Instruction Manual

Winnerwell®  Wood Burn Stainless Steel Hot Tub and Pool Water Heater

■ WARNING

◆ Please read this entire manual carefully before assembling and using a Winnerwell® heater. Keep children, furniture, fixtures, and all combustible materials away from any heaters.

◆ Failure to follow the instructions in this manual may result in property damage, serious injury, or even death. For your safety and protection, please read and follow all instructions carefully.

The Winnerwell® Hot Tub Water Heater is a precision-engineered, high-efficiency heater designed specifically for hot tubs. It operates on the thermosiphon principle, where hot water rises and creates low pressure, naturally drawing cooler water from below.
This design eliminates the need for a pump or electricity, allowing external placement of the heater while efficiently warming the tub. A key advantage is that it frees up space inside the tub, enabling the use of a smaller model for enhanced convenience.
Engineered for maximum efficiency, the double-wall stainless steel water jacket surrounding the firebox serves as a highly effective heat exchanger, ensuring optimal heat transfer and performance.

■ Specification

SKU	910249 (L-Size)	910248 (XL-Size)
Name	Winnerwell® Wood Burn Stainless Steel L-sized Hot Tub and Pool Water Heater	Winnerwell® Wood Burn Stainless Steel XL-sized Hot Tub and Pool Water Heater
Material	AISI304 Stainless Steel	AISI304 Stainless Steel
Firebox Dimension (Diameter × Length)	380 mm×700 mm/15 in×27.6 in	460 mm×765 mm/18.1 in×30.1 in
Heater Body Dimension (Diameter × Length)	600 mm×800 mm/23.6 in×31.5 in	700 mm×900 mm/27.6 in×35.4 in
Assembly Height	3820mm/150.4in	3930mm/154.7in
Chimney Pipe Diameter	120 mm/4.7 in	120 mm/4.7 in
Net Weight	Approx. 35.8 kg/78.9 lb	Approx. 44.8 kg/98.8 lb
Heating Volume	10 m³	20 m³
Connection Pipe Outer Diameter (Water Inlet & Outlet)	51 mm/2 in	51 mm/2 in
Thread Type (Water Inlet & Outlet)	RC 1 1/2	RC 1 1/2
Recommended Usage	Small to medium hot tubs and pools	Large hot tubs and pools

■ Part Details

Heater Body×1	Grate×1	Ashtray×1	Safety Pressure Rod×2
Clamp×1	Temperature & Pressure Gauge×1	Spark Arrestor×1	Chimney Pipe×5

■ Heater Assembly Steps

※It is recommended to connect the heater to the hot tub/pool first, then proceed with assembling the heater.

1. Check Before Assembly

Ensure all parts are present and undamaged. Wear gloves to prevent injury.

2.  Install the Pipes and Spark Arrestor Connect the chimney pipes and attach the spark arrestor at the top.
3. Install the Temperature & Pressure Gauge Secure the gauge onto the designated port on the heater body.
4. Install the Safety Pressure Rod Connect the two rod sections and screw them into the rod base on the heater.
5. Install the Clamp Secure the chimney pipe and safety pressure rod with the clamp to ensure stability.
6. Final Assembly Check Verify all components are securely installed before use.

■ Installation Steps for Connecting to a Hot Tub or Pool

1. Position the Heater
   ● Place the heater on a stable, level surface near the hot tub or pool.
   ● If using thermosiphon circulation (natural flow), ensure the heater is below the water level to allow heated water to rise and cooler water to flow in naturally.
   ● If the heater is at the same level or higher, a pump-assisted system is required to maintain proper circulation.
2. Connect the Water Pipes
   ● Attach the inlet pipe at a lower point in the hot tub or pool to draw cooler water into the heater.
   ● Connect the outlet pipe at a higher point in the hot tub or near the surface of the pool, allowing heated water to return efficiently and distribute evenly.
   ● Use well-insulated, large-diameter pipes to reduce heat loss and improve water flow.
3. Secure the Connections
   ● Ensure all pipe fittings are tightly sealed to prevent leaks.
   ● Use clamps to secure the pipes firmly in place, ensuring a stable and durable setup.
   ● If using a pump, install a check valve to prevent backflow and maintain proper circulation.
4. Check for Proper Water Flow
   ● Fill the hot tub or pool to the required level before operating the heater.
   ● If using thermosiphon circulation, check that hot water naturally rises and cooler water flows into the heater.
   ● If using a pump-assisted system, ensure the pump operates smoothly and maintains consistent flow.
5. Final Inspection
   ● Double-check all connections for leaks, blockages, or loose fittings.
   ● Confirm that water flows smoothly before lighting the heater.

■ WARNING

1. For gravity circulation between the heater and the hot tub, the connecting pipes/hoses should not exceed 50 cm. If they are longer, a pump is recommended with a flow rate ≤2000 L/h or adjustable via a valve. To prevent steam buildup and excessive pressure inside the heater, which could lead to an explosion, use a pump with low operating pressure (<1 bar).

2. To ensure smooth water circulation, avoid sharp bends or excessive curves in the connecting pipes, as they can restrict flow. Poor water circulation can lead to steam buildup inside the heater, increasing pressure and posing a risk of explosion.
3. To ensure smooth water circulation in the hot tub, follow these installation guidelines: Water Level: The hot tub water level must be at least 10 cm higher than the heater. Cold Water Inlet Position: The center of the cold water inlet on the hot tub must be at least 15 cm above the ground. Hot Water Outlet Position: The hot water outlet on the hot tub should be at least  5 cm higher than that on the heater.
4. Do not install the connecting pipes at a downward angle, as this can disrupt water circulation, leading to uneven heating, reduced efficiency, and potential steam buildup inside the heater, which may increase pressure and pose a risk of explosion.
5. The diameter of the connecting pipes must be at least equal to or larger than the heater’s inlet and outlet connections.
6. Do not place the hot water connection pipe over the edge of the tub. Doing so may obstruct the proper flow of hot water, disrupting the circulation system. In severe cases, this could lead to excessive pressure buildup inside the heater, causing potential damage or even an explosion, posing serious safety hazards.
7. Do not install valves that could accidentally close the water flow during operation, as this may trap steam inside, causing a pressure buildup in the heater, which increases the risk of explosion and serious injury.
8. Before lighting the heater, ensure it is completely filled with water and that no air remains in the upper section. The heater must be fully vented, with water visibly flowing from the outlet to confirm proper filling.
9. Check for leaks, blockages, or air pockets in the system, as these can disrupt circulation and reduce heating efficiency.
10. Since the heater is equipped with a safety pressure rod and connected to an open pool, the pressure gauge should show no reading, and the temperature gauge should remain below 100°C under normal operation. If the pressure gauge displays a reading or the temperature exceeds 100°C, an inspection should be conducted immediately to check for possible issues such as pipe blockages. The issue must be resolved as soon as possible to prevent potential equipment damage or personal injury.
11. Avoid overloading the heater with wood, as excessive temperatures can lead to boiling water and dangerous pressure buildup.
12. Keep the area around the heater and chimney clear of flammable materials. Ensure proper ventilation to prevent smoke buildup and maintain safe operation.

■ Maintenance & Care

● Regularly clean the firebox and chimney to remove ash and soot, ensuring efficient combustion and proper ventilation.
● Flush the heater and pipes periodically to remove mineral buildup and debris, especially in hard water areas.
● Drain the heater completely if not in use for an extended period to prevent corrosion and freezing damage.
● Store the heater in a dry, well-ventilated location when not in use to prevent rust and extend its lifespan.
● Inspect pipe connections regularly to ensure they remain tightly sealed and free from leaks.
● Use only water pipes that match or exceed the heater’s inlet and outlet diameter to maintain smooth circulation.
● Avoid exposing the heater to prolonged moisture or extreme weather conditions to prevent material degradation.