Abstract: A ventilation arrangement for a commode that is refilled after flushing with a water supply valving includes a tank with the water containing portion, a drain pipe for communicating between the tank and a bowl and an air transmission conduit that includes a blower and a blower ventilation duct that extends from the drain pipe to the blower for pulling a suction on openings within the base of the commode. An air flow control arrangement includes a housing that provides resistance to water flow into the air ventilation duct during a flush even while the blower is ventilating. During a flush, air flow seeks a path of least resistance through the housing. After flushing occurs, air flow seeks a path of least resistance through the closed tank drain line to the openings in the bowl.