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Specs

Weight	6.3 lbs
Dimensions	8.5 × 19.5 × 2.25 in
Model	WaterEx
Part Number	H3009032
Included Components	Water-heat exchanger, Installation and operation manual, 5-Year limited warranty
Installation Manual	Installation Resources
Residential Warranty	Limited 5-Year Warranty
UPC	4745090279511
Water tank connection	3/4 in NPT male
Material	0.2 in steel, coated with heat-resistant paint
Mounting positions	Rear edge or sides of the stove

Includes

What Is Included

Includes the product and configuration selected above. Hardware, controls, stones, venting, and accessories are not included unless specifically listed.

See How It Fits for required and compatible products.

How It Fits

How This Product Fits the System

What it is used for

A heater-system accessory for the application shown above. Match the model, part number, dimensions, and installation instructions before ordering.

What to plan

Start with the heater, chimney, or control model—not brand alone—then confirm the accessory part number and configuration.
Optional accessories are not required unless the selected product or installation manual says otherwise.
Replacement and installation parts must follow the current system manual, clearances, and local code.

Products that use this item

This item is used by the following products.

HUUM HIVE Wood-Burning Sauna Stove | 13, 17 & 17 LS Optional accessory for the linked product.

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HUUM WaterEx | HIVE Wood Water Heat Exchanger

HUUM water heat exchanger for HIVE wood-burning sauna stoves. Heats water while the sauna is being heated, with 3/4 in NPT male pipes for the water tank. Mounts on the stove’s rear edge or on the sides.

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$211.00

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Built for

HUUM HIVE Wood-Burning Sauna Stove | 13, 17 & 17 LS
The stove family this exchanger is listed against. See the full product and build your package →

What’s included

Water-heat exchanger
Installation and operation manual

What it does

HUUM’s description: “A heat exchanger heats water when the sauna is heated. The heat exchanger is made of 0.2 in steel and coated with heat-resistant paint. The heat exchanger has ¾″ male pipes for connecting the heat exchanger to the water tank. The heat exchanger may be placed on the rear edge or on the sides.”

It uses heat the stove is already producing to warm a water supply during the same firing, rather than running a separate water heater.

Fitting it

For HIVE sauna stoves
3/4 in NPT male water tank connection
Mounts on the stove’s rear edge or on the sides
0.2 in steel, coated with heat-resistant paint

Which stove

The catalog lists WaterEx against the 17 kW HIVE Wood stove and appears under Operating Accessories on the HIVE Wood product page. The water tank itself is a separate item.

Specifications

Model	WaterEx
Part number	H3009032
UPC	4745090279511
Assembled dimensions	8.5 in x 19.5 in x 2.25 in
Water tank connection	3/4 in NPT male
Material	0.2 in steel, heat-resistant paint
Weight	6.3 lb

Common questions

How does a sauna stove water heat exchanger connect to a water tank?

The HUUM WaterEx connects to a water tank through 3/4 in NPT male pipes. HUUM: “The heat exchanger has ¾″ male pipes for connecting the heat exchanger to the water tank. The heat exchanger may be placed on the rear edge or on the sides.” The exchanger ships with its installation and operation manual; the water tank is a separate item.

What does a water heat exchanger do on a wood-burning sauna stove?

A water heat exchanger heats water off the stove's own fire, while the sauna is being heated, instead of running a separate water heater. HUUM's WaterEx is made of 0.2 in steel coated with heat-resistant paint and is designed for HIVE sauna stoves.

Where does the HUUM WaterEx mount on the stove?

The HUUM WaterEx may be placed on the rear edge of the stove or on the sides. It measures 8.5 in x 19.5 in x 2.25 in and weighs 6.3 lb, and The catalog lists against the 17 kW HIVE Wood stove.