# Thermistor sensor Reliance water heater



## JoeL92 (12 mo ago)

Hello,

I have a Reliance water heater Model # *12-50-EART 100* | Serial # *1650104274009*
This unit is 6 years old

This model Utilizes the Energy Smart Module (ESM) I have an error code *E 0 7 *(lower thermistor sensor failure). So, at the upper thermostat I have a two PIN connector with two black wires that run behind the insulation to the lower element where usually a lower thermostat would be its just the end of the two black wires attached to a black rubber which I assume is what they call the thermistor sensor. I've had no luck in finding this part. Can I bypass this entire system by installing a new upper thermostat and replacing the thermistor with a thermostat? 










Wiring Diagram












Error Code









Thermistor connector









Thermistor sensor


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## skoronesa (Oct 27, 2015)

Just bridge the connection with a 50ohm, 5watt power resistor. This will cause the unit to only use the lower thermostat.

Otherwise get a whole new heater.


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## Debo22 (Feb 15, 2015)

Probably has a flue blockage, get a new power vent motor


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## Sstratton6175 (Jan 10, 2021)

If the fuel/air mixture is incorrect it will burn out those thermistors every time.


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## OpenSights (Mar 23, 2015)

JoeL92 said:


> Hello,
> 
> I have a Reliance water heater Model # *12-50-EART 100* | Serial # *1650104274009*
> This unit is 6 years old
> ...


Your master and journeyman have failed you. I suggest you find a different plumbing company to work for. I’ve worked for some hack companies before too, so no judgment from my part.

The plumbing trade is something to stick with! Per forum rules, please post an intro with details about your professional involvement in the trade.


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## DDDave (Aug 6, 2014)

Where's all that wet rust coming from/going? Ever seen a flame when you open an element cover? Kind of smells.


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## sparky (Jan 8, 2014)

The flux capacitor has gone out and is definitely not fluxing properly


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## KCPlumb (Oct 26, 2021)

That thing is leaking. Replace it.


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