I have a '99 Hot Spring Grandee (220v) that was just moved and connected to a new breaker box. I planned on filling it w/water tonight, but the temp is going to drop to 23 degrees F. I don't want to fill it up if I'm not certain that the heater will work and when I try to move 20 AMP GFCI breaker on it won't stay on. Do the GFCIs not stay on if the tub isn't full of water? The 30 AMP GFCI will stay on, but I don't see any light on my front control panel. To compond matters, the tub has about one inch of water in it already so I'm afraid it might freeze in the hoses or heater if I don't fill it up and get the heater working. Can anyone advice me on whether filling it w/water will enable the GFCI to work? I had the no-fault heater replaced a year ago it that helps diagnose the problem and haven't had any problems since.

Thanks for helping a fellow spa lover out!!