Return temperature limiter
A return temperature limiter (short: RTL for return temperature limiter or RTL valve ) is a special thermostatic valve that is used in heating or cooling circuits. There it measures the temperature of the heat transfer medium . In the case of heating, it reduces the flow rate of the medium when the temperature is above a threshold value so that it stays longer in the upstream heat exchanger (radiator, floor) and gives off more heat. This serves to increase the efficiency of the system. The best known use is in underfloor heating .
functionality
A return temperature limiter is located in the return of a heating or cooling circuit. It consists of a temperature sensor and a valve , usually in the form of a thermostatic valve. It measures the temperature of the heat transfer medium in the return and regulates its flow rate via its valve. The aim is to ensure a sufficiently high temperature difference between the flow and return over the length of time in the output heat exchanger (e.g. radiators or cooling surfaces) in order to keep the heat exchanger in the generator (e.g. boiler) in an optimal operating window. This increases the efficiency of the system and also protects heating systems from overheating.
Return temperature limiters are mainly used for surface heating . They can also be found in cooling systems, water heaters, boilers, district heating systems and in some industrial systems.
Individual evidence
- ↑ a b How does a return temperature limiter work? In: energie-experten.org . Retrieved March 2, 2019 .
- ^ Hermann Rietschel, Wilhelm Raiss: Heiz- und Klimatechnik . Springer Verlag, 2013, ISBN 978-3-662-38191-5 , pp. 144 ( limited preview in Google Book search).
- ^ Herbert Wiemann, Ulrich Eberle, Alfred Soherr: Metallfachkunde 5: Heating and ventilation technology . Springer Verlag, 2013, ISBN 978-3-322-96780-0 , pp. 309 ( limited preview in Google Book search).