Product Description
External wood heating with a clear bathing space
This product is a separate heater, not a complete hot tub. Installing the heater outside the tub keeps the interior free and makes the firebox accessible from the surrounding technical area. Allow space for loading wood, removing cold ash, water connections and the chimney as well as the heater body itself.
Three outputs and their dimensions
| Output | Drawing reference | Length × width × height |
|---|---|---|
| 22 kW | BFTS50 | 620 × 400 × 670 mm |
| 28 kW | BFTS75 | 870 × 400 × 670 mm |
| 40 kW | BFTS100 | 1,020 × 400 × 670 mm |
The drawings specify a 129 mm flue outlet, 48 mm water connections and a firebox opening of approximately 280 × 300 mm. Confirm the actual pipework, adapters and flue components required for your installation before ordering.
Choose the output for the complete installation
A larger output is not automatically the best choice. Water volume, starting temperature, frequency of use, insulation, cover, pipe length and weather all affect the heating requirement. The available documentation does not establish a reliable tub-volume range for each output or a guaranteed heating time.
Have the chosen heater and the actual hydraulic layout checked together. A short specification stating only litres and kilowatts does not confirm that the connections and circulation will work in the finished installation.
Construction and space beside the tub
The heater has a rectangular stainless-steel body. The current documentation does not specify the exact steel grade or plate thickness for this offer; confirm these if they are material to your project.
The front provides firebox access and the lower ash area, with the flue connection above. Arrange a dry, clear approach for loading and maintenance. The overall space required includes the heater length, connections and installation clearances, not just the dimensions of the metal body.
UK accessories
| Option | Purpose |
|---|---|
| Ash shovel | Removal of ash after the firebox has cooled |
| Chimney guard | Protection against accidental contact near the hot flue |
| Glass door | A view of the fire through the door |
| Thermometer with pressure valve | The listed combined temperature and pressure accessory |
These accessories are separately selectable and are not automatically included. Pipes or chimney parts shown in photographs do not by themselves establish the contents of the supplied package. Check the accepted quotation for every component.
Compatibility and replacement projects
A 48 mm connection diameter alone does not make a replacement compatible. Check connection height and position, water level, adapters, pipe length and the circulation arrangement as a complete system. Send details of the existing tub and heater before choosing a replacement.
The heater needs a stable base suitable for a wood-burning appliance. Validate the final installation plan, chimney arrangement, protection and clearances from combustible materials for the actual site and the appliance instructions. Keep the firebox and connection points accessible.
Filling, circulation and operation
Fill the tub and heater circuit, release trapped air and check the connections before lighting. Never fire the heater without the required water level and water circulation. The installation must allow inspection for leaks and complete drainage of relevant parts when freezing conditions are possible.
Use wood as specified in the supplied instructions and let the heater and ash cool before cleaning. A suitable cover and tub insulation reduce heat loss, but neither establishes a fixed heating time. Keep access to the firebox and chimney clear throughout use.
Water care and winter drainage
When the installation is unused in freezing weather, drain all places where water could remain trapped in the heater or pipework. Salt treatment is not recommended; confirm the permitted treatment with the actual steel specification and heater instructions before use.
Which heating layout suits your project?
Choose an external heater when preserving bathing space and having a separate, accessible firebox are priorities, provided there is room beside the tub for the heater and its connections.
An internal heater occupies part of the bathing area; an integrated heater belongs to a different tub structure. Confirm the selected output, hydraulic compatibility, supplied components and installation plan in the quotation before committing to a layout.
Frequently asked questions
The selected configuration, final drawing and accepted order documents take precedence for the product supplied.
Which outputs are available?
22, 28 and 40 kW, corresponding to drawing references BFTS50, BFTS75 and BFTS100.
What are the dimensions?
The 22 kW model is 620 × 400 × 670 mm; 28 kW is 870 × 400 × 670 mm; and 40 kW is 1,020 × 400 × 670 mm. Allow additional space for connections, safe access and required clearances.
How should I choose the output?
Consider water volume, starting temperature, use, insulation, cover, weather and pipe layout. No universal litres-per-output rule or guaranteed heating time is established for these configurations.
Is the heater stainless steel?
Yes. Confirm the exact grade and thickness for the unit supplied; these details are not specified in the current source documentation.
Does it reduce the bathing space?
The heater body stays outside the tub, keeping the interior clear. It needs its own installation and service space beside the tub.
What are the connection sizes?
The drawings indicate 48 mm water connections and a 129 mm flue outlet. Confirm the pipework, adapters and compatible chimney components for your project.
Are pipes and chimney parts included?
The accepted quotation must list the supplied components. Their appearance in a photograph does not confirm inclusion.
Which accessories can I select on the UK page?
An ash shovel, chimney guard, glass door and thermometer with pressure valve are separately priced options.
Can it replace an existing heater?
Only after checking connection positions, water level, adapters, circulation, pipe layout and the installation space. Matching one diameter is not sufficient.
Can it heat a swimming pool?
References or demonstrations involving pools do not establish universal compatibility. The volume, hydraulic arrangement, materials and water treatment require written confirmation for the actual project.
What must I do before lighting and in winter?
Fill and bleed the tub and heater circuit, check the connections and ensure sufficient circulation before lighting. In freezing conditions, drain all affected parts completely when the installation is unused.
What warranty applies?
The source states a general 24-month warranty, subject to proof of purchase, correct installation and use, the supplied instructions and the full applicable terms.
