Spa pump won't start on low

[mdiam1980]

I have a CalSpa that has a high and low setting for my pump. When the pump turns on to filter or heat, it just hums and usually doesn't start. If I press the jet button to turn it up to high, then the pump kicks on and I can turn it back down to low and it will continue to run just fine.
Bad start capacitor?? I pulled mine and it has no obvious bulges or leaks.
The tub is currently drained from the winter and I would hate to fill it and end up having to drain it again to remove the pump.
Problem started last summer/fall, so I drained it and winterized it and figured I would deal with it in the spring.
Is there a way to test the capacitor off the pump?

 

[ump107]

There is a way to test the capacitor off the pump, do you have a Volt ohm meter (meter) with a capacitance setting? If you do,
1) SHUT OFF THE POWER TO THE PUMP AT THE BREAKER, THEN CHECK TO ENSURE POWER IS OFF
2) Carefully remove the capacitor, then short the terminals with a screwdriver.
3) Examine the capacitor for bulging or leaking, if either are found replace it to be safe.
4) Look at the capacitor and check the listed capacitance that is listed on the housing usually a number with +-X% next to it.
5) Attach your multimeter leads to the terminals on the capacitor (be careful that you don't short out the capacitor with your hands the shock could be dangerous)
6) Read the display on your mulit-meter if the reading is within the +/-% on the side of the capacitor it is good, if it exceeds the marking or is far less the capacitor needs to be replaced.

There are several videos on youtube that may help you.

 

[mdiam1980]

Mine says 25uF +-10%
Tested it and got 12.94uf
Looks like it IS bad.
Thank You!

 

[ump107]

Your right, it is bad; the acceptable range given what is on the capacitor is 22.5-27.5uf. once you replace your capacitor the pump should start up on low.