Low
2 05 on Ariston Clas One

Your boiler is having trouble reading the temperature of the water heated by your solar panels, likely due to a loose wire or a faulty sensor connection.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

D.H.W. In sensor open / short circuit (solar)

From this model's manual
Verified against the Ariston/Ariston Clas Net One installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

2 07View →

All 46 fault codes on the Clas One

Seeing a different code? Every code this model can display, in one place.

1 011 031 041 051 061 071 081 091 101 121 141 161 181 P11 P21 P31 P43 013 023 033 043 053 063 073 P94 114 124 135 015 025 045 P15 P25 P36 106 127 017 027 037 117 127 137 227 237 50

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