Our jacuzzi z-140 (purchased in 1999) is remaining at a high temperature despite us turning it down completely. The topside temperature/jets/lights control is directly on the tub and does not indicate temperature. It is not digital, just a knob to turn for temperature, a button for jets/lights and a light to indicate heating. Any suggestions? We turned off the circuit breaker so as not to keep heating it while we're away. Thanks!

Hello out there! We continue to have the same problem. We have 230 volts. Any suggestions would be greatly appreciated! After leaving it off for several days (by turning off at circuit breaker) it did cool down. I turned it on yesterday and the same thing is happening.

I am new to this but in my opinion it sounds like you have a bad thermostat.

The "normal" problems are a thermostat is stuck shut, or the heater contator / relay stuck shut sending power to the heater all the time. To test the t-stat's function, turning it up and down should turn on low speed on the pump when calling for heat, and turn off low speed when there is no call for heat. if you have a volt meter you should be able to verify power at the element and no power at the element.

review of heater testing:

Make sure the heater element is getting/not getting voltage, to check this put one meter test lead on each electrical terminal of the element and see if you have full voltage.

Do an AMP check on the heater when you believe it is heating, a 220 element will draw around 20 amps, a 115 element will draw about 10 amps.


Is the spa cycling at all, if you turn the thermostat all the way down does low speed pump turn off, turning up the thermostat does the low speed come on?