Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed vs Harvia Pro 20 Wood-Burning Sauna Stove

The Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed costs $1,416 and the Harvia Pro 20 Wood-Burning Sauna Stove costs $1,513. 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 Harvia Pro 20 Wood-Burning Sauna Stove ($1,513) comes down to model. The Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed offers model of M3 SL, while the Harvia Pro 20 Wood-Burning Sauna Stove offers 20 Pro. The Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed saves you $97; pay the difference for the Harvia Pro 20 Wood-Burning Sauna Stove 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 $97 less than the Harvia Pro 20 Wood-Burning Sauna Stove.

Choose the Harvia Pro 20 Wood-Burning Sauna Stove if

Harvia Pro 20 Wood-Burning Sauna Stove: You want model of 20 Pro.

Full specs comparison

Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed vs Harvia Pro 20 Wood-Burning Sauna Stove full spec comparison
SpecHarvia M3 SL Wood-Burning Sauna Stove w/ Exterior FeedHarvia Pro 20 Wood-Burning Sauna Stove
Price$1,416$1,513
Type··
Heat Type··
Temp Range··
Heat-Up Time··
Capacity··
Dimensions··
Weight99 lbs127lbs
EMF Level··
Power16.5 KW24 kW
Warranty··

Pros and cons

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

Pros

    Cons

      Harvia Pro 20 Wood-Burning Sauna Stove

      Pros

        Cons

          Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed vs Harvia Pro 20 Wood-Burning Sauna Stove: common questions

          How much more does the Harvia Pro 20 Wood-Burning Sauna Stove cost than the Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed?

          The Harvia Pro 20 Wood-Burning Sauna Stove costs $1,513, which is $97 more than the $1,416 Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed. Beyond price, the main spec difference is model: the Harvia Pro 20 Wood-Burning Sauna Stove offers model of 20 Pro, 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 Harvia Pro 20 Wood-Burning Sauna Stove?

          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 Harvia Pro 20 Wood-Burning Sauna Stove offers 20 Pro. The Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed costs $1,416 and the Harvia Pro 20 Wood-Burning Sauna Stove costs $1,513, a difference of $97.

          What is the main difference between the Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed and the Harvia Pro 20 Wood-Burning Sauna Stove?

          The Harvia M3 SL Wood-Burning Sauna Stove w/ Exterior Feed offers model of M3 SL; the Harvia Pro 20 Wood-Burning Sauna Stove offers model of 20 Pro. That is the deciding spec difference between the two.

          Neither of these quite right?

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