DON'T cut a hole in your header !!!

Forget using the whole house fan as part of the solution.

ERV - energy recovery ventilators come is all shapes, sizes and flavors. They can stand alone or tie into your HVAC system.

Panasonic makes a simple make up air solution but it doesn't temper the air coming into the house like an ERV does.

Here is a link that might be useful: Panasonic make up air

In cold climates, the MUA should be heated for comfort except in naturally hot commercial kitchens. 1100 cfm will replace the air in its path in most houses in several minutes, and room heating systems are not normally sized to be sufficient to reheat the room air at the rate that the MUA supplies it.

Big commercial systems often use electrical heaters, propane heaters, or natural gas heaters within the filter/fan assembly (see Greenheck.com for examples). I have a heat exchanger (radiator) supplied by my hot-water heating furnace that should be able to transfer more than a 100000 BTU/hr to the incoming air. The MUA path (when I complete it) will flow through this radiator. It also has to flow through an air filter (like a hot-air furnace filter). The pressure losses at high flow rate through the radiator, air filter, diffuser, ducting, and roof-top screened air intake are sufficient for me to want to include a large Flowtek fan (not yet acquired) to keep the house pressure at a recommended modest negative value.

The complication is that the cook-top vent hood fan is variable, the wall oven overhead vent fan is variable, there are three bathroom fans that can be on or off, possible fireplace operation, dryer, and furnace. Balancing the pressure will require a motor controller controlled by the differential house pressure.

(Note: Large building HVAC may perform this function by keeping their motors running at a constant speed and varying how much outside air is bypassed between motor output and intake.)

kas