I have a GFCI outlet in the garage next to the main breaker box. The
only thing that plugs into this outlet is the automated sprinkler
system. I have had the house for about five years (new when bought). I
remember the GFCI outlet occasionally tripped (not often prior to this
year). Now, I noticed the outlet tripped frequently, typically during a
sprinkler session. In fact, this is getting worse lately. When I found
it tripped, I would reset it, and the sprinkler would continue where it
was interrupted. The sprinkler has six zones, and almost always, thus
far, it was shut off during zone 5 because the GFCI outlet tripped.
Then, barely a few minutes later, the outlet was tripped again. Now, I
cannot even reset the outlet - the reset button keeps popping out, even
with the sprinkler unplugged. If I waited a few hours, then I can reset
it and plug the sprinkler back in. I have replaced the GFCI outlet, but
the new one is doing the same thing. Is the sprinkler box the culprit?
Just want to make sure before spending the time and money to replace it.
Other than keep getting shut off, it is working normally. Also, what if
I just replace the GFCI outlet with a regular outlet? There is a breaker
in the main box that is marked with just this outlet. Interesting to see
if this breaker keeps resetting if a regular outlet is used for the
sprinkler box.

Thanks in advance.