Welcome to our forum.
yes even under standard mode the circ pump DOES NOT work when the temp is at the set temp. I think the circ pump, the heater and the ozonator are all tied together or something..
Do you by any chance participate in the "Power Company" program that allows them to "throttle back" power from certain areas at certain peak times? If so, I would speculate that your hot tub is on one of those circuits that the power company "conditions" (i.e. cuts power too) during certain periods of time. This would easily explain the condition and would also explain why you don't see anything else in the house loose power (clock, etc). As for 24-hour circulation.... There's a REASON it's called a 24-hour pump. It operates 24x7x365. At least mine does. Now, the ozonator does kick in and out based on the tubs own logic butthe pump itself runs 100% of the time. Do you have the same (24hr pump not working) problem when the tub is running under "standard" mode?I have a 2003 Jacuzzi J-370 which uses the same (pump & electronic controls) components as the Sundance models of most years.