20 Most Recent Sta Rite Sr200na - Max E Therm - Pool & Spa Heater - Dual Electronic Iginition Lo - Nox - 200,000 Btu - Natural Gas Questions & Answers

Temperature Thermistor is bad

With these particular pool heaters, troubleshooting without specifics is very difficult to do. The users manual actually has a flow chart that walks you through, step by step, questions that you will need to answer to determine the problem. That is going to be your best shot at finding a solution. Here is a link to a pdf version of the users manual.

http://www.backyardcitypools.com/images/bwp/Max-E-Therm-Manual.pdf

Please post your question on the Local Repair tab of FixYa.com or call your local pool supplier.

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do u have chlorine tablets on t skimmer?

I would like you to try a reset of the system. Turn off the power on the heater, then turn off the circuit breaker that goes with the heater. Wait about 20 minutes and then try and start the heater. If it still will not power up, turn the display panel over, there are diagnostic lights on the back side. If the light is on next to the AFS, that is the Air Flow Switch.

I am not sure if you have solved this issue, or not, but just in case. The problem is the Thermister, or temp sensor. That will need to be replaced since it is reading the water temp at 125.

The Thermister is located on the manifold, left hand side, between the first two bolts. It is pretty easy to change out and this will correct the problem.

this is typical of a dirty flame sensor.your model does not have a thermo couple.remove sesor and clean with steel wool or fine emory cloth

https://www.youtube.com/watch?v=V45_D0l2s5A https://www.youtube.com/watch?v=e8RMfw4nZos https://www.troublefreepool.com/threads/max-e-therm-400-service-system-light-on.52433/

Check the control wire that might be connected to the control fuse. If that wire is open the unit will only cycle thru the board information and the sit dormant until the control is called for.

Try changing the Thermal Regulator. You could just remove the T/R as a test and replace as necessary.

replace the mechanical shaft seal. check impeller and diffuser for damage . prime pump after any repair