Development Of Trnsys Model For Energy Performance Simulation Of Variable Refrigerant Flow Air-Conditioning System Combined With Energy Recovery Ventilation

The variable refrigerant flow air-conditioning system is an HVAC system that can perform at a high capacity with low consumption thanks to its variable-speed compressor. The paper introduces a TRNSYS model to build a simulation model to calculate the energy performance of an existing variable refrigerant flow system and to build a model that can be used as a reference when a VRF system is proposed to a certain situation. The TRNSYS model was compared with the actual energy consumption to see the data agreement between the two models. Temperature, Relative Humidity, and energy consumption were metered using proper instruments, and it was compared with the obtained simulation results. The validation of the simulation model showed close values to the actual system, as the obtained Normalized Mean Bias Error (NMBE) between the simulation and measured values for temperature and relative humidity was 4.3 and 7.6%, respectively. While it was around 7.8% for the total energy consumption. Besides, the paper proposed an Energy Recovery Ventilation to be simulated with the existing TRNSYS model to compare it with the same system without ventilation to see if it is feasible to add an Energy Recovery Ventilation unit to the existing system. It shows a worthy reason to be used, as it saves 18.8% annually of the energy consumption of the system.