Last night I woke at 3 am to an alarm going off and faint blue light emanating from our Maple Chase 9600. It lasted about 10 seconds then shut off (both alarm and light) and the gas furnace immediately kicked on. There was a severe wind storm going on outside, so I'm not sure if the alarm was caused by 1. the power turning back on after being out for some time. 2. A power surge 3. A CO2 alarm 4. Something else. We've experience power outages from time to time in the past, but never an alarm or light from the unit when power was restored. The batteries are relatively new and today the unit is running normally. Nothing in the manual mentions alarms or lights or CO2 warmings. What was this phenomenon?