The main objective of the project is to develop modular airflow diffusers that will be used to optimise the noise enclosures of air-to-water heat pumps. The output of the project will be a working sample (optimised enclosure) and a utility model (modular airflow diffuser of the noise protection enclosure). Based on experimental testing of the functional sample, an acoustic-energy overview catalogue will be compiled mapping the correlation between acoustic and energy parameters of the heat pump before and after being enclosed in the enclosure. The 1D acoustic-energetic mathematical model of the heat pump, which will be developed in the framework of this project, will be used to create the catalogue.