Feature ReviewSeptember 20266 min read
HUUM heaters review: the Drop 6, Cliff 9 and Hive 12, compared
Three Estonian heaters that carry more stone than anything else at their wattage. Which one fits a small room, a tight corner or a big one, and what each needs from your wall before it runs.
HUUM is an Estonian company that treats a sauna heater as an object worth looking at, and two of its designs have won Red Dot awards for it. Underneath the looks, every HUUM carries far more rock than a conventional heater of the same wattage, which is the same principle that makes the Harvia Cilindro throw softer steam than a box, taken further. This is a look at the three sizes a home buyer will meet: the Drop 6 for small rooms, the Cliff 9 for tight ones, and the Hive 12 for big ones, with the wiring and controller costs that the product photos leave out.
Why the stone capacity is the specification
When you throw water on a sauna heater, the steam you get depends on how much stone is hot, and a heater's wattage says nothing about that. Wattage tells you how fast the heater warms the room, while the stone mass decides how much heat it can store and release in one soft wave when the ladle hits it. A conventional 6 kW wall heater holds a tray of stones on top of the elements, perhaps 40 pounds. The Drop 6 packs about 121 pounds into a body the size of a large lantern, the Cliff 9 takes up to 165, and the Hive 12 is an open basket you fill by the sackful. More hot stone means a bigger, wetter, longer wave and a room that rides through a long session without the elements cycling. That is the whole HUUM argument, and it holds before you have looked at the heater.
The Drop 6: the small-room heater with the big stone load
The Drop is the droplet-shaped wall heater, 6 kW, and the one with the Red Dot. It suits small to mid-size home saunas, roughly two to four people, and its whole point is the stone load: around 121 pounds in a compact wall-mounted body, which is why it produces steam a small room usually cannot get. Sauna Kit Co sells it as a package at $3,150 that bundles HUUM's UKU Wi-Fi controller and the stones, so the price is complete apart from the electrician. The UKU is the part to understand: it is a separate wall control that lets you start the heater from your phone, and on the Drop package it is included where the other two sizes leave it as an add-on. Ask about it before you compare prices, because a heater listed without its controller is not the cheaper heater.
The Cliff 9: for rooms with no space to spare
The Cliff is a slim floor-standing 9 kW heater, also a Red Dot winner, built for saunas where the wall and bench layout leaves almost no clearance to give up. Its safety distances are unusually small for the wattage, and an internal air tunnel speeds heat-up by about a quarter. It holds up to 165 pounds of stone. At $2,638 it is the heater to price for a four-to-six person room that a box heater would crowd, and it is the size most often searched for by people building their own room. The UKU controller is sold separately here, so add that to the total.
The Hive 12: when the sauna is a room, not a closet
The Hive is the sculptural one, a 12 kW floor-standing heater with a huge open stone basket, made for large residential and commercial rooms that want serious thermal mass and heavy steam. It costs $2,848, less than the Drop package, because the controller and stones are extra and because there is less engineering in a basket than in a lantern. What it needs is a high-amperage 240V circuit and a room big enough to justify it: put a 12 kW heater in a four-person sauna and you will have a hot room with poor steam, since the elements will cycle off before the stones are through. Our heater sizing guide has the arithmetic; at a rough kilowatt per 45 cubic feet, the Hive wants something over 500 cubic feet.
What every HUUM needs before it runs
Three things sit outside the heater price. A dedicated 240V circuit, hardwired to code by a licensed electrician, and heavier gauge for the Hive. The UKU controller, included with the Drop package and extra on the Cliff and the Hive, without which the heater has no on switch. And the stones, which the Drop package includes and the others do not; at 165 pounds for a full Cliff, that is not a small line. Running cost is the one figure that stays ordinary: a 9 kW heater drawing for the working part of a session costs about what our running-cost calculator says any 9 kW heater does, and the stone load changes how the heat feels rather than what it costs.
Which one to buy
The Drop 6 for a two-to-four person room where you want the best steam a small heater can make and a complete package price. The Cliff 9 for a four-to-six person room, or any room where clearance is the constraint. The Hive 12 for a big room and nothing smaller. If you are choosing between a HUUM and a Harvia Cilindro at the same wattage, the Cilindro is cheaper and a very good heater; the HUUM carries more stone and looks like furniture. Both need the same electrician. Size the heater to the room before you choose on looks.
Common questions
- What size sauna does the HUUM Drop 6 heat?
- A small to mid-size home sauna, roughly two to four people. Size by room volume at about a kilowatt per 45 cubic feet, and push toward a bigger heater if the room is outdoors or has a lot of glass. The Drop's advantage is the 121 pounds of stone it carries at 6 kW, which gives a small room steam it usually cannot get.
- Does a HUUM heater come with a controller?
- The Drop 6 package from Sauna Kit Co includes the UKU Wi-Fi controller and the stones. The Cliff 9 and the Hive 12 are sold as the heater alone, with the UKU controller and stones as separate purchases. The heater does not run without a controller, so price it in.
- HUUM Cliff 9 or Harvia Cilindro: which is better?
- Both wrap far more stone around the elements than a box heater, which is what makes their steam softer. The Cilindro costs less at similar wattage. The Cliff carries up to 165 pounds of stone, has smaller safety clearances, and heats up about a quarter faster through its internal air tunnel. Pick the Cilindro on price, the Cliff on clearance and stone mass.
- What electrical does a HUUM heater need?
- A dedicated, hardwired 240V circuit installed to code by a licensed electrician, on every model. The 12 kW Hive needs a higher-amperage circuit than the Drop or the Cliff. None of them is a plug-in appliance.
- Where can you buy HUUM heaters in North America?
- HUUM sells through dealers rather than direct. Sauna Kit Co carries the Drop, the Cliff and the Hive, and Select Saunas and Sun Valley Saunas stock HUUM alongside Harvia. Our product pages link to the current price at the dealer we track.
Sources
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