Medium
2 02 on Ariston Clas HE R

Your boiler is struggling to read the temperature of the water in your separate storage tank because the sensor responsible for checking it has a loose connection or a faulty reading.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Bottom storage temperature probe open / short circuit

Shared across the Clas HE range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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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All 45 fault codes on the Clas HE R

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

1 011 021 031 041 051 061 071 081 101 121 141 181 P11 P21 P32 042 072 083 013 023 033 043 053 063 074 075 015 025 045 P15 P25 P36 046 107 017 027 037 047 057 067 07116E00E99

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