jetbird

I just purchased an Envoy Hot Springs spa and have not installed it yet. I own a vacation home in wyoming(gets really cold), and plan to the use the tub only a couple months out of the year. I want to be able to quickly winterize the tub, and be able to fill and start using without much effort. My plan is to drain the hot tub using the two drain valves, dry out the inside of the tub, and put small thermostatically controlled heaters; one in the enclosed tub area and one in the pump cavity both set to 50F. Do I still risk freezing if I do this? Thanks, Jeff