During a recent thunder storm, the security/fire system made a terrible noise.  I tried to shut it off at the keypad, but the sound persisted.  I went upstairs to shut it down at the control panel.  When I went through the bathroom on my way to the closet where the control panel was located, I saw a fire in my toilet!  My house was on fire!  My system had already sent out a fire alarm . The fire department arrived, extinguishing the blaze and saved my home.  We later determined that lighting had struck an upstairs bathroom vent igniting it.  The fire then burned through the roof and ceiling and had fallen into the toilet.  Thanks to the fire system, the fire department arrived before the fire caused extensive damage and was able to spread.  I shudder to think what could have happened if I had ignored the warning signals of my system.