1. Introduction
This manual provides detailed instructions for the safe and efficient operation of your Sunsun EH-300 or EH-500 series external aquarium heater. This device is designed to maintain a stable water temperature in your fish tank, ensuring a healthy environment for your aquatic life. Please read this manual thoroughly before installation and use.
2. Safety Information
- Ensure the heater is always fully submerged in water when operating.
- Do not operate the heater if the power cord or plug is damaged.
- Always disconnect power before performing any maintenance or handling the heater.
- Keep out of reach of children.
- This appliance is for indoor use only.
- Do not use for purposes other than heating aquarium water.
- The heating rod will stop working if there is no water or insufficient water flow.
- The unit features over-temperature protection and a water cut-off safety mechanism.
3. Package Contents
Upon opening the package, please verify that all components are present and undamaged:
- Sunsun External Heater Unit (EH-300, EH-500, GW-01, or GW-1 variant)
- Power Adapter Plug (EU, AU, or UK type, depending on model)
- Instruction Manual (this document)
4. Product Overview
Familiarize yourself with the components and features of your external heater.
Figure 1: Sunsun External Heater Unit
Figure 2: Digital Display and Control Button
- Indicator light: Illuminates when the heating element is active.
- Digital display: Shows the current water temperature and the set temperature during adjustment.
- Set temperature button: Press to adjust the desired temperature (range 20°C to 35°C). Each press increases the temperature by 0.5°C, cycling back to 20°C after 35°C.
Figure 3: Internal Components and Key Features
- Inlet/Outlet Nozzles: Can connect 16mm/20mm hoses.
- Heating Tube: Explosion-proof glass heater.
- STM8 Series Chips: For smart control and precision.
- Key Features: Precise temperature control, LED display, lack of water stop, overtemperature protection, memory function.
5. Specifications
Refer to the table below for detailed specifications of the available models.
Figure 4: Model Specifications (EH-300 and EH-500)
| Feature | EH-300W | EH-500W | GW-01 300W | GW-01 500W | GW-1 800W | GW-01 1000W | GW-01 1200W |
|---|---|---|---|---|---|---|---|
| Wattage | 300 W | 500 W | 300 W | 500 W | 800 W | 1000 W | 1200 W |
| Voltage | 220-240 V / 50 Hz | 220-240 V / 50 Hz | 220-240 V / 50 Hz | 220-240 V / 50 Hz | 220-240 V / 50 Hz | 220-240 V / 50 Hz | 220-240 V / 50 Hz |
| Hose Compatibility | 16-20mm | 16-20mm | 20-25mm | 20-25mm | 20-25mm | 20-25mm | 20-25mm |
| Application (Tank Length) | 80-120 cm | 100-150 cm | N/A | N/A | N/A | N/A | N/A |
| Unit Length | 31 cm | 31 cm | N/A | N/A | N/A | N/A | N/A |
Note: "N/A" indicates information not explicitly provided for these specific models in the source data.
6. Setup Guide
Follow these steps to properly install your external heater:
- Placement: The external heater is designed to be installed inline with your aquarium's external filter system. It should be placed on the outlet hose from your filter, ensuring water flows through it before returning to the aquarium.
- Hose Connection: Connect the inlet and outlet nozzles of the heater to the appropriate hoses from your external filter. The nozzles are compatible with 16mm/20mm or 20-25mm hoses, depending on your heater model (refer to specifications). Ensure connections are secure to prevent leaks.
- Water Flow: Verify that water flows freely through the heater unit once your external filter is running. The heater requires adequate water flow for proper operation and temperature distribution.
- Power Connection: Once the heater is securely installed and water is flowing through it, connect the power adapter to a suitable electrical outlet.
Figure 5: Example Installation with External Filter
Figure 6: Schematic Diagram of External Heater Setup
7. Operating Instructions
Operating your external heater is straightforward:
- Power On: After installation, plug in the heater. The digital display will show the current water temperature.
- Set Temperature: Press the "Set temperature button" (green button, refer to Figure 2) to adjust the desired water temperature. Each press will increase the set temperature by 0.5°C. The temperature range is 20°C to 35°C. The display will show the set temperature briefly, then revert to showing the current water temperature.
- Heating Indicator: The indicator light will illuminate when the heater is actively heating the water. It will turn off once the set temperature is reached.
- Automatic Thermostat: The heater features an automatic thermostat that will maintain the set temperature by turning the heating element on and off as needed.
- Power Off Memory: The heater retains your last temperature setting even after a power interruption.
8. Maintenance
Regular maintenance ensures optimal performance and longevity of your heater:
- Disconnect Power: Always unplug the heater from the power outlet before performing any maintenance.
- Cleaning: Periodically inspect the heater unit for any algae buildup or debris. Gently clean the exterior with a soft cloth. Do not use harsh chemicals or abrasive materials.
- Hose Inspection: Check the hoses connected to the heater for any blockages or signs of wear. Ensure a clear path for water flow.
- Temperature Sensor: Keep the temperature sensor area clean for accurate readings.
- Storage: If storing the heater, ensure it is clean, dry, and stored in a safe place away from extreme temperatures.
9. Troubleshooting
If you encounter issues with your heater, refer to the following common problems and their solutions. The heater also features a self-check system that displays error codes.
Figure 7: Advanced Features and Error Codes
Error Codes:
| Code | Description | Possible Cause / Solution |
|---|---|---|
| ER | Temperature sensor error | Check sensor connection. If problem persists, contact support. |
| EE | Over-temperature protection activated | Water temperature exceeded safe limits. Check water flow, ensure heater is fully submerged. Unplug and replug after water cools. |
| H1 | High temperature alarm | Water temperature is too high. Check ambient temperature, water flow. |
| H2 | High temperature alarm | Similar to H1, indicates water temperature is above set point. |
| E1 | Low temperature alarm | Water temperature is too low. Check heater wattage suitability for tank size, ensure proper power supply. |
| E2 | Low temperature alarm | Similar to E1, indicates water temperature is below set point. |
| E3 | Water flow/level issue | Indicates lack of water or insufficient water flow. Check filter operation, hose connections, and water level in the tank. |
General Troubleshooting:
- Heater not turning on: Check power connection, ensure outlet is functional.
- Temperature inaccurate: Ensure the sensor area is clean and free from obstructions. Verify water flow.
- Leaks: Check all hose connections for tightness. Ensure O-rings are properly seated.
10. User Tips
- For optimal performance, ensure your external filter provides consistent water flow through the heater.
- Place the heater in a location where it is easily accessible for temperature adjustments and maintenance.
- Monitor your aquarium's temperature with a separate thermometer to cross-reference the heater's display, especially during initial setup.
11. Warranty and Support
This product comes with a manufacturer's warranty. For warranty claims, technical support, or replacement parts, please contact the seller or manufacturer directly. Keep your purchase receipt as proof of purchase.
