<!-- from fixya rte -->My Davey xs250 doesn't seem to be heating up - Pool & Spa

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replace the pressure control switch as the problem indicates the non-return valve is leaking back and not holding pressure

turn up heat if it doesnt go check temp if it seems odd replace temp sensor ohm it out if 78 ohms at 70 degrees its ok then check heater element fuses and element

Replce the coils. if this fails you will need a new CDI. both are common problems with the Yamaha XS250 Whichever model you have.

since neither light is going on, then i believe that you either have a bad thermostat, or possibly that you only have half of the voltage going to it, and gaggenau doesn't have gas units so it doesn't have a glow bar like the previous guy said.

It neds to be where there is at least a little slack in the cable at the lever. Or else it will not be fully engaging.