Hello RD - thanks for the reply!
I live in the north Boulder Foothills, and volunteer with Boulder Mountain Fire. I first responded to the Middle Fork Fire (just SW of Longmont and just east of the Greenbriar restaurant) on Thursday, and didn't get released from that until later at night and didn't make the cut to the Marshall Fire, but instead was backfill for my department who sent an engine once I returned from Middle Fork. I did end up out in Louisville later that night to shuttle a paramedic-nurse friend after a vehicle accident, so got sleep deprived nonetheless. My Louisville rentals, my ex's house, my daughter's house survived, but not my daughter's mom's house nor about eight other families that I know. Or a thousand others.
Attached are photos. I did get a trough heater this morning to protect against freezing in the meantime. And doh, you are suggesting a systematic approach?! I'll search for the heater connection first... and as of now the 110V breaker is unable to be reset / trips immediately. I can just go get a new breaker. The heat is provided by 220V, and that breaker has not been tripping.
The reason I don't initially suspect the breaker is because it had been tripping in response to overflow splashing... as if water goes down the jet diverter knob and drips onto equipment??? I can re-grease that diverter or just RTV it completely - I never use it.
Now we are seeing crust and moisture buildup around the equipment compartment that was not there a couple years ago. This tub is showing it's age, but I would like to make it serviceable for another year or two. When the deck gets replaced, I'll get another Hotsprings.
Edit: Today the 110V breaker stays on with all equipment connected, and since there are little bubbles rising inside the tub middle, I'm hoping that circulation and heat are operating. So much for my systematic troubleshooting skills. Perhaps the open equipment cover allowed for some internal drying out? Stand by for updates; I have not run the jet pump, and won't until I see the tub up to temperature.