Troubleshooting a Hot Tub That Won’t Get Hot

On cold winter days, a soothing soak in a hot tub can be just the thing to warm you up and calm you down. But only if your hot tub is actually … hot. If the water in your hot tub doesn’t live up to its name, a number of common culprits could be at fault.

Culprit #1: Low water flow                         

Your hot tub’s heating element requires a certain level of water flow in order to protect itself from over-heating. If the water flow is too low, it will automatically shut itself off. A dirty water filter is usually responsible for causing low flow—water can’t flow freely through a clogged filter. Remove the filter cartridge and clean it thoroughly. If that doesn’t solve the problem, you may need to explore more serious issues like broken pumps, valves, or clogged pipes.

Culprit #2: No power

It’s possible that your tub isn’t heating up because it’s not actually receiving any power. Unplug the tub, and then check your circuit breaker for signs of a blown fuse. If all seems fine, test the outlet. If that, too, seems to be functional, check the tub itself. Hot tubs come with something called a hi-limit switch that turns off power supply to the tub when the water becomes too hot. Reset this and plug the tub back in. If your hi-limit switch seems to be tripping frequently, you’ll want to have an expert check it out to identify the underlying problem.

Culprit #3: Malfunctioning thermostat

A malfunctioning thermostat will turn off your tub’s heating element too soon if it mistakenly determines that the water has reached the appropriate temperature. You may only need to simply reset the thermostat, but in some cases it will need to be replaced.

Culprit #4: Cover needs replacing

 The cover over your hot tub isn’t just there to keep leaves and other contaminants out of your water. It’s also there to trap heat and keep your hot tub at a cozy temperature. If your hot tub cover is cracked or damaged, heat will escape and your tub will have a harder time reaching and maintaining an ideal temperature. Mend or replace the cover to ensure it can effectively perform its duty.

Culprit #5: Broken heating element

The heating element is the machinery responsible for heating your tub. A broken heating element equals no hot water. If you’ve tried troubleshooting all of the above culprits and your tub still isn’t heating up, you may have a broken heating element on your hands. This repair is more sophisticated and best left to a professional.

Always be very cautious when troubleshooting your hot tub—water and electricity are never a safe combination. Unplug the tub before attempting to perform any repairs, even if they seem minor. If you’re at all unsure what to do or are worried about safety, err on the side of caution. It’s safer for you–and your machine–to contact an expert plumber to handle the problem for you.

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