This pcb board electrics is only for UK MODEL 220 = 240 volt The S100102 , some call it the square model pump. This has been tried and tested The part that regulates the temperature is making sure it gets to 40c. these S100102 don't show a error code when board goes wrong they just won't heat to top temperature. All other parameters are all order.. does it try to power up, and you can hear it making mas clicking noises , or just wont go above the 20,s in the heating cycle with no error code.. these 3 items i have found to have cured the problem in one go for buyers.. the red sensor on its own is for heating.. E05 the copper screw is a thermal reset E08 and the pcb board regulates the heat by a pwa
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