Emergency
33 on Ideal Maximiser SE 42

Your boiler has stopped working because the supply of gas reaching it is too low to operate safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Gas inlet-pressure too low; check the inlet-pressure during operation at maximum load. Inlet-pressure should amount to at least 20 mbar (25 mbar -17%).

From this model's manual
Verified against the Ideal/Ideal Maximiser Se 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 is a emergency 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

F33View →LCView →LFView →

All 40 fault codes on the Maximiser SE 42

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

- / A- / H- / Y= / H4 / A111213141516171819202122232425262728293031323435363738394041424344E / F

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