Duct Design Issues: Innovative Preheating of Outside Air

Recently, I reviewed the HVAC system for the dining room at the McGraw House. This seven-story senior citizen housing building in Ithaca, N.Y. was constructed in 1972. The owner was dissatisfied with the ventilation of the facility's kitchen. The 1972 drawings indicated that return air was taken from the dining room and part of it was introduced into the kitchen to supply makeup air to the kitchen range exhaust hood. Additional air was directly introduced to the kitchen through the doors between the kitchen and the dining room.