Jandy JXI400N Not working

[fsworld]

Hello,

I have a Jandy JXI400N thats about 7 years old, its been working fine until the past month. It had an ignition fault but before I could start troubleshooting it, it went way and everything worked fine for a few weeks. Now I have a high water temp fault and the water temp is showing 145-150 which is clearly not the case.

I assume I need the temperature sensor replaced (Jandy JXi/LXi Temperature Sensor Kit | R0456500) but is there anything else to try or is that likely the issue? I guess what worries me a little is the ignition fault prior to this but maybe it was related to the temp? I didn't think to look at the temperature reading on the heater until I saw the fault. I guess I just assumed it used the temp from my Jandy panel.

Or could it be the high limit temperature sensors (Jandy JXi High Limit Temperature Sensors Kit | R0592300)? I assume that it would not be these since its reading high on the display.

Thanks,
Zach

 

[ajw22]

High water temperatures in the heater is usually due to low water flow. Before you suspect a bad sensor you should think the sensor is doing its job and the high water temperature is real.

When did you last clean your filter?

What is your clean filter PSI and current PSI?

What speed is the pump running at?

 

[fsworld]

High water temperatures in the heater is usually due to low water flow. Before you suspect a bad sensor you should think the sensor is doing its job and the high water temperature is real.

When did you last clean your filter?

What is your clean filter PSI and current PSI?

What speed is the pump running at?

Thanks for the reply. Its always showing the high temp even after turning the entire system off for a few hours and back on. It doesn't seem to change over time either. Water is coming out of the return so I know flow is there.

Filter was actually replaced a few weeks ago by me.

Its currently reading about 12PSI. I have always cleaned it when it reached 15PSI.

Normal pump speed is 1,750, when the heater is being used it goes to 2,250.

 

[ajw22]

Check the resistance of the temperature sensor with a multimeter. Read Temperature Sensors - Further Reading

 

[fsworld]

With the temperature sensor removed from the plumbing and disconnected its reading 1712ohms so thats close to the temp it was reading. With nothing connected the heater is reading -42 I believe.

 

[ajw22]

With the temperature sensor removed from the plumbing and disconnected its reading 1712ohms so thats close to the temp it was reading. With nothing connected the heater is reading -42 I believe.

Replace that sensor.

 

[fsworld]

New sensor is installed and everything is working, thanks for the help!