1. Hot Springs Jetsetter, 2002
2. 230v service, 30a breaker for heater, 20a for pumps and control
3. IQ 2020 control
4. Unsure what's meant by "topside control", there are some manual valves, and a basic digital control panel on the side for heat, light, jet on/off.
5. 1 jet pump (115/230 convertible?), 1 115v circulator, both single speed.
6. Thermostat control integral with control panel on side.
7. Heater: Laing "trombone" or "tri-bend" 6000 watt 230v heater.
We bought the house in December 2004, spa was about 2 years old and came with the house. It has been working great up until about mid summer, although it seems that the pressure safety button on the heater was very touchy and would pop out without much provocation, if the level got low, etc, and of course there would be no heat until I took the panel off and reset it. The high limit on the control has NEVER tripped, i.e. it has never been a problem.
The heater tests at an expected 9.5ohms and heats great, but the pressure button has gotten more and more prone to popping out and the circulator has gotten noiser in the past few months. It has finally gotten to the point where I cannot heat a water change without having it pop out, especially as I get closer to the 100° set point.
I have had some calcium problems with the last couple of water changes and there is some scale inside everything. I have been meticulous about keeping the filters clean regardless, I have cleaned them with the soak type acid repeatedly and even replaced them to make sure that they were not causing a restriction. I am taking a water sample of my softened water to the spa place today to have them analyze it, and I will use some vinegar or spa shell cleaner on a rag to attempt to clean up the little bit of scale on the shell, so I think that's reasonably under control. Hopefully the soft water will help remedy this situation as I was using unsoftened water before.
I drained the tub again and removed the heater to examine. It appears fine with only light calcium deposits inside the hose fittings and perfect impedance. However, the circulating pump, when spun with a shop vac on one hose fitting, shakes like a leaf and the impeller looks like it's bouncing around like an out of balance washing machine.
Correct me on my diagnosis if I'm wrong, please, but I think the circulator is pumping water enough to keep from tripping the high limit but not enough to keep the pressure up so the pressure switch is popping. The pump gets worse as the water gets warmer, which is why I can heat a water change reasonably warm with no trouble but find it impossible to heat it the rest of the way.
Regardless, I'm fairly sure the circulator is toast even if it's not the reason my heater pressure switch is popping, so I went looking for a replacement for it (it's the Watkins SilentFlo 5000, looks like the Laing version). I found that the Laing SM-909-NH-14 in the 115v version appears to be the same pump, with 3/4 hose barb fittings (
http://www.laing.biz/norylsm909n14.htm). It shows 65 watts, .58 amps, exactly the same as the original "Watkins" pump, and the illustration looks exactly the same except it's red. The only difference is that any place I can find selling this pump lists it as a 1/50 horsepower pump, where the original "Watkins" pump shows 1/20 hp.
It is dancing around freezing temperatures here, so I followed the Watkins instructions exactly for winterizing until I can fix this, including using a shop vac reversed to force air into the filter ports and out of all of the jets. I do not hear water gurgling anywhere after performing this procedure.
So, some questions:
1. Is the SM-909-NH-14 115v version what I need, regardless of the stated horsepower difference (how could that be if the wattage is the same and it's the same design motor?!?!)?
2. Could a sluggish pump cause the pressure cut-out to pop under the circumstances I describe? Again, I am positive the filters are clean and flow well.
3. I have read that even if the plumbing is sucked out with a shop vac there is still some water in it and it will crack things, and that RV antifreeze should be used. I was meticulous about following the manufacturer's procedure and do not hear water gurgling. Do I need to use the RV antifreeze anyway? I will be fixing this in the next few days but do not want freezing temperatures to break anything further.
Thanks for reading if anyone actually got through this novel, I very much appreciate opinions!
