Vaillant Thermistors
The thermistor decreases circuit resistance as the temperature of the thermistor rises. The electronic control board sends a current to the thermistor and can tell whether an increase or decrease in heat is needed by the resistance provided by the thermistor.
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Vaillant 193592 Negative Temperature Coefficient Sensor - ecoTEC/ecoTEC Plus/VU
Part No: 1375070 / MPN: 193592
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Vaillant 178988 Flow Sensor - Black - ecoTEC Exclusive VUW/ecoTEC Plus VUW
Part No: 1376548 / MPN: 178988
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Vaillant 103430 NTC Sensor - DHW Heat Exchanger - ecoTEC Pro VUW/ecoTEC Plus R1
Part No: 1375316 / MPN: 103430
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Vaillant 103429 NTC Sensor - DHW Outlet Pipe - ecoTEC Plus/VUW/ecoTEC Exclusive
Part No: 1375314 / MPN: 103429