2002 Hotsprings Vanguard Question

[steveIII]

I recently acquired a 2002 Hotsprings Vanguard that was in excellent shape. I'd previously owned a Leisure Bay 10000 series for 20 years so I'm somewhat familiar with the upkeep of spas.

Last week, the wind was blowing really hard and I noticed on 3 occasions the cover, which I hadn't locked down, had blown up and there was alot of debri,. leaves, etc in the hot-tub. I shut the tub off, and cleaned out all the debris and changed my filters with the 4 new replacements that I had. I used an old piece of a garden hose to suction or vacuum debris from the bottom of the tub. The water level after vacuuming debris was still over halfway above the tile-line, and certainly covered the top of the highest jets.

I turned the tub on successfully and went about my business. There was a power outage locally about an hour later, and when the power came back on, I walked by the tub and noticed the green ready light blinking. I turned off the breaker for a couple of minutes, and then flipped the breaker on. This time I got a red power light blinking. Uh-Oh! The manual indicated this was a Heater High Limit thermostat being tripped. I checked the High Limit Switch on top of the heater and it had not popped up and tripped. Double uh-oh!

I turned the power back off for a half hour or so, the flipped it back on. The Slo-flo pump was slow in starting so I thought maybe some air had gotten into the line. I inserted my water hose into the gray filter stand and filled the spa up to the top of the tile line. I turned it back on, and took the water line loose just past the FreshWaterIII Ozone injector and there was a little bit of air in the lines. The Slo-flo pump kicked on and I thought I was back in business as I felt the NoFault 6000 heater warming up. The water temp went from 81 or so up to 87 and that was the max. This told me that the heater must be failing which seemed odd as it is a "NoFault" Heater.

I plugged off the water lines and took the Thermistors out and inspected them. There were no visible issues. I then took the NoFault 6000 heater off and took it apart to inspect, thinking I would find a burned out element. There was no visible burn marks. I took the High Limit Switch off, and then took a lighter and warmed the bottom of the switch. It popped up telling me that the thing was working. I cooled it down with a piece of ice and it reset. Next I cut one end of the heater line, thinking I could pull the heating element out of the tubing but it seemed to be to difficult. I wished then that I hadn't cut the line and this took a long time to solder back together. The inside of the nofault heater tubes was covered in a silvery muck!! I took some white vinegar and cleaned the inside of the heating tubes up. I finally put all this back together, and successfully attached all the plumbing and electrical lines. This took almost 10 hours to complete all the above as I am an amateur and curious as to how things work.

When I turned the power back on, first the 20 amp, then the 30 amp heater breakers, lo and behold, the heater started working and has been running flawlessly now for 3 days!

My question to any moderator or pro is just exactly what the hell did I do to fix this thing? My best uneducated guess is that my High Limit Switch was stuck in never-never land and by taking it off and applying heat to it made the thing work again. This is the only reason other that burn element that I can think of. Thoughts anyone??

Steve