I have a 2000 Sundance Cameo. I had a "FLO" error and replaced the Flow switch which solved that problem. Later on, the tub had been tripping the GFCI every so often and had a small leak (I'm guessing about 1-2 gallons a day), and I never knew why. This went on for almost a year. I just kept adding water to the tub. THe circulation pump went out and I replaced it. Things worked well although I still had the small leak and occassional GFCI trip (very sensitive switch, especially during lighting storms).

This winter I went out and the tub was shut off and the flow lines by the flow switch casing had broke and the tub was about 1/3rd drained. I immediately drained the water out of the tub (it is outdoors in Nebraska) and opened all valves to keep it from freezing. I ordered and replaced the flow switch assembly, but when filling up the tub, I noticed it was still leaking profoundly from the heater housing onto the circulation pump. I believe this was my original problem that may have been causing the GFCI to trip. I redrained the tub, took out the heater assembly, and took it apart and sure enough, there was a 1/8" sized-hole in the heater housing. I'm guessing the hole got worst but that it was the source of my original leak and GFCI tripping problem as the heater sits directly above the circulation pump. Probably why the old circulation pump went bad also.

I ordered a new heater assembly (another two weeks went by with the hot-tub drained again in cold weather). I installed the heater, refilled the tub, and hit the GFCI. The pumps sounded off, but things appeared frozen. I immediately shut the thing off and decided I better wait until warmer weather when the tub could thaw out.


When the weather warmed up, I refilled the tub and reset the GFCI. The main pumps worked and pumped water water. But after about 30 seconds, the heater housing melted to an ugly mass and I had ugly burnt plastic smelling smoke. That brand new $200 heater assembly was ruined.

My questions are:
1. why did that happen? I thought the heater wasn't even suppose to turn on unless the circulation pump was pushing water through it and making the flow switch contacts touch. The only thing I can think of is that the flow switch was faulty (shorted), but then why didn't the high-limit sensor switch shut it off before that much damage was done?

2. How can I test the High-limit sensor switch?

3. What's the best way to test my fairly new circulation pump?

I have ordered a new heater assembly and will install it, but I will NOT hook up the main leads to it until I can verify things are in order. I don't want another melt-down.

Update:
Got the parts. I replaced the flow switch, high-limit sensor, and temp sensor (they were over 9 years old anyway). All new parts tested out fine. I tested the old sensors/switch and they tested out fine also. I'm hoping my circuit board isn't the problem. I will get the heater installed and fill the tub up and post back with some voltage readings on the 'disconnected' heater element. I will also retest the flow switch while the tub is in operation (circ. pump on/off).

Ok, I got the heater installed and started checking the pumps. The two main pumps and the blower seem to work fine. I noticed that when the 2-speed main pump is on, that the 'flow switch' closes and the heater circuit turns on. I can actually hear the breaker clicking. I guess my breakers/relays are okay. While the 2-speed motor is running (flow switch closed, heater circuit on) my voltage is 240vAC across the heater terminals (Red/Black 240vac, Red/Ground 120vac, Black/Ground 120vac). When it is off, I have a "FLO" error and the voltage is 40vAC across the heater terminals (Red/Black 40vac, Red/Ground 120vac, Black/Ground 0vac).
Obviously, the circulation pump isn't kicking on. The voltage levels on the circulation pump are as follows:

Heater Circuit on thanx to the 2-speed main pump: (Black/White 240vac, Black/Ground 120vac, White/Ground 120vac).

Heater Circuit off: (Black/White 240vac, Black/Ground 120vac, White/Ground 120vac).

Should the circulation pump always have 240vac across its leads? Does this indicate that my circ. pump is defective? It is only 1 year old. Here's a link to the model I purchased to replace the original. My tub is a 2000 Sundance Cameo, Controller 850LCD.

http://www.spaandpoolsource.com/6000-125sundancespascirculationpump240voltnewcirculationpumpfromsundanceusedonall240voltsystemsfrom1995-2008.aspx

I believe that circ pump should be on 24/7 - so you should have 240 accross the leads - If you do have 240 and the pump isn't running you may just have an airlock in the pump - if you don't have 240 then something else is going on - possibly a circuit board. Pete http://www.makesmeshutter.com use this advise at your own risk

I have 240vac across the circ. pump leads all the time. The circ pump feeds off of the 2-speed motor, which is why the flow switch can close if I run the 2-speed motor. But, the circ pump never runs. Since the 2-speed flows through the circ pump then through the heater and then through the flow switch on its way out, wouldn't that mean that I couldn't have an air lock? I loosened the clamps on the hoses and let a little water drain from both sides on the circ pump. It still won't kick on. Don't even hear it hum or try to kick on. This pump is only 13 months old. I thought Laing was suppose to be such a good pump.

I do know I'll never buy a Sundance again. They're suppose to be so great but I've replaced 1 main pump, a control panel, flow switch twice, circ pump once, heater once all in addition to replacing the heater, flow switch, temp sensor, high-limit sensor for this latest problem. Now it looks as if I have to replace the circ pump again. I'm getting pretty bummed with this hottub. I'm about ready to start scrapping it and placing parts on Craig's list!!

I'm not positive but I think the circ pump should have it's own plumbing line independent of any jet pump. I may be wrong. Check voltage on the back of the circ pump itself to make sure the cord is good. If you have voltage there and the pump won't even hum or feel like it's trying to run then I would think a bad circ pump. Pete use this advise at your own risk http://www.makesmeshutter.com

I agree, I need a circ. pump. But I'm still baffled on why my heater melted (burned, melted, deformed, smoked, smelly, plastic housing). If the circ pump is bad, then the flow switch should've been opened causing the heater circuit to turn off. The only way the flow switch could've closed is with the 2-speed motor pumping water through the heater core, in which case the heater shouldn'tve melted. Baffled.

My circ pump plumping is about a 3/4" line feeding off of the main 2-3"?line off of the output of the 2-speed motor. I think I've read in other forum topics about how their circ pumps feed off of other plumping, while others say theirs is stand-alone and feeds off of a hose connected to the Spa wall.

With the HotSpring I deal with mostly the circ pump is it's own circuit per say. Tiger Rivers run kind of like yours using the jet pump also but have a water check valve in the 3/4" line of the circ pump so that when the jet pump turns on the check valve closes. I would guess the heater may have dry fired which would lead me to a flow switch problem. I'm pretty baffled also. Try calling Jacuzzi - they are usually good on talking to customers. Pete use this advise at your own risk http://www.makesmeshutter.com

I replaced the circ pump and all seems well. I have control over the temperature; the tub is heating up fine. Must've had a dry-fire last time, possible caused by not priming the old circ pump first. I still say the old flow switch must've been acting up, even though it tested okay after I replaced it.

Great job. I would also say the flow switch was bad - it almost had to be if the heater dry fired. Happy Soaking Pete http://www.makesmeshutter.com http://www.floridahotspring.com