Sundance Capri spa OH but water not that hot

[wpatters1229]

I got that OH error. Removed the filter and no change. The pump is working just fine and strong as normal. Temp is showing 118 degrees and fluctuating down to 109, 111 etc. but the water is not hot...maybe 85 or 90 as I can easily feel it with my hand and it is not nearly that hot.
This is a 2005 unit and has always worked fine. I have had to replace a flow switch and once a temp sensor but nothing serious.
Could this be that the heater is going out?
What is the procedure for checking the heater?
I have also read that resetting the board by moving the jumper can clear these problems.
We did stop using the spa for a few months while we had a heatwave here in CA. Could that have caused it to feel unwanted?

 

[cowboycasey]

Welcome to TFP

From the sound of it your temp sensor has broke again, if it is reading that hot and the temp is 90 then it is bad or not working correctly at least.. can you try to reseat the temp sensor and see if that fixes it and also reset the board if not order a new sensor and replace...

 

[wpatters1229]

Sounds like you read my mind. Tomorrow I will do a reset and then make sure the temp sensor is all OK. I did add a resistor a year ago to one of the lines going to the sensor so I could get past 104 F. I like it about 106. I do not think that should affect the sensor.
I did order one though just in case none of those things work.
I was told once that if the filter bangs into the sensor it can get damaged. Maybe that happened...