The factory threshold on most modern hot tubs is 104-degrees Fahrenheit. According to the Consumer Product Safety Commission, temperatures above this limit are harmful. At just 106 degrees, a person can suffer from heat stroke—a condition fatal to some adults.
Most people find 104 degrees too hot anyway. Hot tubs average 100 to 102 degrees in temperature, though many remain in the 90s. You should experiment with the temperature of your spa at different times of the day. You may also need to adjust it when the seasons change.
Take Other Bathers into Account
Consider who will use the tub and how that might affect the temperature you choose.
- Children under 16. Kids are more sensitive to heat. Their bodies cannot regulate temperature through perspiration. For this reason, hot tubs should never exceed 90 degrees when kids are soaking.
- Pregnant Women. Regardless of temperature, there are circumstances where pregnant women should avoid spas. For detailed information, please click here.
- Bathers with Medical Conditions. People on medication may suffer from drowsiness in warm water. Worse, some may experience breathlessness and chest tightness.
The number of people in a hot tub affects its temperature. Generally, the more people, the cooler the water feels. Be careful when adjusting the hot tub’s temperature: you may find the water unbearable after bathers leave it.
Keep Your Temperatures Consistent
Once you’ve discovered the ideal temperature, keep the thermostat in one place. Some folks like to turn the temperature down to conserve energy, then elevate it a few hours before going in. This stresses the heating elements and circuit boards. Over time, doing this could even increase your operational costs. Lowering the temperature only makes sense for extended periods (i.e. a vacation).
A quality hot tub cover can help regulate the temperature of your hot tub. It preserves the heat inside, helping reduce the amount of energy used generating new heat.