I bought a used spa from a contractor who was doing a job for someone who wanted the tub removed. He told me that it needed a thermostat (which I believe he meant thermistor).

I have filled it with water and it has been running for 17 hours and there is no change in the temp so obviously I have a heating problem.

My spa uses the IQ 2020 control system with the No Fault 6000 heater.

The ready light is not on and the power light is solid red. I understood that a flashing power light would indicate a thermistor problem so I'm not sure what to do at this point.

You could check the voltage at the heater connection to the board to see if the tub is trying to energize the heater. Should be 240VAC (assuming you have a 240V system). A bad flow switch or a bad circ pump will cause the tub not to call for heat.

Hi Denny-

I didn't update my post. It was the NoFault heater that was at fault (make sense!). I replaced the heater, now I am waiting for a control board and I should be set.

Thanks for your reply.