1. Introduction
The EHEIM Jager Aquarium Thermostat Heater is designed to provide precise and reliable temperature control for your aquarium. This 250-watt model is fully submersible and features advanced safety mechanisms to ensure the well-being of your aquatic environment. Please read this manual thoroughly before installation and operation to ensure proper use and longevity of the product.
2. Safety Instructions
- Always unplug the heater from the power outlet before performing any maintenance, cleaning, or handling inside the aquarium.
- Ensure the heater is fully submerged in water before connecting it to a power source. Operating the heater out of water can cause damage and create a fire hazard.
- The heater is equipped with Thermo Safety Control, which automatically turns off the heater if the water level dips too low, preventing dry running.
- This heater is constructed from shock-resistant and shatter-proof glass, suitable for both fresh and marine water aquariums. However, avoid dropping or striking the heater.
- Do not operate the heater if the power cord or plug is damaged.
- Keep out of reach of children.
3. Product Features
- Fully Submersible: Designed for complete immersion in your aquarium.
- Thermo Safety Control: Automatic shut-off mechanism to protect against dry running.
- TruTemp Dial: Allows for recalibration of the heater to achieve precise temperature regulation within +/- 0.5°F.
- Durable Construction: Made of shock-resistant and shatter-proof glass, suitable for both freshwater and saltwater environments.
- On/Off Indicator Light: Provides at-a-glance monitoring of heater operation.
Figure 1: EHEIM Jager Aquarium Thermostat Heater 250-Watt. This image shows the complete heater unit with its power cord and temperature adjustment dial.
4. Setup
- Unpacking: Carefully remove the heater from its packaging. Inspect for any visible damage.
- Placement: Position the heater in your aquarium where there is good water circulation to ensure even heat distribution. While the heater is fully submersible and can be placed horizontally, a vertical or angled placement is generally recommended for optimal performance and temperature sensing.
- Mounting: Use the provided suction cups to securely attach the heater to the inside wall of your aquarium. Ensure it is firmly in place and fully submerged.
- Initial Submersion: Allow the heater to remain submerged in the aquarium water for at least 20-30 minutes before plugging it in. This allows the internal components to acclimate to the water temperature.
5. Operating Instructions
- Set Desired Temperature: Locate the TruTemp dial at the top of the heater. Rotate the dial to set your desired water temperature. The dial typically ranges from 65°F to 93°F (18°C to 34°C).
- Power On: After ensuring the heater has acclimated and is fully submerged, plug the power cord into a suitable electrical outlet.
- Monitor Indicator Light: The heater features an On/Off indicator light. When the heater is actively heating, the light will illuminate. Once the desired temperature is reached, the light will turn off, indicating the heater is maintaining the set temperature.
- Observe Temperature: For the first 24-48 hours, closely monitor the aquarium temperature using a separate, accurate aquarium thermometer to verify the heater is maintaining the desired temperature. Adjust the dial as needed.
6. Calibration
The EHEIM Jager heater features a TruTemp dial for recalibration, allowing you to fine-tune its accuracy. This process ensures the heater's internal thermostat matches the actual water temperature.
- Initial Setup: Install the heater as described in the Setup section and allow it to operate for at least 24 hours to stabilize the aquarium temperature.
- Measure Actual Temperature: Use a reliable, external aquarium thermometer to measure the actual water temperature in your tank. Note this reading.
- Adjust Calibration Ring: If the heater's set temperature (on the dial) does not match the actual temperature measured by your external thermometer, carefully adjust the red calibration ring located just below the temperature setting dial. Rotate this ring until the pointer aligns with the actual temperature measured by your external thermometer.
- Verify: Allow the heater to operate for several hours after adjustment, then re-check the aquarium temperature with your external thermometer. Repeat the calibration process if further fine-tuning is required.
7. Maintenance
- Regular Cleaning: Periodically unplug the heater and gently wipe down the glass tube to remove any algae or mineral deposits. Use a soft cloth or sponge and aquarium-safe cleaning solutions if necessary. Rinse thoroughly before re-submerging.
- Suction Cups: Over time, suction cups may harden and lose their grip. Inspect them regularly and replace them if they show signs of wear or reduced suction. Replacement suction cups are available from Eheim.
- Inspection: Regularly inspect the heater for any signs of damage, such as cracks in the glass or fraying of the power cord. Discontinue use immediately if any damage is observed.
8. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Heater not heating / Aquarium temperature too low. | Not plugged in; power outage; heater not fully submerged; thermostat set too low; heater malfunction. | Check power connection; ensure full submersion; increase temperature setting; recalibrate heater (see Section 6); if still not working, heater may need replacement. |
| Aquarium temperature too high. | Thermostat set too high; heater malfunction; external heat source. | Decrease temperature setting; recalibrate heater (see Section 6); check for external heat sources; if still overheating, unplug immediately and replace heater. |
| Indicator light not illuminating. | Heater not actively heating (temperature reached); power issue; light malfunction. | Verify actual water temperature with external thermometer; check power connection; if heater is heating but light is off, the light may be faulty (heater may still function). |
| Heater turns off unexpectedly. | Thermo Safety Control activated due to low water level. | Check and restore water level in the aquarium. The heater should resume operation once safely submerged. |
9. Specifications
- Model: 3618090
- Wattage: 250 Watts
- Item Weight: 15.2 ounces
- Item Dimensions (LxWxH): 1.95 x 2.5 x 23 inches
- Country of Origin: Germany
- Color: Black
Figure 2: Approximate dimensions of the EHEIM Jager Aquarium Heater. Note that the 250-watt model is approximately 23 inches long.
10. Warranty and Support
For warranty information, technical support, or replacement parts, please contact Eheim customer service directly. Refer to the product packaging or the official Eheim website for the most current contact details and warranty terms applicable to your region.
