Never disregard a carbon monoxide alarm! On July 23, 2015 at 2137 hours Engine 160, Rescue 26 and Car 2552 responded to an address on Lake Drive for a carbon monoxide detector activation. Upon arrival all residents were evacuated and elevated levels of CO were observed by crews operating in the residence. The source was determined to be a displaced flue on a water heater. The unit was taken out of service and the residence ventilated. Levels were re-checked and the homeowner was advised to have the unit repaired by a professional. Thankfully this homeowner contacted us rather than try to reset the alarm.