In Reply to: Re: Update posted by SelectOSpeed on January 19, 2018 at 09:51:17:
I failed to mention that Low Oxygen Content in Room Air will cause the burner to emit CO also. That is why Modern Unvented Gas appliances are equipped with a Oxygen Depletion Sensor in the Pilot assembly. This device is designed to extinguish the Pilot flame to effect a Safety Shutdown of the appliance before room Oxygen drops to a Unsafe level. SoS.