Medium
S.33 on Glow-worm Essential

Your boiler is currently holding its internal fan on as a safety precaution while it waits for the water pressure to reach the correct level.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Forcedfanoperationuntilthepressuremonitorisswitched

From this model's manual
Verified against the Glow Worm Essential installation & service manual, page 34.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check the pressure gauge on the front of the boiler.If the needle is below 1 bar, locate the filling loop (usually a silver braided hose under the boiler).Open the valves on the filling loop to allow water into the system until the gauge reaches 1.5 bar.Close the valves tightly and restart the boiler.

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