Medium
E.02.47 on Baxi 800 System 2

Your boiler has lost its connection to an external control, such as your room thermostat or smart hub, meaning it cannot receive instructions on when to turn the heating on.

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

Connection to external device unsuccessful

From this model's manual
Verified against the Baxi/Baxi 818 System 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

E.02.46View →E.02.48View →

All 75 fault codes on the 800 System 2

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

254A.00.34A.02.06A.02.18A.02.36A.02.37A.02.45A.02.46A.02.48A.02.49A.02.54A.02.55A.02.76E.00 .04E.00 .05E.00 .06E.00 .07E.00 .16E.00 .17E.00.20E.00.21E.01.04E.01.12E.01.17E.01.20E.02.13E.02.15E.02.17E.02.35E.04.00E.04.01E.04.02E.04.03E.04.07E.04.08E.04.09E.04.10E.04.11E.04.12E.04.13E.04.14E.04.15E.04.17E.04.18E.04.19E.04.20E.04.21E.04.23E.04.24E.04.54H.00.42H.01 .00H.01 .05H.01 .08H.01 .14H.01 .18H.01 .21H.02 .00H.02 .02H.02 .03H.02 .04H.02 .05H.02 .07H.02 .09H.02 .10H.02 .12H.02 .38H.02 .70H.03 .00H.03 .01H.03 .02H.03 .05H.03 .17H.03 .54

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