Heater min max nt powers up but will not call for heat

is ther power going to it if so check power supply or main power conversion board

Any error codes? Also underneath the touchpad there is a button you can push that will allow you to set the max temp. after you turn power on press button. the green pool light will light up, at this point using the arrows adjust your max temp. press button again to change to spa, press again to operate.

Your temp sensors are on the heater, a small tube that slides into the water manifold, usually on the left side. On the remote it will be in one of the pipes coming from the pump or the filter. If it is after the heater you should move it to between the filter and heater. It will be a tube that is in the pipe with a stanless steel clamp holding it in place.
To find out wich one it is you will need to remove the remote from the system by takeing the wires that go to it from the wireing inside the heater and wire nuting the wires in the heater together. If the heater runs normal then it is the sensor for the remote if not it is the sensor for the heater. Let me know how you do and if need be we can get a little more specfic for your system. good luck.

I have a similar problem with an Indesit oven. There are two thermostats one controlling the oven temperature which i think you have replaced and another over-temperature stat to prevent the oven getting to hot should the temp stat fail to control the temperature. The over- temperature stat could be operating to quickly and this cuts power to the the digital display, oven light, temp light and circulating fan. I am going to replace this over-temp stat

Your EO4 message tells you you have a fan problem. So ether your fan is diying wich you would hear or you have a bad presure sensor in your exaust. A new fan is a little pricey but the sensor is reasonable for heater parts. I can't be sure but I believe it ether screws onto or into your exaust and it just plugs on to your control board. If your sensor is going bad their is a reason and this should be addressed. It should be in your by-pass or your gas pressure. But as far as a new heater, not untill you have water coming from the cabnit. It is sometimes easer to sell new than keep up with new, Good luck let me know how you do.

replace valve assembly

You must turn on the pump and let water circulate through the pool and the heater before you turn on the heater otherwise you will ruin the heater

temp sensor get the new one with yellow wires.should do the trick.