12 volt system "cycles" when heater is running

Plugged into shore power. Discovered something interesting however, on the power pedestal the 110 side that powers our outside pipe wrap and some patio lights the CFI keeps popping off - I wonder if that in someway causes a surge (although I have a surge protector at the pedestal) and that somehow interferes with the 12 volts last night? Like I said today, there's no issue.