Electrical Cut Sheet — IKI Pillar 9kW / HUUM UKU

Text or email this page to your electrician before rough-in.

NIGHTJAR SAUNA

Outdoor Saunas & Cold Plunges · Grand Rapids, MI

Electrical Cut Sheet Rough-in & branch circuit spec
Heater
IKI Pillar — 9 kW UL 875
Control
HUUM UKU Wi-Fi Glass
Service
240V · 1-Phase 60 Hz

Branch Circuit — Heater Power Feed

Connected Load 9 kW
Voltage / Phase 240V, single-phase, 60 Hz
Full-Load Current 37.5 A
Overcurrent Protection 50 A, 2-pole breaker — dedicated circuit
Branch Conductors #6/3 w/ ground copper — L1, L2, Neutral + equipment ground
Neutral — Required Powers the UKU control unit (120V L-N) and any 120V aux (lighting). Not optional — module won't run without it.
Equipment Ground #10 AWG copper min. (NEC 250.122, 50A). Separate from neutral — no bonding at heater or module.
Conductor Rating 90°C (194°F) copper. No PVC-insulated cable inside the sauna — thermal embrittlement.
High-Heat Runs Cable run > 1000 mm above floor inside the wall must withstand 170°C / 338°F.
Connection Method Permanent hardwire in seal-tight conduit. No plugs or receptacles inside the sauna enclosure.

Control — HUUM UKU Wi-Fi (Glass)

Switching Capacity Main module switches up to 9 kW direct — no extension box or contactor for this build.
Power Routing Branch feed (L1/L2/N + gnd) lands in the UKU main module at input terminals L1 L2 N. Neutral terminates here — it does not go to the heater. Module output (V/U) feeds the heater: L1, L2 + ground only, 240V. Heater leg carries full load — #6 Cu / 90°C.
Main Module Location Mount in a dry, accessible spot outside the hot enclosure. Not inside the sauna.
Glass Panel Low-voltage panel cable to module (3 m, 4 × 0.34 mm²). Recessed or surface mount.
Temperature Sensor Mounted in sauna per HUUM placement; wired to module. Built-in overheat cutoff (130°C).
Connectivity 2.4 GHz Wi-Fi at the module for HUUM app / remote start.

Install Notes

  • All electrical by a licensed electrician to NEC + local code.
  • Heater feed is continuous-load sized: 50A / #6 covers the 125% rule and voltage drop on long runs.
  • Bond heater and module grounds to provided terminals.
  • Outdoor build — confirm the circuit originates from a suitably protected exterior-rated source and disconnect.

Verify On Site

  • 240V single-phase confirmed at panel (not 208V).
  • Breaker space for a 2-pole 50A.
  • Run length — upsize for voltage drop past ~60 ft.
  • GFCI / disconnect per local AHJ for the outdoor location.
If it's a 208V or 3-phase job — amperage, breaker, and conductor sizing change. This sheet is 240V single-phase only. Flag it before rough-in and pull the revised spec.
NIGHTJAR SAUNA · Grand Rapids, MI · Outdoor saunas & cold plunges
Reference values from IKI (UL 875) and HUUM UKU installation manuals. Provided as a rough-in guide — final design, sizing, and inspection are the responsibility of the installing licensed electrician per NEC and local code. Rev. Aug 2026.