The installations described here concern new systems that may include wall-mounted heat pumps , wall-mounted air conditioners , central heat pumps , central air conditioners , multi-zone systems , air-to-water systems , PTAC/VTAC , as well as ventilation ( air exchangers , humidity control , fresh air supply ), depending on the building configuration and operational objectives. These solutions are applicable to houses , multi-unit residential buildings , commercial spaces , and mixed-use buildings , with a selection process based on: • building characteristics (envelope, volumes, layout, ductwork options) • usage profiles (occupancy, schedules, priority zones, fresh air requirements) • thermal loads and operational objectives (performance, stability, energy efficiency) in order to align sizing and architecture.