HUUM UKU Extension Box

HUUM UKU Extension Box – Power Expansion for High-Output Sauna Heaters (Over 12kW)

The HUUM UKU Ext Box is an essential add-on for sauna heaters over 12kW, enabling seamless compatibility with HUUM’s advanced UKU control systems. Designed for larger or commercial-style sauna rooms, this extension box ensures safe, reliable, and efficient operation when pairing high-capacity HUUM heaters with UKU Local, UKU Wi-Fi, UKU Glass, UKU Mirror, or UKU Gold controllers.

Crafted in Estonia with the same minimalist Scandinavian design as the full HUUM product line, the UKU Extension Box features a clean light-grey finish and a compact, wall-mounted design that integrates beautifully into any sauna environment.

Why You Need the HUUM UKU Extension Box

Sauna heaters over 12kW require an additional power module to safely manage electrical load when paired with UKU controllers. The UKU Ext Box:

• Ensures safe and compliant installation
• Enables remote control functionality when paired with UKU Wi-Fi
• Supports heaters up to 18kW
• Provides stable power distribution for demanding sauna setups

If you’re installing a HIVE 15kW, HIVE 18kW, or any sauna heater above 12kW, this extension box is required.

Key Features

• Required for all HUUM sauna heaters over 12kW
• Compatible with all HUUM UKU control systems
• Safe and efficient power distribution
• Compact, wall-mounted design – easy to install
• Light-grey finish for a clean, modern look
• Designed, engineered, and made in Estonia
• SGS Listed for electrical safety
• Durable construction for residential or commercial use

What’s Included

• HUUM UKU Extension Box
• Installation & Operation Manual
• 3-Year Limited Residential Warranty
• 1-Year Limited Commercial Warranty

Technical Specifications