How much does it cost to fix Atag error code C1 33?

Typical repair cost for the Atag C1 33 fault is £150-300 including labour.

C1 33 High

Atag C1 33 Fault Code

Q: What does the Atag C1 33 fault code mean?

Your boiler is failing to light the fuel inside because it cannot detect a flame, causing the system to stop trying for safety reasons.

Also written as C133 — same fault.

The Atag C1 33 fault code means: your boiler is failing to light the fuel inside because it cannot detect a flame, causing the system to stop trying for safety reasons.. It appears on 4 Atag models in our database.

Technical description: No flame after 5 ignition attempts

Typical repair cost £150-300 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Atag models that show the C1 33 fault code

Click a model for the full fault code list and model-specific repair notes.

A200 Repair: £150-350
Q 25CR Repair: £120-250
S 25CR Repair: £150-300
Sov. Repair: £120-350

Source

Atag C1 33 fault code information on this page is sourced and cross-checked against the official Atag service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026