EOS rates the sizes for these rooms: M3 W 106 ft³–177 ft³. Use your room's effective volume: add 1.2 m³ for every m² of glass, tile or stone, and multiply by 1.5 for solid log walls.

What fuse or breaker does the EOS M3 need?

It depends on the size and your supply: M3 W: 1~ 230 V: 13 A. A licensed electrician sizes the circuit from the heater's manual and local rules.

How long does the EOS M3 take to heat up?

In a well-insulated indoor room at the middle of each size's range, our heat model gives: M3 W 50–65 min to reach 176 °F. Outdoor saunas, glass and cold weather take longer.

How many stones does the EOS M3 take?

As stated by EOS: M3 W 18 lb. Use the stone size the manual specifies and re-stack the stones at least once a year, replacing crumbled ones.