Featured ARTESIAN ISLAND ELITE - HEATER TOO HOT/SENSOR B 114*

jeremycrook

Gold Supporter
Sep 26, 2016
169
OKLAHOMA CITY / OK
Like I mentioned I have a Artesian spa that is acting up, last year the heater core as well as the two temperature sensors were replaced as the heater was tripping the breaker. The temperature sensor is now getting too hot and shutting down the heating of the spa. The older sensor I had would work for a week or two, then start overheating. The new sensors I put in will only get up to temperature and then it gets too hot and the spa goes into protect mode. Does anyone know of another sensor to replace, or can help me get this fixed?
IMG_2451.jpegIMG_2450.jpeg
 

RDspaguy

In The Industry
Mar 21, 2020
1,077
Cabool, Mo
Post a pic of the heater, circuit board, and wiring diagram.
If it's set up like I suspect, then sensor b is at the heater output and you are having a low flow condition. Remove your filter(s) until we figure this out. It may start working just from that.
Does your tub have a 24 hour circulation pump? Is it getting good flow from the heat return jet?
 

jeremycrook

Gold Supporter
Sep 26, 2016
169
OKLAHOMA CITY / OK
Ahh, I think you are right on with the low flow. I had questioned this due to finding some white plastic in the flow lines after taking the heater core off. I didn't know what the stuff was, or where it came from. I doubt I have any left to determine what it is. I will take the side off and take some pics sometime, it's 18 degrees here and it's pretty tough to stay outside very long. I believe I have a pump that runs often, but I don't think 24 hour pump, as sometimes the water is calm? There are two jets down low in the tub that hot (or heated )water seems to come out of, one does have pretty good pressure and the other one has never had a heavy stream of water, just small thrust.
 

RDspaguy

In The Industry
Mar 21, 2020
1,077
Cabool, Mo
That's not plastic, it's scale. You need to drop your ph to around 7 for a week or two and dissolve/flake off that stuff. There might be some chemical to help with that. Maybe @JoyfulNoise knows of something or can offer some advice.
 

RDspaguy

In The Industry
Mar 21, 2020
1,077
Cabool, Mo
Yes. If you have flakes in your pipes they will build up at the heater and pump impeller, where they get caught, and create a partial blockage. That blockage causes the water to slow going through the heater which creates the higher temp at the output sensor. Also, scale buildup on sensors can insulate them and slow accurate readings. Sensor b tends to be quite close to the element and if the scale is heavy enough it can cause a direct connection between element and sensor which will overheat it even with good water flow.
 

jeremycrook

Gold Supporter
Sep 26, 2016
169
OKLAHOMA CITY / OK
Yes. If you have flakes in your pipes they will build up at the heater and pump impeller, where they get caught, and create a partial blockage. That blockage causes the water to slow going through the heater which creates the higher temp at the output sensor. Also, scale buildup on sensors can insulate them and slow accurate readings. Sensor b tends to be quite close to the element and if the scale is heavy enough it can cause a direct connection between element and sensor which will overheat it even with good water flow.
So, drop PH with MA for one to two weeks and drain & fill again? So just to be clear, I replaced the heater a year ago, that is when I found the scale. On another note, will ahhsome remove the scale, or just acid? I added 5 oz MA to the spa today, and dropped the PH to around 7 or lower. Do I add acid everyday, is it safe to float in the spa now, or keep out. TIA
 
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jeremycrook

Gold Supporter
Sep 26, 2016
169
OKLAHOMA CITY / OK
@RDspaguy I don't believe Ahhsome will combat scale. I think it's crud or buildup of oils, skin that it gets rid of. I am currently lowering the PH of the tub to <7 for two weeks with muriatic acid to hopefully get rid of anything that might be intruding on the pump, or sensors (I guess)? I just wanted to know if this is the only thing I should be doing at this time. The scale was found over a year ago, and am not sure if this is my only problem, hopefully it is. The tub has been shutting off every day (due to overheating) except for the last 4 days. I thought this (lowering PH) was working, until last night it shut off again. I guess I haven't uploaded pics of the wiring and board, I will do that later today. I just want this fixed, it's eating away at me...
 

RDspaguy

In The Industry
Mar 21, 2020
1,077
Cabool, Mo
It could definitely be something else, but it could be that as well. You are describing a flow restriction, and those can take many forms, from filters to broken parts to little black dresses sucked into a pump (yep, seen it). Where would you like to start? I am just following the clues.
 
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