How much does it cost to fix Halstead error code Erroneous APS signal?

Typical repair cost for the Halstead Erroneous APS signal fault is £150-300 including labour.

Erroneous APS signal High

Halstead Erroneous APS signal Fault Code

Q: What does the Halstead Erroneous APS signal fault code mean?

Your boiler has stopped working because it cannot confirm that waste gases are being safely pushed out through the flue, which is a necessary safety step before it can fire up.

Also written as ERRONEOUSAPSSIGNAL — same fault.

The Halstead Erroneous APS signal fault code means: your boiler has stopped working because it cannot confirm that waste gases are being safely pushed out through the flue, which is a necessary safety step before it can fire up.. It appears on 4 Halstead models in our database.

Technical description: Missing or defective APS signal • Check APS • Check pipe connections for blockage • Check fan • Check PCB • Check flue condition

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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Halstead models that show the Erroneous APS signal fault code

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

Source

Halstead Erroneous APS signal fault code information on this page is sourced and cross-checked against the official Halstead service / installation manuals for each affected model.

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