The development of a "system for analyzing hydraulic faulty connections" is the goal of a research project in which the Technische Hochschule Mittelhessen is collaborating with two medium-sized companies. Project manager at the THM is Dr. Hans-Martin Seipp, Professor of Technical Building Services at the Gießen Department of Life Science Engineering. Partners are Erb Messtechnik from Frankfurt and Schmidt Präzisionstechnik from Schwarza in Thuringia. The Federal Ministry of Economics is funding the project with more than 460,000 euros.
Faulty connections in complex drinking water networks harbor health risks, among other things. In clinics, infectious agents have repeatedly found their way from the cold to the hot water network because the two networks were not strictly separated from each other. Nursing homes, chemical plants or hotels are also prone to faulty installations during the construction phase or during repair work. Limescale deposits and corrosion after a long period of operation can also cause problems.
There are currently two variants for checking faulty connections. With the coloring method, you color the cold water and check whether there are traces of color in the hot water. With the overflow method, the hot water pipe to a building is cut and then it is checked whether hot water is still flowing out, which then overflows from the cold water. Both methods are complex, time-consuming and expensive because the normal operation of the networks has to be interrupted for several hours or days and localizing the fault requires further investigations.
The THM and its partners are developing a completely new solution for detecting faulty connections. A "pulse emission unit" is connected to the network to be tested. It generates pressure pulses in a characteristic time sequence in the cold water network. Pressure probes installed in the cold and hot water network can identify the pressure signal pattern generated by the pulses. If identical patterns appear in both networks at the same time, a faulty connection is proven. With the new method, the test only takes about ten minutes. Further measurements can be used to localize the faulty connection.
Due to the considerable advantages compared to the state of the art, the project partners see good chances of establishing the new method as a standard procedure. It can be used directly when accepting installations, but also for assessments in the event of damage. Even in the case of pipeline networks already in operation with bacterial or chemical contamination, experts can quickly and reliably assess the causes.
The research project will run for two years. It is funded as part of the "Central Innovation Programme for SMEs".