What role do inlet and exhaust fans play in an HRV?

In the context of a Heat Recovery Ventilator (HRV), inlet and exhaust fans are essential components that facilitate air exchange between the inside and outside of a building. Their primary function is to enable the transfer of stale indoor air to the exterior while simultaneously bringing in fresh outdoor air. This process is crucial for maintaining indoor air quality and ensuring proper ventilation.

The inlet fan draws in fresh air from outside, which is then passed through the HRV's heat exchange core. Simultaneously, the exhaust fan expels the stale indoor air. The unique design of the HRV allows for the heat from the outgoing air to transfer to the incoming air, thereby improving energy efficiency by reducing the heating or cooling load on HVAC systems.

While there are other roles that HVAC components can serve, such as air filtration and circulation, the primary purpose of the fans in an HRV is to facilitate effective air exchange, ensuring a balance of fresh air intake and indoor air expulsion. This is why the correct answer highlights their crucial role in promoting air exchange within the system.