We have a multi unit high rise residential bldg. and we are attempting to provide natural ventilation to all units using the operable windows and sliding doors. We have confirmed the amount of opening area complies with ASHRAE 62.1. The sticky part is that the units are greater than 25 feet in depth from with openings. In reviewing the comments it appears acceptable to use a fan/blower to assist in the movement of the air deeper into the interior of the units and to have a manual switch that the user can operate as needed.
Assuming the above premise is correct, could we not use the central a/c unit air handler to serve the same function. The unit thermostat has an off/on/auto function for the fan that allows the user to operate as needed. The fan (whose intake is located in the first 25 feet) would recirculate the air to distribute the fresh air to areas that are more than 25 feet away from the openings serving the same function as a booster fan. This seems like a more sustainable solution than installing a new system that would accomplish the same function.
A second solution would be to use the same system but install a CO2 sensor in the area more than 25" away and have it control the fan as needed but this would seem like overkill. Thoughts?