I agree.
BTW ...Is the problem more common after it rains?
Classic t/s is to divide and conquer. Disconnect central vac and observe.
Perhaps disconnect all load lines from GFCI c/b ... and observe.

"RBM" rmottola1(remove wrote in message
...
I agree with Doug, whenever I've had intermittent tripping of GFCI
breakers,
its always turned out to be an outside outlet with water getting in. Also
I'd question a central vac that's not on a dedicated circuit. The ones
I've
wired require a 20 amp circuit by themselves
"Doug Miller" wrote in message
news
In article , Rob Mitchell
wrote:
I am having a problem with my GFI circuit breaker. It trips. Now
perhaps it is working correctly, but I'm not sure. The circuit controls
the central vac in the garage (and a couple of outlets in the garage and
exterior of the house.)

What's plugged into those outlets?

Have you checked the outdoor outlets for moisture infiltration or
condensation?