How to Heat a Hot Tub Outside
- 1). Place a pool thermometer in the hot tub to periodically monitor the temperature of the water.
- 2). Purchase a hot tub cover that has an R-21 factor for hot tubs that will be kept heated during the winter months in areas with harsh winters. In areas such as Florida and New Mexico, where winters are cold but not harsh, a cover with an R-14 or R-12 factor will keep the heat inside the hot tub.
- 3). Turn the heater on the hot tub to low, which is about 50 degrees Fahrenheit, when the hot tub is not being used, or when it is summer and you don't need much heat. During the summer, the heater can be turned off if you don't need to warm the water.
- 4). Turn the hot tub heater to high heat during the winter 30 minutes before you want to use the tub. Most hot tubs have a high heat setting that is about 104 F. When you are done using the hot tub, turn the heat down to low, and replace the cover.
- 5). Keep the snaps on the cover snapped to the wood shell so the heat stays inside the hot tub.
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