High Lockout
ERROR CODE 3 on Ideal Icos HE

Your boiler has detected an issue with the air pressure or water flow sensors, preventing it from firing up for safety.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

Technical description

WPS / PPS ALARM

What causes this fault?

This fault occurs when the boiler's internal sensors detect that either the water pressure is too low or the fan isn't moving air through the system correctly. For safety reasons, the boiler will refuse to ignite if it cannot confirm that water is flowing and harmful exhaust gases are being safely vented away. The most common reasons are a leak in the central heating system causing a drop in pressure, or a physical blockage in the air tubes or flue.

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

ERROR CODE 1View →ERROR CODE 2View →

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