Strange GFCI problem... HELP!!
I hope someone can help us on our GFCI problem.
I have two GFCI with separate circuit breaker. On the 1st GFCI I have 2 pond pumps connected to it. The pumps have been working fine without tripping the GFCI for 2 years. About a month ago the 1st GFCI tripped and after some testing I found out that I can only connect one of the pumps at a time. Connecting both pumps will trip the 1st GFCI.
Initially I thought the problem was w/ the pumps but when I connect both pumps to the 2nd GFCI it worked fine without tripping it. I also replaced the 1st GFCI with a new one but the problem still occurs.
Any suggestion on what can cause this problem. There are no other appliances connected to either GFCI. Both GFCI are located indoor.
Thanks in advance for the help.