Patent ID: 8052062

Claim:
A constant air volume heating and cooling control system in a multiple zoned building comprising: each zone having an output for supplying conditioned air to said zone and an input for receiving return air from said zone; a constant volume central air handling unit for delivering air at a controlled dew point temperature to ensure desirable zone humidity through a constant air volume supply air duct to all of said zones; a return air duct for delivering return air from all of said zones to said central air handling unit; a heat exchanger for each zone for exchanging heat between air from said central air handling unit to said output and a variable amount of return air from each input to said return air duct; an air flow bypass for excess return air from the inlet of each zone to said return duct; and, a zone modulating fan downstream of each said heat exchanger having an exhaust duct leading to said return duct for regulating airflow through said heat exchanger for each zone to produce said variable amount of return air and maintaining said constant volume of air.