Harvia WZ115030SP Damper Plate for Wood-Burning Sauna Stoves

The Harvia WZ115030SP damper plate regulates airflow in the smoke pipe of a wood-burning sauna stove. By controlling how much draft escapes up the chimney, the damper reduces the burn rate and keeps more heat in the sauna — more efficient heating and better sauna performance from every load of wood. The stainless steel section installs in the standard Harvia 115 mm smoke path and includes the damper mechanism in a 33 cm pipe length.

Features

• Regulates airflow and draft in the smoke pipe
• Reduces burn rate and minimizes heat loss up the chimney
• Stainless steel construction
• Compatible with all Harvia wood-burning sauna stoves except the Harvia 50
• Limited 2-year warranty (consumer use); limited 1-year warranty (commercial use)

What’s Included

• Damper plate (pipe section with damper)
• Installation and operation manual

Specifications

Compatibility

Fits the 115 mm smoke outlet of Harvia wood-burning sauna stoves (except the Harvia 50) and connects to Harvia WZ smoke pipes and the WHP steel chimney system. Prefer an insulated damper higher in the chimney? See the Harvia WHP270 insulated smoke damper, also at Sauna Marketplace.

Good to Know

What is the difference between this and the WHP270 damper?

The WZ115030SP sits in the non-insulated smoke pipe right above the stove and regulates draft while firing. The WHP270 is an insulated damper for the chimney itself, used mainly to retain heat after the fire is out. Many winter saunas use both.

Can I close the damper while the fire is burning?

Use it to moderate draft, never to shut the flue on an active fire — a fully closed damper on a live fire can push carbon monoxide into the sauna. Close it fully only when the embers are completely out.

Will it fit my stove?

It fits Harvia’s standard 115 mm (4.5″) smoke outlet — all Harvia wood-burning sauna stoves except the Harvia 50.

Designing a Harvia Chimney System

Every part on this page belongs to Harvia’s modular WHP steel chimney system: a 115 mm (4.5″) smoke path inside a 220 mm (8.6″) insulated casing, assembled with slot-and-lock joints. Here is how a complete system comes together:

1. Start with the chimney. For pitched roofs, the WHP1500 kit (1500 mm chimney plus rain cap, tilted rain flange, smoke pipe, and ceiling lead-through set) is the core of the system. For flat roofs and barrel saunas, the WHP1000500 package bundles the chimney with the symmetric roof kit.
2. Connect the stove. Bridge the stove collar to the insulated chimney with 115 mm WZ smoke pipes (20 cm, 50 cm, or 1 m). Add the WZ115030SP damper plate at the stove to control draft while firing, a WZ115120 reducer where pipe sections step down, or the WZ115155 adapter if you are transitioning to 6″ US Class A pipe.
3. Reach your height. Add WHP500 (500 mm) or WHP1000 (1000 mm) extensions. Stay within Harvia’s limits: 5.0 m (16.4 ft) total chimney height, no more than 2.0 m (6.5 ft) above the last support, lateral supports every 3.0 m (9.8 ft).
4. Go through the roof. Choose the roof kit that matches your roofline — WHP-AS for tilted/pitched roofs, WHP-ASSYM for flat roofs and barrels. Replacement rain collars: WHM22 (tilted) and WHM24 (symmetric). Add a snow barrier above the chimney where sliding snow can load the flashing.
5. Seal and control. The WHM25 vapor barrier restores the vapor-tight layer where the chimney passes the sauna ceiling; the WHP270 insulated damper closes the flue after the fire is fully out so the sauna holds its heat.
6. Finish the stove side. Stone-filled covers — WL300 for Legend stoves, WL300PC for Cilindro — absorb radiant heat from the smoke pipe and significantly reduce its required safety distances.

Key clearances and rules: vertical installation only; 100 mm (4″) from the insulated casing to combustibles; 500 mm (stainless) or 375 mm (black) from non-insulated smoke pipe unless shielded; designed for wood-burning stoves in standalone outdoor sauna buildings. Confirm your plan with your local building authority — and if you would like help speccing the system, talk to us; we design these daily.

Shop the Complete Harvia Chimney System

1. Start with the chimney

• WHP1500 Chimney Kit, 1500mm (stainless or black) — the system core
• WHP1000500 Complete Chimney Package for flat roofs & barrel saunas

2. Connect the stove

• WZ Smoke Pipes, 115mm (20 cm / 50 cm / 1 m, stainless or black)
• WZ115030SP Stove-Side Damper Plate (draft control while firing) (this page)
• WZ115120 Reducing Pipe (joins mismatched pipe sections)
• WZ115155 Adapter, 4.5″ Euro to 6″ USA (hybrid Class A transitions)

3. Reach your height

• WHP500 Chimney Extension, 500mm
• WHP1000 Chimney Extension, 1000mm

4. Go through the roof

• WHP-AS Roof Accessory Kit for tilted / pitched roofs
• WHP-ASSYM Roof Accessory Kit for flat roofs & barrel saunas
• WHM22 Replacement Rain Collar, tilted roofs
• WHM24 Replacement Rain Collar, flat roofs & barrels

5. Seal and control

• WHM25 Chimney Vapor Barrier (seals the ceiling penetration)
• WHP270 Insulated Smoke Damper (retains heat after firing)

6. Finish the stove side

• WL300 Smoke Pipe Cover for Legend stoves (cuts clearances)
• WL300PC Chimney Cover for Cilindro stoves (cuts clearances)