If a vent feels stiff or won’t move freely, it’s almost always a temperature issue rather than a mechanical one — and the fix is simple.

Vents Are Stiff at High Temperatures

The sauna vents are made from the same hemlock wood as the rest of the cabin. Like any wood, it expands slightly as it heats up. At or near maximum temperature, this expansion can make the vent fit more tightly in its frame, requiring noticeably more force to move than when the sauna is cool.

This is normal and not a sign of a defect. You have two easy options:

• Apply a little extra pressure. A firm push is usually all it takes to get the vent moving. Work from one edge if it feels like it’s catching.
• Wait for the sauna to cool. If you’re trying to close the vents after a session, give the cabin 10–15 minutes to cool down. As the wood contracts, the vent will move freely again.

Tip: For best heat-up performance, close all three vents before you start a session and open them once you’re inside. This way you won’t need to fight a hot vent at the start of your session.

Note: If a vent feels physically broken, is cracked, or won’t move at all even when the sauna is fully cooled, contact Plunge Support.