Main 25 eco combi boiler E 50 fault code ! Help plz

[d.o.n.]

Hi-a bit of help plz-i have a main combi boiler 25 eco that is coming up with E 50 fault code.

Central heating is working but no sign of hot water-when hot tap is on there is no call for hot water on the led lights,I've tried resetting the boiler and also switching it off at the mains also to no avail.
Is this more than likely the thermistor-i know it can be tested on ohms or may it be the flow turbine.....any help much appreciated.

The e50 lights flashes constantly.

 

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"Why is main combi boiler 25 eco coming up with E 50 fault code?"

It's a Negative Temperature Coefficient sensor fault apparently. This helps regulate water temperature by sending readings to the boiler’s control board.

 

[Agile]

You should check the resistance of the sensor. Probably a nominal 10k at room temperature. Also check that its plug is making properly.

A common fault is that they can go open circuit.

If you wanted to check that the boiler PCB is properly reading the sensor put a 10k resistor across the sensor terminals and see if the E 50 code disapears.

 

[d.o.n.]

Thanks for the replys-if I buy a new ntc sensor and just plug it in dangling without actually fitting it the actual boiler should that get rid of the e 50 fault or does it actually need to be physically screwed in.

Thx

 

[CountryFan]

I think the boiler requires resetting, can't remember off hand. NTC could also be a wet pocket type and you may need to carry out safety checks afterwards (26.9)