Intelligent Bypass Damper Operation in an HVAC System With Zones

A system controller of an HVAC system comprising:

• a processor;
• and
• a memory comprising program instructions that when executed by the processor cause the processor to:
• determine a relative size of a virtual zone that is associated with a bypass damper of the HVAC system, wherein the relative size of the virtual zone is representative of a share of a total system airflow that is delivered to the virtual zone when the bypass damper is in a fully open position;
• generate corrected positions for intermediate damper positions of the bypass damper between the fully open position and a fully closed position to obtain a linear behavior of airflow through the bypass damper;
• when the airflow of conditioned air to at least one zone of the HVAC system exceeds a maximum airflow value for the at least one zone,
• adjust a damper position of the bypass damper to one of a plurality of corrected positions to bypass a portion of the conditioned air to the virtual zone,
• wherein the portion of the conditioned air that is bypassed is a minimum amount of the conditioned air that is needed to reduce the airflow of the conditioned air to the at least one zone below the maximum airflow value and keep the HVAC system running,
• wherein the one of the plurality of corrected damper positions is selected based on the minimum amount of the conditioned air that is to be bypassed to the virtual zone and the relative size of the virtual zone;
• and
• close the bypass damper when a temperature of the portion of the conditioned air that is bypassed exceeds a first threshold temperature.