The use of photovoltaic electricity to drive heat pumps in combination with latent thermal energy storage (LTES) is a promising solution for sustainable HVAC. The present study aims to understand the optimal sizing for the components of a sustainable residential HVAC system by considering the total cost of investment and operation. The HVAC system of a detached house in Venice, Italy, is evaluated. The system consists of a heat pump, an LTES and a photovoltaic array. The heat pump can be driven by both the photovoltaic array and the electric grid. The dynamic behavior of the system is evaluated via a numerical model with a rule-based control that aims to maximize the utilization of renewable energy. From model results, the total energy consumption and the fraction of photovoltaic electricity that is self-consumed are determined for each year of operation. The results for the energy flows are incorporated in an economic analysis to estimate the total cost for HVAC during a 20-year lifetime as function of the LTES and heat pump nominal capacity. PV self-sufficiency and self-consumption are found to rapidly increase with LTES capacity up to a value of around 25 kWh. At current commercial prices for LTES of around 200 €/kWh, there is not an economic advantage of including the storage, and the minimum total cost is achieved with zero LTES capacity.