Locate the main drain valve and remove the cap. Attach a garden hose and open the valve. The spa and plumbing lines will drain by gravitational flow. Remember, the most important part of winterizing a hot tub or spa is to remove all water. If water freezes inside of your spa, it will expand and damage the unit.. Most of a hot tub's heat is lost through the top of the spa, you know because heat rises. The cheapest and most effective way to add insulation is to use a floating thermo-blanket - it simply lays on the spa water under the cover to help hold in heat.. Keep in mind that a thermal blanket might not make much of a difference if your spa cover is old and heavy.
If you live in an area of the world with four seasons, you should consider winterizing your hot tub during the cold months of the year. Similar to the winterization process for pools, it protects the tub from taking on unnecessary damage due to non-use.. However, with a higher water temperature in hot tubs, many spa owners choose to keep their tub open so they can use it over the winter months.. Begin by putting your hot tub's cover on, and then plug the hot tub back in and turn it on. Once the hot tub is covered and turned on, activate the air blower function and let it run for about a minute to flush the water out of the channels. After draining the air blowers, safely turn off and unplug your hot tub once again. 4.