Hot tub pump not working or humming: causes and fixes

Safety first. Turn the power off at the breaker before you open the equipment bay, and never open the control box or run the spa on an extension cord. Voltage and fuse tests are for a spa tech or licensed electrician.

Common symptoms

You press the jets button and nothing happens: no sound, no water.
The pump hums, but the jets never start.
The pump works on low speed but not high, or on high but not low.
The pump runs for a while, shuts itself off, then works again later.
The motor runs, but no water comes out of the jets.
The pump grinds or screeches, or water drips under it.

Quick checks before anything else

The control panel lights up. A blank panel means no power to the spa.
The GFCI has not tripped. Press TEST, wait 30 seconds, then press RESET.
The spa is not in hold or standby mode, which stops the pumps on purpose.
The water is above the highest jet and the filter is clean.
The vents and the air gap at the bottom of the cabinet are not blocked by grass, soil or stored items.
The spa is not plugged into an extension cord.

Why does a hot tub pump stop working?

No power A tripped GFCI or breaker. The panel is blank and nothing runs.
Time-out or hold mode The pump stops by design after a set time, or while you service the filter.
Thermal overload A heat switch in the motor shuts it off when it runs too hot, then lets it restart after it cools.
Low voltage The motor hums, runs hot, or keeps cutting out, often worse when everything runs at once.
Jammed impeller or worn bearings The impeller is the spinning wheel that throws the water. A jam gives a hum with no spin; worn bearings grind.
Blown fuse or one dead speed One speed works and the other does not, or one pump is dead while the rest of the tub works.

First split: is the pump getting power?

Press the jets buttonCheck that the pump icon or light comes on
Listen at the equipment doorPower off at the breaker before you open it
Do you hear the motor when you press the button?

Yes: if it hums but water does not move, switch it off and go to steps 7 to 9. If it runs but the jets are dead, it is most likely air or flow (step 6).

No: check power, time-outs, hold mode and a hot motor first (steps 1 to 5). Fuses and wiring come after that, and those are for a tech.

Step-by-step: hot tub pump not working

We go from free resets to checks that need a meter. Steps 8 and 9 involve live wiring and belong to a spa tech or electrician. For how the pump, jets and GFCI fit together, see our hot tub pump, jets and GFCI guide.

Confirm power at the panel. If the panel is blank, check the GFCI and the house breaker. Hot Spring says a GFCI that will not reset can mean a ground fault (a short to ground) in the spa’s electrical parts, which needs a service tech. A tripped house breaker can mean an overloaded circuit or a ground fault in the wiring to the spa, which needs an electrician. If it keeps tripping, read hot tub GFCI keeps tripping before you reset it again.
Reset the GFCI the right way. Press TEST, wait 30 seconds, then press RESET. If the GFCI trips again right away, stop resetting it.
Rule out time-outs and hold mode. A pump you start with a button shuts off after a set time. Gecko’s in.k200 keypad does this after 20 minutes by default, and Balboa says pump 1 low speed can time out after as long as 4 hours on some systems. Balboa’s hold mode stops the pumps for 1 hour while you service the filter. Press the button again, or exit hold mode, and see if the pump starts.
Let a hot pump cool. Hot Spring’s jet pumps have a thermal overload switch that shuts the motor off to protect it, and Waterway says its pumps restart once they cool. In a newer spa, Hot Spring blames a blocked cooling vent, a sensitive overload switch, a tight new pump that runs warm until broken in, or low voltage from an extension cord or thin wiring. Clear the vents, let the motor cool, and try again.
Check the circulation pump. Many tubs have a small circulation pump (circ pump) that filters and heats, separate from the jet pump. Hot Spring’s circ pump is water-cooled, so it has a thermal cut-off that trips if it runs hot with no water. To reset it, disconnect power to the spa and let the pump cool. Hot Spring ties repeat trips to a clogged filter, a blocked pipe, draining without cutting the power first, or an airlock. Gecko’s guide starts a circ pump for testing by setting the temperature 2 F above the water temperature.
Prime the pump. If the motor runs but no water comes out, air is trapped in it. Turn the power off and on: Balboa controls then enter priming mode, where you run each pump on high. Balboa says not to let a pump run unprimed for more than 2 minutes, and to cycle it off and on no more than 5 times. Our hot tub jets not working guide walks through the full airlock fix.
Do not leave a humming pump on. A hum with no water moving means the motor has power but the shaft cannot turn. Switch it off. Hayward’s pool pump manual lists a jammed impeller as the cause of a motor that hums but will not start, and says to have a qualified repair pro open the pump and clear it. Spa and pool pumps share this design, so our pool pump humming guide covers the same fault in more depth.
Have the voltage checked. Balboa says most problems with spa control systems come from low voltage. Its acceptable range is 108 to 132 V on a 120 V system and 216 to 264 V on a 240 V system, measured with the pumps, heater, blower and light all running. The reading at the spa should differ from the reading at the breaker panel by no more than 2 percent (5 V). If it is outside that range, Balboa says to call an electrician or the electric company.
Test each speed and fuse. This is a tech’s job inside the control box. Gecko’s guide says that if a pump does not work on either speed, replace the fuse that feeds it. If it runs on only one speed, measure the voltage at that speed’s output: 120 V for a 120 V pump, 240 V for a 240 V pump. Good voltage with no motion points to the cables or the pump. No voltage points to the control. Balboa adds that when the main power fuse blows, the pump is the most likely cause.
Listen for bearings and look for leaks. Waterway says noisy bearings come from age, strong chemicals and heat, and that the fix is new bearings or a new motor. It also warns that a leaking pump seal can damage the front motor bearing, so fix drips under the pump quickly. Hot Spring says a pump that shuts itself off in an older spa can mean worn motor bearings.

Stop. Turn the power off at the breaker before you open the equipment bay. Do not open the control box: Balboa and Hot Spring both say there are no user-serviceable parts inside, and Balboa says installation must be done by a licensed electrician. Never run a spa on an extension cord.

Jet pump vs circulation pump: which one failed?

Many tubs pair one or two jet pumps with a small circ pump. Tubs without a circ pump use the jet pump’s low speed to filter and heat.

What you notice	Likely pump	Next step
Jets dead, but the water still heats	Jet pump	Steps 3, 4, 7 and 9
Jets work, but no heat and a flow message	Circ pump or jet pump low speed	Steps 5 and 6
Nothing runs, panel blank	Neither; it is power	Steps 1 and 2
Works on one speed only	Two-speed jet pump	Step 9

The panel messages differ by brand. Balboa spells out flow problems as HFL, LF and dr, Gecko shows FLO, and Hot Spring blinks its indicator lights. Our hot tub error codes guide explains the common ones. Before you order a pump, write down the spa model, the control pack model and the pump’s label.

When to call a pool or spa pro

The GFCI will not reset, or it trips as soon as the pump starts.
The pump hums and will not spin, or grinds.
The pump keeps shutting off after short runs with clear vents. Hot Spring says to call a qualified tech at that point.
One speed or one pump is dead and needs fuse or voltage tests.
Water is leaking from the pump body or seal.
Balboa shows a stuck pump message. Its guide says to power down the spa, stay out of the water, and contact service.

Common questions

What are the common reasons why my hot tub pump isn’t working?

The most common reasons are a tripped GFCI, a pump that timed out or sits in hold mode, a tripped thermal overload, and air trapped after a refill. After those come low voltage, a jammed impeller, a blown fuse and worn bearings. The first four are free to fix, so start there.

How do I reset the pump in my hot tub?

Turn the power off at the breaker, wait at least 30 seconds, and turn it back on. That clears many faults, lets a thermal overload cool, and on Balboa controls starts a new priming session. Most spa pumps have no reset button of their own.

How do I tell if a hot tub motor is bad?

Rule out power, heat and air first. If the motor gets the right voltage but hums without turning, grinds, or keeps shutting off after it cools, the motor or its bearings are likely failing. A tech confirms it with a voltage test at the pump’s output.

How do I know if my hot tub pressure switch is bad?

Rule out flow first, because a pressure switch usually opens for a real reason. Hot Spring says its switch opens because of a clogged filter, a blocked pipe, draining without cutting power, an airlock, or a circ pump that is not working, and that it closes again once flow is back. If the jets are strong and the filter is clean but the flow message stays, have a tech test the switch.

How much does it cost to fix a pump in a hot tub?

It depends on what failed. A reset, a cleaned vent or a cleared airlock costs nothing, while a fuse, a seal, bearings, a motor or a full pump each cost more and vary by model. Doing the free checks first and giving the tech your spa and pump model numbers keeps the visit short.

What is the life expectancy of a hot tub pump?

Balboa, Gecko, Hot Spring and Waterway do not publish a pump lifespan in the documents we checked. Hot Spring links a pump that shuts itself off in an older spa to worn bearings, and Waterway says bearings can be replaced or the whole motor swapped.