BoilerFaultCodesPotterton Condensate Pump (Green Light) Fault Code
Also written as CONDENSATEPUMPGREENLIGHT — same fault.
The Potterton Condensate Pump (Green Light) fault code means: your boiler is currently pumping away waste water, which is a normal part of its operation and doesn't necessarily mean there is a fault.. It appears on 1 Potterton model in our database.
Technical description: This indicates that the Condensate Pump is running. The pump ONLY runs when the condensate reservoir is full.
What causes the Potterton Condensate Pump (Green Light) fault?
This occurs when the internal collection tank becomes full of waste water produced during the heating process. The pump is physically triggered to move this liquid away from the boiler and into a drain. It is a sign that the mechanical float or sensor has reached its limit and is working exactly as intended to prevent an overflow.
This is more common during very cold spells, as external drain pipes can freeze, causing the pump to run more frequently or struggle to clear the water.
DIY fix possible
Observe the light for a few minutes; it should turn off once the water has been drained.If the light stays on indefinitely, check the external white plastic pipe for blockages or ice.Ensure the pump's discharge hose isn't kinked or restricted.
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Gas Safe Register →Potterton models that show the Condensate Pump (Green Light) fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Potterton Condensate Pump (Green Light) fault code information on this page is sourced and cross-checked against the official Potterton service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026