Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed vs Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW

The Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed costs $1,416 and the Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW costs $1,595. This comparison covers the full spec sheets of both, the deciding difference between them, and which buyer each one fits.

Prices verified August 2026

How we vet

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Our verdict

The choice between the Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed ($1,416) and the Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW ($1,595) comes down to model. The Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed offers model of M3 SL, while the Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW offers Cozy O 12. The Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed saves you $179; pay the difference for the Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW only if that gap buys a spec you will use.

Prices verified August 2026.

How we vet

Which one is right for you?

It depends on your situation.

Choose the Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed if

Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed: You want model of M3 SL. The Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed also costs $179 less than the Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW.

Choose the Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW if

Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW: You want model of Cozy O 12.

Full specs comparison

Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed vs Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW full spec comparison
SpecHarvia M3 SL Wood-Burning Sauna Stove w/ Exterior FeedCozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW
Price$1,416$1,595
Type··
Heat Type··
Temp Range··
Heat-Up Time··
Capacity··
Dimensions··
Weight99 lbs108 lbs
EMF Level··
Power16.5 KW12kW
Warranty··

Pros and cons

Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed

Pros

    Cons

      Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW

      Pros

        Cons

          Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed vs Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW: common questions

          How much more does the Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW cost than the Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed?

          The Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW costs $1,595, which is $179 more than the $1,416 Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed. Beyond price, the main spec difference is model: the Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW offers model of Cozy O 12, the Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed offers model of M3 SL.

          Is the Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed worth it over the Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW?

          It depends on the spec you need, and we do not name one of these two better than the other. The Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed offers model of M3 SL, while the Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW offers Cozy O 12. The Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed costs $1,416 and the Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW costs $1,595, a difference of $179.

          What is the main difference between the Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed and the Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW?

          The Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed offers model of M3 SL; the Cozy Heat O Sauna Stove Wood Burning Sauna Stove, Up to 18kW offers model of Cozy O 12. That is the deciding spec difference between the two.

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