Introduction
The Melnor 15339 Hydrologic Soil Moisture Sensor is designed to monitor soil moisture levels and communicate with compatible Melnor Hydrologic timers. This functionality allows the timer to automatically delay watering cycles when sufficient moisture is detected, preventing overwatering and conserving water resources. This sensor is intended for outdoor use only.
Safety Information
Warning:
This product may expose you to chemicals, including styrene, which is known to the State of California to cause cancer. For more information, please visit www.P65Warnings.ca.gov. This device is for outdoor use only.
Product Overview
The Melnor 15339 Hydrologic Soil Moisture Sensor consists of a sensor probe designed for insertion into the soil, a control unit with an adjustable dial, and a wired connection to link with a compatible Melnor Hydrologic timer.
Figure 1: Front view of the Melnor 15339 Hydrologic Soil Moisture Sensor, showing the control unit with a yellow dial and the soil probe, connected by a black cable.
Figure 2: Back view of the Melnor 15339 Hydrologic Soil Moisture Sensor, displaying the "DRYER" to "WETTER" sensitivity settings and the "SENSOR NOT OPERATIONAL" indicator.
Setup
- Placement: Select an area in your garden or lawn that accurately represents the moisture conditions of the plants you wish to water. Avoid placing the sensor directly under sprinklers or in areas that receive excessive runoff, as this can lead to inaccurate readings. Ensure the sensor is placed away from any direct watering sources to prevent false readings.
- Insertion: Gently push the sensor probe into the soil to the desired depth. The depth should correspond to the root zone of the plants being monitored. Ensure the sensor is firmly in place to maintain good contact with the soil.
- Connection: Connect the sensor's cable to the designated port on your compatible Melnor Hydrologic timer. Refer to your timer's instruction manual for the exact location of the sensor input port.
- Cable Management: Route the sensor cable to prevent tripping hazards and protect it from damage by garden tools or animals. The cable is designed to be long enough for flexible placement.
Figure 3: The Melnor soil moisture sensor correctly installed in garden soil, blending with the landscape.
Operating Instructions
The Melnor 15339 sensor works in conjunction with a compatible Melnor Hydrologic timer to optimize watering schedules based on actual soil moisture levels.
- Initial Power-Up: Once connected to the timer, the sensor will begin to read soil moisture. The timer's display should indicate that the sensor is recognized and operational.
- Adjusting Sensitivity: The sensor features an adjustable dial to set the desired moisture threshold.
- Rotate the dial towards "DRYER" (fewer water droplets) to allow watering to occur when the soil is relatively dry.
- Rotate the dial towards "WETTER" (more water droplets) to delay watering until the soil is significantly drier.
- Automatic Watering Delay: When the soil moisture level at the sensor's location exceeds the set threshold, the sensor will signal the connected Melnor Hydrologic timer to temporarily suspend or delay scheduled watering cycles. Watering will resume automatically once the soil moisture drops below the set threshold.
Figure 4: A hand adjusting the yellow dial on the Melnor soil moisture sensor to set the desired moisture sensitivity.
Maintenance
- Regular Cleaning: Periodically inspect the sensor probe for dirt, debris, or mineral buildup. Gently clean the probe with a soft cloth and water to ensure accurate readings.
- Cable Inspection: Check the sensor cable for any signs of damage, such as cuts, fraying, or exposed wires. Damaged cables can affect sensor performance.
- Winter Storage: Before the first frost, disconnect the sensor from the timer and remove it from the soil. Clean the sensor thoroughly and store it in a dry, protected area where temperatures remain above freezing.
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Sensor not delaying watering / Timer waters even when soil is wet. |
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| Sensor always delays watering / Timer never waters. |
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| Timer does not recognize sensor. |
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Specifications
- Model Number: 15339
- Brand: Melnor
- Color: Black
- Product Dimensions (L x W x H): Approximately 15.5 cm x 5.6 cm x 4.2 cm (6.1 in x 2.2 in x 1.65 in)
- Item Weight: Approximately 109.77 g (0.24 lbs)
- Battery Requirement: No batteries required (powered by compatible timer)
- Mounting Type: Freestanding (soil insertion)
- Operating Temperature Range: Up to 40°C (104°F)
- Included Components: 1x Soil Moisture Sensor
- Manufacture Location: Taiwan
Warranty
The Melnor 15339 Hydrologic Soil Moisture Sensor comes with a 7-Year Manufacturer Limited Warranty. Please retain your proof of purchase for warranty claims. For detailed warranty terms and conditions, refer to the official Melnor website or contact customer support.
Customer Support
For further assistance, technical support, or to inquire about compatible Melnor Hydrologic timers, please visit the official Melnor website or contact their customer service department. Manufacturer contact information: Winchester, VA 22603, USA.