I have a bryant (apparently made by generac) 15,000W, had in place since I built in 2007. On the control panel on the unit, beside the buss fuses is a small GFCI plunger-type breaker. It has popped up. I cannot find a reset anywhere to get the unit back online. I'm waiting on my dealer but probably another week out while he fixes people who had no heat during this cold blast. Up until this week, it was working fine, did the self check each week, etc. The battery is charged and both the 7.5 and 15 amp fuses are good. Any ideas?

What happens when you push in the "plunger" on the GFCI