A method for determining a set of optimized control parameters (θ k) of a closed-loop controller or an open-loop controller for a HVACR (heating, ventilation, air conditioning and refrigeration) system, comprising the following steps: detecting an outside temperature ( T A); detecting an actual room temperature ( T R) of a room; detecting a supply temperature (T VL); detecting a preset target room temperature ( T R,W); detecting a preset target supply temperature ( T VL, W); generating a data packet ( D k) with said detected measurement values ( T A, T R, T R,W, T VL, T VL,W) and a time ( t k) of detection; transmitting said data packet ( D k) to a server via an internet connection; storing said data packet ( D k) in a storage medium (6, 7) connected to said server; characterized by: calculating a set of optimized control parameters (Θ k) based on the measurement values ( T A, T R, T R,W, T VL, T VL,W) of the transmitted and stored data packet ( D k) and based on: measurement values ( T A, T R, T R,W, T VL, T VL,W) of a plurality of further data packets ( D 0... k) generated at earlier times ( t 0... k) of a specific period (Δ t); and/or at least one of a plurality of previously determined sets of optimized control parameters (Θ k -1); wherein the set of optimized control parameters (Θ k) is calculated by executing a calculation algorithm on said server; storing the calculated set of optimized control parameters (Θ k) in said storage medium (6, 7) connected to said server; and transmitting the calculated set of optimized control parameters (Θ k) from said server to the closed-loop controller or the open-loop controller of said HVACR system via the internet connection or sending a notification to a user of said HVACR system with the calculated set of optimized control parameters (Θ k). detecting an outside temperature ( T A); detecting an actual room temperature ( T R) of a room; detecting a supply temperature (T VL); detecting a preset target room temperature ( T R,W); detecting a preset target supply temperature ( T VL, W); generating a data packet ( D k) with said detected measurement values ( T A, T R, T R,W, T VL, T VL,W) and a time ( t k) of detection; transmitting said data packet ( D k) to a server via an internet connection; storing said data packet ( D k) in a storage medium (6, 7) connected to said server; characterized by: calculating a set of optimized control parameters (Θ k) based on the measurement values ( T A, T R, T R,W, T VL, T VL,W) of the transmitted and stored data packet ( D k) and based on: measurement values ( T A, T R, T R,W, T VL, T VL,W) of a plurality of further data packets ( D 0... k) generated at earlier times ( t 0... k) of a specific period (Δ t); and/or at least one of a plurality of previously determined sets of optimized control parameters (Θ k -1); wherein the set of optimized control parameters (Θ k) is calculated by executing a calculation algorithm on said server; storing the calculated set of optimized control parameters (Θ k) in said storage medium (6, 7) connected to said server; and transmitting the calculated set of optimized control parameters (Θ k) from said server to the closed-loop controller or the open-loop controller of said HVACR system via the internet connection or sending a notification to a user of said HVACR system with the calculated set of optimized control parameters (Θ k). calculating a set of optimized control parameters (Θ k) based on the measurement values ( T A, T R, T R,W, T VL, T VL,W) of the transmitted and stored data packet ( D k) and based on: measurement values ( T A, T R, T R,W, T VL, T VL,W) of a plurality of further data packets ( D 0... k) generated at earlier times ( t 0... k) of a specific period (Δ t); and/or at least one of a plurality of previously determined sets of optimized control parameters (Θ k -1); measurement values ( T A, T R, T R,W, T VL, T VL,W) of a plurality of further data packets ( D 0... k) generated at earlier times ( t 0... k) of a specific period (Δ t); and/or at least one of a plurality of previously determined sets of optimized control parameters (Θ k -1); wherein the set of optimized control parameters (Θ k) is calculated by executing a calculation algorithm on said server; storing the calculated set of optimized control parameters (Θ k) in said storage medium (6, 7) connected to said server; and transmitting the calculated set of optimized control parameters (Θ k) from said server to the closed-loop controller or the open-loop controller of said HVACR system via the internet connection or sending a notification to a user of said HVACR system with the calculated set of optimized control parameters (Θ k).