HVAC control system and methods for operating same

A method for operating a heating, ventilation, and cooling (HVAC) system having a cooling system and a ventilation system to vent outside air within a structure, the method comprising:

• monitoring an interior temperature of the structure;
• monitoring an exterior temperature and exterior humidity of ambient air outside of the structure;
• associating one or more operating parameters of the HVAC system with a first time range;
• associating one or more operating parameters of the HVAC system with a second time range, wherein the second time range comprises a duration less than the first time range, and the first and second time range combined comprise one day;
• monitoring operational time and operational load of the cooling system for the first time range;
• controlling the ventilation system during the second time range based upon the monitored operational time and operational load of the cooling system in the first time range, the monitored interior and exterior temperatures, the monitored exterior humidity and the one or more operating parameters of the cooling system associated with the second time range;
• executing a first sum of products calculation for operational time and operational load of the cooling system for the first time range;
• executing a second sum of products calculation for operational time and operational load of a heating system for the first time range;
• differencing the second sum of products from the first sum of products;
• and
• controlling the ventilation system for the second time range when the differencing result is a positive value.

A method for operating a ventilation system and a cooling system to vent outside air within a structure, the method comprising:

• monitoring an interior temperature of the structure;
• monitoring an exterior temperature of ambient air outside of the structure;
• defining a first time range and a second time range, wherein the second time range comprises a duration less than the first time range, and wherein the second time range comprises a cooling set point greater than a heating set point associated with the first time range;
• associating one or more operating parameters of the ventilation system and the cooling system with the first time range;
• associating one or more operating parameters of the ventilation system and the cooling system with the second time range;
• monitoring operational time and operational load of the cooling system for the first time range;
• and
• controlling the ventilation system to an ON operating state during the second time range when the monitored operational time and operational load of the cooling system for the first time range is greater than a null value, the monitored interior temperature is greater than the monitored exterior temperature, and the monitored interior temperature is greater than the cooling set point associated with the second time range;
• executing a first sum of products calculation for operational time and operational load of the cooling system for the first time range;
• executing a second sum of products calculation for operational time and operational load of a heating system for the first time range;
• differencing the second sum of products from the first sum of products;
• and
• further controlling the ventilation system to an ON operating state during the second time range when the differencing result is a positive value.