High
E133 on Main Eco Compact Combi

Your boiler has failed to light because it is not receiving enough gas or cannot detect the flame used to heat your water.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Interruption of gas supply or flame error

From this model's manual
Verified against the Main/Main Eco Compact 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.

What causes this fault?

This fault occurs when your boiler tries to light itself several times but fails to establish or maintain a steady flame. The most common reason is a shortage of gas reaching the burner, often caused by an external supply issue or a blockage in the internal components. It can also happen if the sensor that monitors the flame is dirty or damaged, preventing the boiler from knowing it has successfully fired up.

This fault is much more common during freezing winter temperatures, as the external condensate pipe can freeze and back up, preventing the boiler from lighting.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

All 71 fault codes on the Eco Compact Combi

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

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