Project requirements: Cost-effective, scalable and robust monitoring of district heating shafts
The aim of the project is to monitor the fill level and temperature in district heating shafts, which are often located under roads or traffic areas, in a cost-effective and reliable manner. The solution must be price-sensitive in order to enable broad scaling across many measuring points in an economical manner. At the same time, industrial quality is required to ensure long-term use in harsh environmental conditions such as humidity, dirt and temperature fluctuations.
The project must ensure that reliable and long-term stable recording and transmission of measurement data is guaranteed even under difficult structural conditions. The requirements include low-maintenance operation, high flexibility in integration into existing systems, and suitability for use in deep shafts with limited installation options. In addition, the project must ensure easy retrofitting and consistently high measurement and transmission quality.
Partner solution: Intelligent level and temperature monitoring with energy-efficient wireless connection
The solution is based on a combination of a WIKA level switch with integrated temperature measurement and the external LoRaWAN® and mioty radio unit NETRIS®1. The level switch detects defined switching points for level detection and simultaneously measures the medium temperature when liquid is detected. This means that in the event of water ingress into the shaft, it is possible to detect whether it is cold rainwater or warm water from the district heating system. Thanks to real-time data transmission and differentiated status evaluation, the correct measures can then be taken.
Individually selectable cable lengths between the sensor and radio unit allow the solution to be flexibly adapted to different shaft and installation situations, enabling the NETRIS®1 to be placed in the optimal position for radio reception.
The NETRIS®1 is installed outside the shaft, ensuring a stable radio connection. The wireless transmission of measurement and switching information is carried out in an energy-efficient manner via LoRaWAN®. Smart limit value detection with event-based data transmission reduces unnecessary data transfers during normal operation and enables a very long battery life, even with continuous use.
Effects and benefits of WIKA's IoT partner solution
Continuous level and temperature monitoring reduces the considerable operational effort involved in manual shaft inspections, which are often necessary under roads or traffic areas. Such operations involve travel, traffic safety measures, opening the shaft and the deployment of at least two employees. Permanent remote monitoring eliminates these routine operations.
The integrated temperature measurement also enables a clear distinction to be made between penetrating rainwater and warm district heating water. This prevents false alarms and ensures that actual leaks are detected early and reported in a targeted manner. Operations are carried out exclusively on an event- and needs-oriented basis. This reduces vehicle costs, minimises traffic disruption, increases occupational safety and enables seamless, automatic documentation without additional manual effort.
Philipp Lausberger, IIoT Application Specialist
The aim is to monitor the fill level and temperature in district heating shafts, even under roads or traffic areas, in a cost-efficient and reliable manner. The combination of intelligent level switches and energy-efficient LoRaWAN radio technology from WIKA makes it possible to detect water ingress, distinguish between cold rainwater and warm district heating water, and take the appropriate measures. The solution is flexible, low-maintenance and allows for easy retrofitting of existing systems. This reduces routine operations, increases work safety and avoids traffic disruptions.
