I replaced a working ceiling fan in our bedroom with a new fan. Everything was working fine up to then. The circuit is on a GFCI in the panel. When I attach to ground from the fan to the ground line on the circuit it trips the GFCI and it can not be reset. As soon as I disconnect the ground, the GFCI can be reset the fan and lights work fine. What would cause this other than that there is a short in the new fan? There was no problem with the circuit while the previous fan was installed (and grounded). Finally, the fan only has a remote control, no pull chains, and is 12 feet above the floor so I assume it is safe to operate without the ground line connected. Correct? Thanks in advance for explanations!