1. Introduction
The BWT Mini Heat Pump is designed to efficiently heat small above-ground pools with a water volume of 2 to 15 m³. This compact and user-friendly heat pump allows you to temper your pool water to your desired temperature, extending your swimming season.
It is engineered for ease of use and quick installation, connecting directly to your domestic power supply and integrating seamlessly into your pool's filtration circuit. The intuitive display ensures straightforward operation, allowing you to set your preferred water temperature with ease.

Figure 1: Front view of the BWT Mini Heat Pump, showing the main fan and digital display.
2. Setup and Installation
The BWT Mini Heat Pump is delivered ready for use, making installation quick and straightforward. Follow these steps for proper setup:
- Placement: Position the heat pump on a stable, level surface near your pool. Ensure adequate air circulation around the unit.
- Water Connection: The heat pump easily connects between your sand filter and the pool's inlet nozzle. Identify the inlet (red) and outlet (blue) ports on the unit.
- Plumbing: Connect the water flow from your filter to the heat pump's inlet (red port) and the heat pump's outlet (blue port) to your pool's inlet nozzle. Ensure all connections are secure and watertight.
- Electrical Connection: Connect the heat pump directly to a standard domestic power supply. Ensure the power outlet is suitable for the unit's requirements and is protected by a Residual Current Device (RCD) for safety.
- Initial Check: Before powering on, ensure all water connections are tight and there are no leaks. Verify that the pool pump is running and water is circulating through the heat pump.

Figure 2: Side view illustrating the red (inlet) and blue (outlet) water connection ports.
The heat pump is designed to be compatible with all common pool chemicals.
3. Operating Instructions
Once installed and connected, operating the BWT Mini Heat Pump is intuitive:
- Power On: Turn on the power supply to the heat pump. The digital display on the unit will illuminate.
- Set Desired Temperature: Use the controls on the display panel to adjust the desired water temperature. Refer to the specific button functions indicated on the unit for increasing or decreasing the temperature.
- Heating Cycle: Once the desired temperature is set, the heat pump will automatically begin to heat the pool water. The unit will operate until the set temperature is reached, then cycle on and off as needed to maintain it.
- Monitoring: The display will show the current water temperature and the set temperature.
The intelligent design ensures the pump cycles less frequently, which not only protects the cooling system but also contributes to a longer operational lifespan of the unit.
4. Maintenance
Regular maintenance ensures the longevity and efficient operation of your BWT Mini Heat Pump:
- Cleanliness: Keep the exterior of the heat pump clean. Regularly remove any debris, leaves, or dirt that may accumulate around the unit, especially on the air intake and exhaust vents.
- Airflow: Ensure that the fan and heat exchanger fins are clear of obstructions to allow for optimal airflow. Blocked airflow can reduce efficiency and potentially damage the unit.
- Water Connections: Periodically check all water connections for any signs of leaks or corrosion. Tighten connections if necessary.
- Winterization: If you live in an area with freezing temperatures, follow proper winterization procedures for your pool and heat pump to prevent damage from freezing water. Consult a pool professional if unsure.

Figure 3: Angled view highlighting the heat exchanger fins, which require regular cleaning for optimal performance.
The unit utilizes R32 refrigerant, which is an environmentally friendly and efficient cooling agent.
5. Troubleshooting
If you encounter issues with your BWT Mini Heat Pump, consider the following common troubleshooting steps:
- No Power: Check the power cable connection, the wall outlet, and your circuit breaker. Ensure the RCD has not tripped.
- Not Heating:
- Verify the desired temperature setting is higher than the current pool water temperature.
- Ensure the pool pump is running and water is flowing through the heat pump.
- Check for any blockages in the water circulation system or air vents.
- Unusual Noise: Inspect the fan for any obstructions. If the noise persists, contact customer support.
- Error Codes: If the display shows an error code, consult the manufacturer's official support resources or contact customer service for specific interpretations and solutions.
For issues not resolved by these steps, it is recommended to contact qualified technical support.
6. Specifications
| Feature | Detail |
|---|---|
| Model Number | 125500854 |
| Dimensions (L x W x H) | 42.5 x 41.2 x 36.7 cm |
| Weight | 24 kg |
| Material | Metal |
| Energy Type | AC_DC |
| Recommended Pool Volume | 2 to 15 m³ |
| Refrigerant | R32 |
| Country of Origin | China |
7. Warranty and Support
Information regarding the specific warranty terms for the BWT Mini Heat Pump is not provided in this manual. Please refer to the product packaging, the retailer's website, or the official BWT website for detailed warranty information.
For technical support, spare parts, or further assistance, please contact BWT customer service or your authorized dealer. Keep your purchase receipt and model number (125500854) handy when contacting support.
You can often find additional resources, FAQs, and contact information on the official BWT website: www.bwt.com





