High
50-70 (ll-ll) on Ariston Clas HE 35

Your boiler is currently unable to provide hot water because it is having trouble reading the temperature of the water coming from your taps.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

D.H.W.thermistor faulty (short circuit)

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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