My water heater has an external exhaust fan which normally turns on
while the water heater is operating. Recently after I had to shut off
the water heater to replace a leaky outlet hose, the exhaust fan
started operating constantly, whether or not the water heater is
operating. An old instruction sheet said to push the two reset
buttons in the center of the draft spillage switches, but they don't
seem to do anything. Any advice?