Secure your spa by closing and latching any doors. Often thumbscrews are present to make it easy to secure doors. You might want to consider covering your spa for the winter with a cover that blankets both the water surface and cabinets. Using a cover like this helps keep snow melt or rain water from seeping into the spa and causing freeze damage.
A close up detail of the radiator covers in the 25th Avenue project in North Minneapolis. Originally this home featured radiators, but Nicole Curtis had the space converted to a heat system, while deciding to keep the radiator covers.