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Description
The Harvia M3 SL is a 16.5 kW wood-burning sauna stove that you load from an adjoining room. The stove heats the sauna while its glass door gives the changing room or lounge the glow of a fireplace. It suits saunas from 212 to 459 cubic feet.
Through-wall loading
Loading wood from outside the sauna keeps bark and ash off the sauna floor, and the fire warms the adjoining room at the same time.
Build
It is made in Finland, with a cast-iron framed glass door that lets you check the fire at a glance. The stone space holds up to 66 lb of stones. The manufacturer listing states stones are sold separately.
Other M3 models
The Harvia M3 loads from inside the sauna, and the M3 package includes a chimney kit and shielding.
Specifications
- Model: WKM3SL
- Output: 16.5 kW
- Room volume: 212 to 459 cubic feet
- Loading: through the wall from an adjoining room
- Door: cast-iron framed glass
- Stone capacity: up to 66 lb, sold separately
- Made in Finland
Related
Browse sauna heaters, or use our sauna size calculator to work out your room volume before choosing an output.
Specifications
| Model | WKM3SL |
|---|---|
| Output | 16.5 kW |
| Room volume | 212 to 459 cubic feet |
| Loading | through the wall from an adjoining room |
| Door | cast-iron framed glass |
| Stone capacity | up to 66 lb, sold separately |
| Details | Made in Finland |
Specifications from the manufacturer. Dimensions are approximate.
Shipping
We ship to the 48 contiguous U.S. states and Washington, DC. Your shipping cost is calculated at checkout and shown before you pay.
You will get an order confirmation right away and tracking by email when your order ships. Questions about timing for a specific item? Call (945) 280-3243 or email support@restoresuite.com before you order.
Delivery
Large items such as saunas, hot tubs and cold plunge tubs usually ship by freight. The carrier contacts you to schedule delivery. Please check the packaging and note any damage on the delivery receipt before you sign, then tell us within 48 hours so we can resolve it for you.
Before delivery day, measure doorways and hallways along the path to the install spot, and confirm the electrical requirement on the Specifications tab.
Warranty
30-day limited warranty against manufacturing defects
If this item has a manufacturing defect within 30 days of purchase, contact us with your order number and a photo or video of the issue and we will make it right.
Reviews
What delivery looks like
Learn more from Harvia
Manuals and documents
Official Harvia documents for this model. Opens as a PDF.
Why this heater
A Finnish 16.5 kW Harvia wood sauna stove you load through the wall from the next room, for saunas up to 459 cubic feet.
- Loads from the adjoining room, keeping debris out of the sauna.
- 16.5 kW for 212 to 459 cubic feet.
- Glass door adds fireplace glow next door.
- Made in Finland.
Key specs at a glance
The numbers to check before you order. Full details are on the Specifications tab.
- Stone capacity
- up to 66 lb, sold separately
Before you buy: what to know
Based on the manufacturer's specs, manuals and our research.
- The M3 SL loads through the wall from an adjoining room, so the stove heats the sauna and the glass door gives the next room a fireplace glow. It suits 212 to 459 cu ft.
- Stones are sold separately; it holds up to 66 lb. Order them with the stove so you are not waiting on stones at install.
- If you would rather load from inside the sauna, the standard Harvia M3 has the same 16.5 kW output, includes stones and costs $700 less.
- Clearances to walls, ceiling and benches come from the installation manual, and a wood stove also needs a proper chimney run. Check local code and your insurer before you build around it.
- It usually ships within 1 to 3 business days and arrives in about 5 to 10 business days, so it can be on site before your build is finished.
Not sure this is the right fit? Ask us or call (945) 280-3243.
Compare Harvia models
Swipe to compare 4 models
| Model |
 Harvia Pro 20 24kW Wood Sauna Stove Package with 22L Water Heater & Chimney
From $5,503.00 |
 Harvia Virta Pro HL Electric Sauna Heater with Xenio CX45 & Power Unit
From $6,299.97 |
 Harvia Pro 20 SL 24.1kW Through-Wall Wood Sauna Stove
$2,199.97 |
 Harvia Club Deluxe Stainless Steel Electric Sauna Heater
From $3,799.97 |
|---|---|---|---|---|
| Stone capacity | – | – | – | – |
Common questions
How does through-wall loading work?
What size sauna does it heat?
Are stones included?
Where is it made?
Choosing the right setup can be tricky. We are here to help.
Tell us your space, power and how you plan to use it, and we will help you compare models honestly, including whether this one is the right fit.
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Honest guidance
Free guides and calculators for sizing, running costs and safety, so you can decide with real numbers. See the research
