BoilerFaultCodesYour boiler has stopped working because the pipe that carries waste water away is likely blocked or frozen, causing water to back up inside the unit.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Problem with condense trap/pipe/ sensor. Call engineer.
What causes this fault?
This fault occurs when waste water produced during the heating process cannot drain away from the boiler, causing it to back up inside the internal trap. The system detects this rising water level via a sensor and shuts down the boiler to prevent internal flooding or damage. The most common reasons are a blockage in the internal trap or an obstruction in the external pipework leading to a drain.
This fault is significantly more frequent during freezing winter temperatures, as the external waste pipe can freeze solid and prevent water from leaving the system.
DIY fix possible
Check the white plastic pipe outside for ice and pour warm (not boiling) water over it to melt any blockages.Ensure the end of the external pipe is not submerged in a drain or blocked by debris.Restart the boiler using the reset button once the pipe is clear.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like d1 & d2 — no call-out fees, no surprises.
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Vokera Synergy E is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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