Hot Tub Pump Problems: Identifying the Cause

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  • 1-8 hours
  • Intermediate
  • 1-1,000

Hot tub problems come in all shapes and sizes. What follows are some of the most common pump problems that arise when hot tub troubleshooting.

No Low-Speed Pump

Check to see if the high speed still works. Then check the power for correct voltage. If the high speed doesn’t work but the voltage is correct, then you have to test for power at the pump air switch input next. If there’s no power here, then there’s probably an inside wiring problem. If the high speed does work choose thermostat mode and turn it completely clockwise. If the low speed now works, turn the thermostat completely counterclockwise and turn the timer on completely. If the low speed does work with the thermostat but doesn’t work with the timer then change the timer. If the low speed works with the timer but not with the thermostat then bypass the thermostat’s connection and change it.

Constant Low Speed

Turn off the timer. Set the thermostat completely counterclockwise. Put hot tub in time clock mode. Check to see the motor still changes over by choosing high speed. If it doesn’t, turn timer and then thermostat one at a time completely clockwise. If high speed turns on with either then swap wires on the motor because the low and high-speed contacts are backward. If the motor does change over to high speed, first go again to low speed, then remove one of the wires from its coil. If this discontinues low speed then change the wire. If the low speed does not work now then you need to change the timer.

No High-Speed Pump

First, choose high speed. If the motor doesn’t work, turn the thermostat and timer completely clockwise. If high speed works with either, change black and red contact wires at the back of the pump. If high speed doesn’t work with either, then check the voltage on the motor. If the voltage is right, then you need to change the pump motor entirely. If the voltage isn’t right, examine the pump air switch for power. If the power is correct here, then the terminal or cord is damaged.

Both Speeds Simultaneously

If high and low speeds are operating simultaneously, then remove the pump cord and then examine the pump air switch for power. If both have power then there must be wiring trouble inside which has caused a short. If both speeds don’t have power then examine the pump cord for problems. If the cord is fine you have to change the motor.

Reduced Water Flow

First, examine and clean your filters. If the filters are older than a year exchange them with new ones. If water flow is still reduced then disengage power to the hot tub and then detach the section end pipe and look inside for and remove all debris. See if the impeller is broken and replace it if needed.

No Water Flow

Disengage power. Examine the wet end for the blocked or damaged impeller. If the impeller is fine, then check that its shaft spins freely. If the shaft is fine, check the capacitor and replace it if needed.

Hopefully, with a bit elbow grease and maintenance, you are now able to once again enjoy your hot tub trouble-free for a long time to come.