Originally Posted by doublewing11
10" make-up damper attached to return hub which is also wired to all exhaust fans/vents
That's what my builder originally suggested, but it isn't perfect either. It doesn't solve the humidity problem in an otherwise cool basement. Pulling fresh air directly from outside would be worse in terms of injecting humidity into conditioned space vs using an ERV. It's also 0% efficient (no humidity or energy exchange between outgoing & incoming air).
It would be best to remote mount the exhaust blower. You need something to control when the exhaust vents turn on/off (temperature, timer, program, manual switch, etc). Then you also need the additional wiring & control to activate the main AC blower & open the make up air damper. Running the blower without cooling can create humidity problems on its own, without even factoring in outside air.
An ERV packages all that, and adds some degree of efficiency. The efficiency helps with the humidity problem, but not 100%. It also avoids circulating air over the wet HVAC coils from the prior cooling cycle (adding humidity back into the air). My main complaint with the Broan ERV is the lack of intelligence for turning exhaust on/off, and their lack of support for any 3rd part intelligent controllers. They're not necessarily a bad solution, but could be better. Not saying the 10" make up air duct is bad either, just that it has its own problems as well.
Another forum member was considering bringing fresh air in through a dehumidifier. The Ultra-Aire XT105H has a fresh air intake and a built in exterior damper. He would still need to exhaust the theater air outside to make room for the fresh air. It would solve the humidity problem, but is also 0% efficient. Ideal would be to combine products in a way so the ERV handled ventilation, then passed the fresh air to AC, then to de/humidifcation, and finally onto distribution. But that's complicated and not something I would want to try to cobble together.Edited by rabident - 12/18/13 at 11:04am