Our carbon monoxide detector went off today. After much checking by the fire department the problem was traced to a leaking regulator on my CO2 tank. (It was on while carbonating a keg.) The regulator was leaking out the front, almost certainly due to a failed diaphragm. One of the fire fighters used to install soda systems, so he knew CO2 would set off the alarm, and recommended where to check the regulator. I didn’t have a soap solution premade, but a Star San spray bottle worked quite well as a leak detector. Once I took the tank outside the monitor he had dropped quickly.
The firemen were professional, friendly, and extremely curious about the brewery. I have a red rye fermenting right now. It’s a new recipe, but if it turns out OK I think I’ll take a case down to the station to say thanks.