Willhi Humidistat – Automatic Humidity Controller for Mist Makers

Set-and-Forget Climate Control for Grow Rooms, Greenhouses & Mushroom Farms

💨 Always Free Shipping on All Products — No Hidden Costs!

Take the guesswork out of humidity. The Willhi Humidistat Controller automatically switches your mist maker and waterproof fan on when humidity drops and off when it reaches your set point — holding your space in a tight range without babysitting. Its high amperage rating drives a single fogger, your fan, and even multiple mist makers at once. Just add a power strip and plug in up to 12 amps, making it the heart of an automated setup for mushroom cultivation, terrariums, grow tents, and more.

✅ Why Choose the Willhi Humidistat?

• Automatic Humidity Regulation – Maintains your preset humidity range effortlessly

• Runs Multiple Mist Makers & Fans – Supports both small and larger mist maker units

• Easy to Use – Simple controls with clear dual LED displays

• Accurate & Responsive – Measures 1%–99% RH with 1% accuracy

• Replaceable Sensor — 2-Year Warranty – Years of reliable service, easy to swap

• Compact & Durable – 1-year warranty on the controller, 2-year warranty on the sensor!

• Data Retention – Settings are saved even after a power loss

📦 What’s Included

• 1x Willhi Humidistat Controller

• 1x 3m (9.8ft) Humidity Sensor Cable

• Free U.S. Shipping on all orders

📊 Specifications

• Humidity Measuring Range: 1%–100% RH

• Humidity Control Range: 1%–99% RH (1% resolution, ±1% accuracy)

• Power Supply: AC 120V or 240V · Consumption < 3W

• Relay Contact Capacity: 10A/240V, 10A/110V

• Dimensions: ~125mm x 91mm x 40mm (4.92" x 3.58" x 1.57")

💡 Pro Tips & Usage

• Make a “J” hook with a rubber band or zip tie on the probe cable so the sensor points upward — this prevents condensation from building on the sensor.

• Use a heavy-duty GFI power strip to connect multiple foggers and fans for smooth operation at higher humidity loads.

• Ideal for mushroom farms, greenhouses, grow rooms, reptile enclosures, and any space needing consistent humidity.

🔗 Pairs With

• Any House of Hydro Mist Maker Kit – the controller automates them all

• Waterproof Fan Kit – switch the fan with the fogger for even distribution

• DIY Humidifier Build Guide – wire it all into one automated system

⚠ Shipping Notes:

• ✅ Free Shipping within the USA on all products.

• 🌍 International customers: shipments outside the USA may incur customs fees, not included in the purchase price.