Dynamic Modelling and Simulation of Faults in a R290-Based Air-to-Water Heat Pump System

Domestic air-to-water heat pumps are becoming increasingly popular due to their high efficiency and environmental benefits. However, their reliability and performance can be affected by a variety of faults, which can result in significant energy losses and maintenance costs. Experimental evaluation of failure effects is often time-consuming and costly, requiring extensive laboratory testing. This paper presents a novel approach to model and simulate the effects of faults in an R290-based domestic air-to-water heat pump using a MATLAB Simscape acausal dynamic simulation model. The developed model accurately captures the dynamic behaviour of the heat pump system and allows the evaluation of various fault scenarios, including heat exchanger fouling, refrigerant leaks, compressor failures, and sensor malfunctions. The simulation results show mainly the impact of evaporator fouling and a little of condenser one on system performance, energy efficiency, and safety. The proposed model enables the identification of critical fault modes and the evaluation of fault detection and diagnosis strategies, reducing the need for costly and time-consuming laboratory experiments. The study also investigates the effects of fault severity and duration on system performance and energy efficiency. The results of this study can be used to improve the design, operation, and maintenance of domestic air-to-water heat pumps, ultimately increasing their reliability and performance. The model developed can also be extended to other types of heat pumps and HVAC systems, making it a valuable tool for researchers and practitioners in the field.