Capacity control for HVAC system

A method of controlling a heating, ventilation, and air conditioning (HVAC) system that includes HVAC equipment configured to provide conditioned air to a conditioned space that is divided into zones, the method comprising:

• receiving zone priority levels and zone temperature setpoints, at least one of the zones having a higher priority level than others of the zones;
• receiving an indication of zone ambient temperature values;
• determining requested zone capacity values to maintain the zone ambient temperature values within a threshold deviation of respective ones of the zone temperature setpoints;
• determining target zone capacity values from the requested zone capacity values and zone size values, and from the zone priority levels responsive to a total of the requested zone capacity values that is less than a minimum capacity of the HVAC system or greater than a maximum capacity of the HVAC system
• the target zone capacity values are determined to correspond to the requested zone capacity values scaled by respective ones of the zone size values, responsive to the total of the requested zone capacity values between the minimum capacity and the maximum capacity;
• and
• causing the HVAC system to provide the conditioned air to the zones according to respective ones of the target zone capacity values, wherein
• the HVAC equipment is set up in an installation with zone dampers controllable to regulate airflow of the conditioned air to respective ones of the zones;
• converting the target zone capacity values to target zone airflow values for the zones of the conditioned space;
• determining a damper position set from the target zone airflow values;
• and
• actuating the zone dampers to respective damper positions of the damper position set.

A non-transitory computer-readable storage medium, comprising program instructions, which, when executed by one or more processors of a computing system, perform a method of controlling a heating, ventilation, and air conditioning (HVAC) system that includes HVAC equipment configured to provide conditioned air to a conditioned space that is divided into zones, the method comprising:

• receiving zone priority levels and zone temperature setpoints, at least one of the zones having a higher priority level than others of the zones;
• receiving an indication of zone ambient temperature values;
• determining requested zone capacity values to maintain the zone ambient temperature values within a threshold deviation of respective ones of the zone temperature setpoints;
• determining target zone capacity values from the requested zone capacity values and zone size values, and from the zone priority levels responsive to a total of the requested zone capacity values that is less than a minimum capacity of the HVAC system or greater than a maximum capacity of the HVAC system
• the target zone capacity values are determined to correspond to the requested zone capacity values scaled by respective ones of the zone size values, responsive to the total of the requested zone capacity values between the minimum capacity and the maximum capacity;
• and
• causing the HVAC system to provide the conditioned air to the zones according to respective ones of the target zone capacity values, wherein
• the HVAC equipment is set up in an installation with zone dampers controllable to regulate airflow of the conditioned air to respective ones of the zones;
• converting the target zone capacity values to target zone airflow values for the zones of the conditioned space;
• determining a damper position set from the target zone airflow values;
• and
• actuating the zone dampers to respective damper positions of the damper position set.