A fire detection system (100) combines a CO2 gas detector (14) with a smoke detector (2). Logic circuitry (400) combines the outputs of both detectors to minimize false alarms and provide a rapid response time. In a preferred embodiment the need for periodic cleaning is reduced. In a further preferred embodiment, two alarms indicative of two different types of fires, for example flaming fires and nonflaming fires are available. A map (810) of flaming fire and smoke may be assembled by the system to guide the firefighters. In a yet another preferred embodiment, a tentative fire alarm indication (222, 233) disables a local air conditioning system thereby helping to isolate and control any existing fire. 00000