Can a Hot Tub Pump Overheat? [Causes, Prevention]


Your hot tub pump can overheat if there’s a blockage caused by debris on the pipes or valves. The blockage could make your pump work extra hard to heat the water, making it extra hot.

The pump may also overheat if it’s situated in a tiny space where it doesn’t get enough cool air. 

You’ll notice the water getting very hot despite maintaining temperatures at optimum levels. In extreme cases, the pump may also start smelling like a burnt substance.

Can you overheat in a hot tub? 

Yes, you can overheat in a hot tub if the water is beyond the optimum temperatures your body can hold. Temperatures above 104 degrees Fahrenheit can give you hot tub hypothermia.

Hot tub hypothermia takes place in several stages. It starts as heat fatigue, then becomes heat exhaustion, and finally heat stroke.

While you’re in the hot tub, you may not notice the temperatures increasing. However, you may start feeling light-headed, dizzy, fainting, and finally passing out.

What happens if the pool pump overheats? 

A pool pump is run through a motor. Under normal circumstances, any electric motor tends to run hot during operation. If you suspect your pool pump is running too hot, then it’s worth checking with an expert because it could also escalate your energy bills. 

Other than increased energy bills, the pump may get damaged, and you’d have to buy a new one altogether.

How do I know if my hot tub pump is bad?

A hot tub pump works hard to maintain clean and hot water in the spa. There are several ways you may know if your hot tub pump is bad. 

Hot tub pump is leaking

  • The pump is producing a humming sound
  • The pump is running, but the water isn’t heating
  • Spa pump is on but not working

If you notice any of these issues, your pump may be bad. Some problems can be fixed at home while others you may have to involve a technician.

The Most Common Cause Of Overheating Hot Tubs

 Here are some of the issues that may cause the pool pump to overheat.

  •  Lack of airflow

Pool pumps emit hot air when in operation. Then, the pump draws in cool air from the surrounding to help it remain cool. When you buy a new pool pump, avoid placing it in a tiny enclosure. Otherwise, you may reduce the lifespan of your pump, which is about seven years.

Usually, a very small space implies that your pump won’t have enough cool air to prevent it from overheating.

  •  Friction

Just like any moving part, friction is bound to occur in different parts of your pool pump.  Too much friction generates heat which may lead to overheating. Greasing the bearings can help reduce heat generated from friction.

  • Resistance to flow (head)

An increase in the resistance to flow, also known as the head, leads to increased energy required to flow water through the system. More energy is lost in such a situation, and consequently, more heat generated, causing your pump to overheat.

The solution to flow resistance is finding the correct size of the pump to match the filters. You cannot have a considerable pump say a three horsepower one for a tiny pool. The flow would cause restriction on the filters as they aren’t a perfect fit. 

How Can I Reduce The Heat In A Hot Tub?

A hot tub is designed such that it can retain most heat to save on energy bills. You may notice some temperature rise in your hot tub during warmer weather, but you need not worry about it. Temperature creeps happen because the excess heat in your hot tub has no way of escaping. Here are some ways you can lower the temperatures in the hot tub.

  • Control panel

You can manually reduce the temperature to about 85 degrees Fahrenheit whenever it’s too hot to bear.

Another trick you can use on your control panel is changing the operating mode from standard to sleeping/economy mode depending on your spa model.

  • Erect a shade

Another effective way to lower temperatures in the hot tub is placing a shade above it. If you cannot move the spa to a place with shade, you can have an umbrella or roofing over the hot tub. 

  • Open the air vents

Hot tubs have air vents that can close or open depending on the weather. Opening these vents can help in releasing the excess heat in the hot tub during summer.

  • Use hot tub chillers 

If it’s super hot where you live, then you can try using some hot tub chillers. Albeit being expensive, chillers are effective at lowering temperatures in a hot tub.

  How To Troubleshoot A Spa Pump

 Here are some of the ways to troubleshoot a spa pump.

  • Spa pump not pumping

The leading cause of having a hot tub pump on but it doesn’t pump is trapped air. You can remove any trapped air quickly. You only need to fit drain plugs. Slowly open the drain plugs after which you should hear a hissing sound as air escapes.

The other reason why your pump could not be pumping is an inadequate water level. If the water level is low, the skimmer may suck in air, causing a blockage. The solution to this problem is filling the hot tub with water until it reaches the middle of the skimmer opening. 

Lastly, your spa pump may fail if there is a blockage. Check to ensure there is nothing stuck on the lines, inside the skimmer, or the drain pipes.

  • Dead hot tub circulation pump 

If the pump doesn’t function at all, first check to confirm that power is switched on. Also, look at the circuit breakers to ensure they aren’t tripped. If this checks out all good, then you need to inspect the problem further. 

The other cause of a dead pump is an error on the control panel. The most common errors are FLO and OH errors. Correct them accordingly. You can use the user manual to check on the procedure to reset the control panel. 

  • Pump making noise

The spa pump may make humming noises if there is air trapped inside. Air is likely to get trapped in the circulation pump while draining the hot tub. To release the air, slowly loosen the union being careful so that the o-ring doesn’t pop out of place.

As the air escapes, you’ll hear a hissing sound. Finally, tighten the union before water starts escaping.

  • Spa pump only high speed 

If you notice that the pump only works at high speed, you need to confirm the low and high-speed terminals’ power supply. Depending on the model of hot tub you have, power should be either 110V or 220V.

If the power supply seems fine, then you can try rotating the timer slightly. After turning the timer clock, switch the thermostat to high, which should solve the problem.

  •  Spa pump only works on low speed

If your spa pump seems to only work under low speed, check that the high-speed switch at the motor’s back is switched on. Also, confirm that the wires and terminals connected to the pump aren’t corroded or rusty.

Editorial Staff

I'm Adnan Sabanovic, the guy behind Hot Tubs Report. I've had a chance to enjoy hot tubs last few years and have really become interested in owning one of them. Nearly every weekend you'll find me spending time with my family or playing sports. If I am not doing that then I'm here writing about tubs on Hot Tubs Report. This blog is a research for my first hot tub which I decided to document and share publically so others can benefit from it as well.

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