What is the primary purpose of installing an HRV or ERV during a major retrofit according to ASHRAE?

The primary purpose of installing a Heat Recovery Ventilator (HRV) or an Energy Recovery Ventilator (ERV) during a major retrofit is to ensure effective mechanical ventilation. ASHRAE emphasizes the importance of providing adequate ventilation in buildings to enhance indoor air quality and occupant comfort. Mechanical ventilation systems like HRVs and ERVs play a crucial role in achieving this by exchanging stale indoor air with fresh outdoor air while minimizing energy loss.

These systems are designed to recover heat (in the case of HRVs) or both heat and moisture (for ERVs) from the outgoing air, thus improving the overall energy efficiency of the building while maintaining the necessary airflow to meet ventilation standards. This is particularly relevant during retrofits, where existing ventilation may be inadequate, surmounting the need for a more effective solution to improve air quality without significantly increasing energy costs.

Other choices, like increasing energy consumption or focusing solely on air filtration, do not align with the fundamental goals of HRVs and ERVs, which are to balance indoor air quality with energy efficiency. Similarly, while supplemental heating may be a benefit in certain scenarios, it is not the primary function of these ventilation systems.