Unknown
e[03 on Main MainEco

Main MainEco fault code e[03

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

Sensor fault, temperature fault or flow fault

From this model's manual
Verified against the Main/Main Maineco Combi 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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All 61 fault codes on the MainEco

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

5v[05v[15v[25v[75v[105v[115v[125v[135v[155v[165v[175v[185v[195v[205v[215v[225v[25Code ACode BCode CCommunication faulte[00e[01e[02e[04e[05e[06e[07e[08e[09e10e11e12e14e16e17e34e35e36e37e38e39e40e41Error code 1Error code 2Error code 3Error code 4Error code 5Error code 6Fan faultFlame lossIgnition faultMiscellaneousOverheat temperature protectionParameter errorReinitialisationResetting...Sensor errorTemperature protection

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