I’m building a super insulated, very tight home.  I have infloor heat using a sealed high efficiency condensing hot water heater.  I am installing a HRV capable of venting a 1200 sq foot house.  I am placing the fresh air into the bedrooms and the living room and the exhaust vents in the kitchen (above the sink/dishwasher) and in the bath/laundryroom.  I will ballance the system and have a booster control for the bathroom.  My question is if everything is installed properly and I turn on the exhaust fan above the stove and run the dryer, where does the makup air come from?  I havn’t been able to find ANY information regarding proper HRV system design and how it is affected by kitchen/bath/dryer vents.  Seems to me that if the HRV is ballanced and you turn on the dryer it will simply pull more air in through the HRV inlet reducing it’s efficiency only for the time in which the fan is running.  Would it also create a negative pressure in the house?  Any thoughts from experienced HVAC guys out there?  Much appreciated!