Baxi Pressure Gauge (below 0.5 bar) Fault Code
Also written as PRESSUREGAUGEBELOW05BAR — same fault.
The Baxi Pressure Gauge (below 0.5 bar) fault code means: your boiler has stopped working because the water pressure is too low, often caused by a small leak or recently bled radiators.. It appears on 5 Baxi models in our database.
Technical description: The boiler will not function. May indicate a leak on the central heating system.
DIY fix possible
Locate the external filling loop, which is usually a flexible silver hose with two small taps.Slowly open both taps to allow water into the system while watching the pressure gauge.Close both taps tightly once the needle reaches between 1.0 and 1.5 bar.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Baxi models that show the Pressure Gauge (below 0.5 bar) fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Baxi Pressure Gauge (below 0.5 bar) fault code information on this page is sourced and cross-checked against the official Baxi service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026