Patent ID: 8702482
Filing Date: 2014-04-22
Classification: F24F,Y02B

Abstract:
1. An HVAC system for a building that defines an outdoor area and an indoor area, the building includes a specified number of rooms and a specified amount of floor space, the HVAC system comprising: a main blower configured to deliver temperature-conditioned air into the indoor area through a first supply path that extends from the main blower to the indoor area and joins the main blower and the indoor area in fluid communication; a ventilation blower configured to deliver ventilation air from the outdoor area and into the indoor area through a second supply path that extends from the ventilation blower to the indoor area and joins the ventilation blower and the indoor area in fluid communication; wherein the second supply path is independent from the first supply path; and a controller comprising a drive unit for providing power to a motor, the controller operatively coupled to the ventilation blower to render the ventilation blower selectively operable in a normal mode and an alternate mode, such that: the controller determines the actual ventilation flow rate through the ventilation blower as a function of the rotational speed of the ventilation blower and the power consumption of the motor of the ventilation blower; a control system having an electrical output for providing appropriate electrical power to a motor of the ventilation blower and a manual input, wherein the electrical output is operatively coupled to the ventilation blower for urging the ventilation blower to move the ventilation air at a target ventilation flow rate through the ventilation blower, wherein the target ventilation flow rate is based on a setup signal that is communicated to the controller via the manual input, wherein the setup signal is based on the specified number of rooms and the specified amount of floor space; wherein the control system is configured to determine the actual ventilation flow rate through the ventilation blower as a function of the rotational speed of the ventilation blower and the power consumption of the motor; wherein the control system is configured to selectively regulate a rotational speed of the ventilation blower over a range of rotational speed values, the range including a rotational speed value of zero and a plurality of positive rotational speed values, in response to a change in the determined actual flow rate; and wherein the HVAC system is free of a fluid duct configured to allow delivery of return air to the indoor area through the second supply path.