I just purchased a house with a 5 year old jetted spa.

It was drained from the main drain prior to the winter, but not winterized any further, and powered off. A small amount of ice is on the bottom of the tub, maybe an inch.

I connected the power, and it hummed for a second and shut down, so I'm assuming at least something is frozen, probably the pump. It didn't trip any breakers or GFI's, so I'm assuming it was some internal relay that kicks off, or at least that is what I hope.

Any chance that filling the empty spa with, say 50 gallons of hot water from my water heater will thaw out the spa and the pump and get things going again, or do they almost always bust a pipe or something when they freeze like that?

Advice? Wait till spring? Try the hot water?