Rail D
Helps guard against accidental contact with the hot heater.
See fit & details →Explore in 3D →
The feeling starts with the stones
A small footprint.
A generous stone bed.
DROP’s rounded basket holds 122 lb of sauna stones. Water meets a broad stone surface, letting you build the steam a ladle at a time. The wall-mounted shape leaves the floor below open and makes the heater part of the room.
Choose it for a compact wall-mounted installation, exposed stones and a separate control panel. Check the room’s adjusted volume and the space around the heater before choosing the output.
Find the right DROP for your room →
01 / Start with the room
The right size changes everything.
Measure the inside of your sauna. Glass, brick and tile increase the volume the heater must serve. These are the current U.S. manual’s ranges at 240 V.
4.5 kW106–248 cu ft30 A breakerChoose this size ↑6 kW177–318 cu ft30 A breakerChoose this size ↑7.5 kW248–389 cu ft40 A breakerChoose this size ↑9 kW283–460 cu ft50 A breakerChoose this size ↑
Account for glass and masonry.
Multiply interior length × width × height in feet. Add 3.3 cu ft for every square foot of uninsulated glass, brick or tile. A glass front can change the heater you need.
Example: a 6 × 5 × 7 ft room is 210 cu ft. Add 20 sq ft of glass and the adjusted volume is 276 cu ft.
Let 3D Studio help you size it.
Enter your room dimensions, explore the DROP and see the controller and accessories together. Selections stay connected to your package.
Have 208 V power or unusual construction? The manual has separate 208 V ratings. Ask us to check your setup.
02 / Build a complete system
Three essentials. Your choice of finish.
1
Your DROP heater
The same sculptural form in four outputs. Choose the model for your adjusted room volume and available electrical supply.
What comes in the heater box?
Heater, mounting plate, reflector, heat diverter with fastenings, element spacers and the model’s element retainer. Install all supplied hardware. Controls, stones and installation cable are separate.
2
HUUM UKU controls
Local control for use at the sauna, or Wi-Fi control for app access. We recommend UKU Wi-Fi Glass; choose the control and finish you want in your package.
New UKU systems supplied here are UKU 4.2. Follow its current manual for the control unit, sensors and remote-start requirements.
Explore UKU controls →3
The right stones
DROP needs 122 lb of 2–4 in sauna stones. The package option supplies four 33-lb boxes: 132 lb to select from when loading the heater.
Choose “I already have” only when you have the compatible component. The package review shows exactly what you are buying.
Heater price and complete-system price are different.
Your live package subtotal includes the choices you make above. Optional extras are added only when selected. Electrical installation, tax and any location-specific shipping are separate.
Review my selected system ↑03 / Make space for the installation
Plan the wall.
Plan the clearances.
The heater with stones weighs 143.3 lb. The wall structure must support it. A licensed electrician must connect the heater and controls.
- Check the exact model’s wall, bench and ceiling distances. Higher-output DROPs need more space from combustible surfaces.
- Mark the mounting plate, cable route and sensor positions before finishing the room.
- A safety rail helps prevent accidental contact. It does not reduce the required clearances.
- For a partly embedded DROP, at least 14¾ in of the heater must remain above the bench. Use the matching Flange D and follow both manuals.
Electrical planning at 240 V
| Output | Current | Breaker | Minimum wire |
|---|---|---|---|
| 4.5 kW | 18.75 A | 30 A | 10 AWG |
| 6 kW | 25 A | 30 A | 10 AWG |
| 7.5 kW | 31.25 A | 40 A | 8 AWG |
| 9 kW | 37.5 A | 50 A | 8 AWG |
Your electrician must verify voltage, circuit, cable type and local requirements. The 240 V ratings above do not apply unchanged to a 208 V supply.
Open the printable installation checklist →04 / See the details
Get to know your DROP.
Watch HUUM’s guides, then use the current manual for your heater’s generation. Older footage can show earlier hardware.
The DROP hardware
A look at the reflector, diverter and element-support components.
Watch on YouTube ↗Know before you buy
Good questions. Useful answers.
What do I need for a new installation?
A DROP sized for your room, a complete compatible UKU control system, 122 lb of suitable 2–4 in sauna stones, and the installation materials specified by your electrician. The heater box includes its mounting and internal support hardware. Review the selected-system list above before ordering.
Which size do I need for a glass-front sauna?
Use the interior room volume plus the adjustment for uninsulated glass, brick or tile: add 3.3 cu ft for each square foot. Compare that adjusted volume with the current sizing ranges above. 3D Studio can help with the calculation; contact us if the construction or power supply needs a closer look.
Can I pour water on the stones?
Yes. Ladle water onto the sauna stones, following the manual’s water-quality and use instructions. Keep the elements covered by correctly loaded stones; do not pour water directly onto exposed elements.
Can I turn it on from my phone?
Choose a UKU Wi-Fi control system for app access. Remote starting requires the safety setup and checks in the current UKU manual, including the door sensor. Check that the sauna is safe and clear before enabling remote use.
Are stones and a controller included in the heater price?
They are separate selections. The package builder adds the selected control system and stone pack to your heater and shows the combined subtotal. “I already have” excludes that component from the purchase.
Does the safety rail let me put a bench closer?
No. Rail D helps reduce accidental contact with the hot heater. It does not replace or reduce the model’s required clearances. Flange D finishes an embedding opening; it does not waive clearances either.
Can DROP be partly recessed into a bench?
Yes, with the matching embedding flange and the arrangement in the current U.S. manual. At least 14¾ in of the heater must extend above the bench surface. Check the full installation drawing before cutting the bench.
How often do the stones need attention?
The current manual calls for a visual inspection after 100 hours of use, or at least annually; rearranging and replacing cracked stones after 200 hours; and replacing all stones after 400 hours. Let the heater cool and follow the manual’s loading instructions. Do not bend or force the elements when loading stones.
How long does it take to heat the sauna?
Room size, insulation, glass, starting temperature, ventilation and the chosen output all affect warm-up. We do not promise a fixed time for every sauna. Size the heater to the adjusted room volume and follow the commissioning instructions before the first session.
What if I already own an older DROP?
Match parts and instructions to the model and generation on your heater label. New-heater hardware and current installation instructions do not establish which parts are fitted to an older unit. Send us the label and photos when asking about replacement parts.
What should I check when the delivery arrives?
Compare the heater, controls, stone boxes and accessories with your order; they may arrive separately. Inspect packaging and parts, keep photographs of any damage, and confirm everything is present before scheduling installation.
What does the warranty cover?
Read the current HUUM limited warranty in the documents below for coverage, exclusions and installation requirements. Keep your order details and equipment labels. Correct sizing, installation and maintenance matter; contact Sauna Marketplace if you need help with a claim.
For you and your installer
The right manual, in one place.
Use the current DROP and UKU manuals together. Match the model and generation before working on an existing system.
Current US/CA Manual - HUUM UKU 4.2 - v1 ↗Current US Manual - HUUM DROP - H1001L08 v8 / content v5 ↗Current HUUM Limited Warranty Terms - v4 ↗HUUM Heating Element Requirements - 2025-12 ↗HUUM Heater and Stone Requirements - 2025-12 ↗HUUM Certificate of Compliance - SGS ↗
Let’s check the details together.
Send your interior dimensions, glass area, available voltage and a sketch of the heater location. We can help you put the right system together.
Ask Sauna Marketplace 844-565-1113HUUM DROP Build your complete systemReview package ↑
Prebuilt
Brushes, Whisks and Body Care
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