My service heater light keeps coming on and off. Occasionally the temp drops and heater won’t start until I turn on/off. What’s the issue? Recently you replaced pump to variable speed which lowers pressure. Does lower pressure affect the heater? Google seems to think so. I’m at work so if I don’t answe please call back or provide number I can call you so we can play telephone tag. Ha ha. Thanks.


  1. Nigel


    Hi Shaun. If the heater says service heater and you are able to get the service heater light to go away by power cycling the heater this is a low level safety switch trip. Water flow affecting the pressure switch is one scenario that could produce the service heater light. If the system 3 filters get soiled enough and the pump is on a lower rpm setting this could produce the service heater light. If the filters are soiled enough the light could also come on at a high rpm. Easy way to test it would be to remove the filters briefly to see if the heater fires ok at whatever rpm setting you have the pump set at. If all else fails contact our Service Support Desk to book a diagnostic and repair of your Maxetherm pool heater.

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