Medium
b 52 on Potterton Powermax HE 85 Litre

Your boiler is picking up an unusual reading from the hot water storage cylinder temperature sensor.

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

¡C Indicative cylinder temperature

From this model's manual
Verified against the Potterton/Potterton Powermax He 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

b 50View →b 51View →b 53View →

All 37 fault codes on the Powermax HE 85 Litre

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

0 00A 01A 02A 03A 04A 05A 07A 09-12A 15A 18A 19A 20A 33A 40A 41c 80E 01E 03E 04E 06E 07E 08E 13/16/19E 20E 21E 22E 29E 40E 41E 42P 0.1 - 0.4P 0.5 - 0.9P 1.0 - 2.9P 3.0 - 3.5t 80U 60

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