Patent ID: 9662519
Date: 2017-05-30
CPC Classifications: A62C,F24C

Claim:
1. A method of detecting a condition in an exhaust ventilation system including an exhaust hood, the method comprising: receiving, at a control module, an exhaust air temperature signal representing a temperature of the exhaust air in a vicinity of the exhaust hood, the exhaust air temperature signal being generated by a temperature sensor; receiving, at the control module, a radiant temperature signal representing a temperature of a surface of a cooking appliance that generates the exhaust air, the radiant temperature signal being generated by a radiant temperature sensor; receiving, at the control module, a pressure signal representing the pressure in the hood; regulating a flow of exhaust to a first flow rate associated with an idle status of the cooking appliance responsively to the received exhaust air temperature signal, the received radiant temperature signal, and the received pressure signal; and regulating a flow of exhaust to a second flow rate, higher than the first flow rate, associated with a high load cooking status of the cooking appliance responsively to the received exhaust air temperature signal, the received radiant temperature signal, and the received pressure signal; and regulating a fire suppression mechanism responsively to at least one of the received exhaust air temperature signal, the received radiant temperature signal, and the received pressure signal, using said control module, and responsively to said radiant temperature, exhaust temperature, and a further signal, distinguishing a flare-up from a grill from a fire and regulating a flow rate of the exhaust and/or regulating a fire suppression mechanism responsively to the distinguishing, wherein the fire suppression mechanism is activated in response to a calculation by said control module of a total heat gain above a predetermined magnitude threshold combined with a duration of the heat gain being above a predetermined duration threshold.