[Sundance 850 Pump Cycling By Itself]

2001 Sundance, does it have the 3 button remote control panel? If so, it is probably the panel causing the problem. (water in pump button). Perform at our own risk! Turn off power, unplug remote panel loom only inside control box, plug power back in and see what happens. If it acts normal you can replace control panel or go with out. If it still acts weird then it may be the pump button on main control panel. Only way to test that one is with another control panel. Good Luck!

thanks for the leads. It has the larger control panel with the LCD display, but I think it could still possibly be water inside that that is causing this, so I will try unplugging it to see what happens.

What do you mean by the "pump button" on the main control panel? Could it be a stuck relay?

[Sundance 850 Pump Cycling By Itself]

Could be as PS said above, but also could be low voltage. Get a meter on the incoming power right at the control board. See if it drops more than 10%. This can cause digital circuits to go nuts.

I am hoping it is not the circuit board (obviously). I did take the motor off line and the controller still cycled the motor's relay, so the load of the motor is not pulling the voltage down. When you say to check for a drop of more than 10%, are you talking about the drop the motor would have caused? Do you know what the DC level on the board should be? Is is possible to get a schematic for these boards (more than just the wiring potion) from anyone?

Thanks,

Don

[Sundance 850 Pump Cycling By Itself]

I have a Sundance spa with a series 750/850 controller, made in 2001. Out of no where it has started to continuously cycle the 2 speed pump on and off, about once every minute. It turns on the pump in low speed, about 10 seconds later it goes to high speed, then after running on high speed it shuts the pump off after about 20 seconds, waits about 1 minute and does this all over again. Have tried turning off the power over night, no help. Temperature sensor seems to be working accurately, flow switch seems OK. I have tried setting he automatic cycles to off and it makes no difference. When the pump kicks in I can not turn it off at the control pane, but when it is off I can manually switch the pump on and off at the control panel. Otherwise the controller seems normal.

Help!!!! Please!!!!