Even on a cold winter day, an outdoor hot tub offers an ideal place to relax. But as temperatures drop, the chances increase that your tub may freeze, especially if you turn of the temperature controls -- which can spell serious damage that requires costly repairs. If your hot tub freezes in the cold weather, work as quickly as possible to thaw it. The process is not a complicated one, but apply caution when defrosting it to protect the tub and prevent fire hazards.
Cut Power and Remove Ice
When you realize you have a frozen hot tub, immediately turn off the power to the hot tub at the circuit breaker so there isn't any electricity flowing through the line at all, and verify to ensure its off. If the thermostat is mechanical, turn it to the off position. Thaw all of the pipes and internal mechanisms before you restore power to the system, especially if you have digital controls for the hot tub, or you risk serious damage to the unit. If the water in the tub is frozen, use an ice pick or other sharp tool to chip away at the ice to create a hole in the center. Boil several pots of water on the stove and pour them into the tub to help melt the ice. After adding each bucket of water, use a wet-dry garage vacuum to remove the ice and water from the tub. Repeat the process until you have emptied the entire tub.
Heat It Up
Even if the water in the tub isn't frozen, its components may freeze during cold weather. To help thaw pipes and other equipment, use a couple of portable electrical space heaters and set them so they face the pump compartment. The tub usually thaws more quickly if you can actually close the heaters inside the equipment area. Don't ever leave the space heaters unattended though, because they can become a potential fire hazard if left alone. Keep the heaters on the pump until it thaws out and is able to turn. If pipes connected to the hot tub are frozen, use an electric hair dryer or heat gun to help thaw them. Hold it several inches away from the pipe and move it in a back and forth motion along the pipe. Keep the tool moving so you don't cause any heat damage to the pipes.
Proceed With Caution
Once you've defrosted the tub and drained it of water and ice, it's time to assess the possible damage. Call a hot tub service professional to examine the tub once it is fully thawed. Your technician will check the entire system for long-term damage from the freeze, such as internal leaks or cracked pipes. If you've caught the freeze in time, you may not have any issues. But broken pipes, even those with hairline cracks, require immediate replacement because they can break or burst.
Prevent Future Freezes
When the tub is operational again, take steps to prevent future freezing. Verify if your model has a freeze protection mode to monitor the temperature and turn the circulation pump on if the water is close to freezing. Check to ensure the mode is engaged as winter approaches. If your hot tub doesn't have a freeze protection mode, ensure that the pump is turned on when a cold spell is expected, keeping the tub's jets open and moving the water through the system, which prevents freezing. If you don't plan to use the tub for three months or longer, winterize it by draining the water and blowing air through the lines to force any water out of the hoses, pipes and other equipment.