HUUM UKU Ext Box UKU Extension Box for Heaters over 12kW



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For use with UKU Controls, the HUUM Extension Box is required for all HUUM sauna heaters over 12kW.


  • For use with UKU controls
  • Required for all HUUM heaters over 12kW
  • Light Grey
  • Wall-mounted design
  • Designed, engineered, and made in Estonia
  • Dimensions: 7″ W (178mm) x 4″ D (101mm) x 10″ D (254mm)
  • SGS Listed
  • Limited 5-year warranty (excluding elements)


  • Extension box
  • Installation and operation manual
  • 5-Year limited warranty


Model UKU Ext Box
Voltage 240
Circuit Breaker Amperage 2 x 63
Weight 3.25 lbs
Width 7″ (178mm)
Depth 4″ (101mm)
Height 10″ (254mm)


UKU Ext Box Manual 2022

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