The residential sector accounts for 27% of the EU's total energy consumption, and more than half is used for space conditioning, so improvements in this sector would contribute to achieving the sustainability goals set. Heat pumps (HP) have been presented as a good solution, as they are systems capable of satisfying air-conditioning needs in a more efficient way than systems based on fossil fuels; moreover, the REPowerEU Communication established the objective of doubling the current HP deployment rate in the next years. In this sense, designing and optimizing air conditioning systems is crucial. This study presents a method to determine the power and airflow parameters of a fan in a heat pump air conditioning system. The calculation is performed considering the pressure drop associated with the design of the heat exchangers using the IMST-ART simulation tool. This modeling aims to obtain simulations closer to the real behavior under different design conditions for the development of more efficient air conditioning systems