BoilerFaultCodesHeatline 0.8bar Fault Code
Also written as 08BAR — same fault.
The Heatline 0.8bar fault code means: your boiler has detected that the water pressure is too low for it to operate safely and effectively.. It appears on 1 Heatline model in our database.
Technical description: LCD display will flash should the pressure drop below 0.8bar
DIY fix possible
Locate the filling loop (usually a silver flexible hose) underneath the boiler.Slowly open the one or two taps/valves until you hear water entering the system.Watch the pressure gauge and close the taps 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 →Avoid the next call-out bill
A cover plan would handle faults like 0.8bar: no call-out fees, no surprise bills.
Affiliate links. We may earn a commission at no extra cost to you.
Heatline models that show the 0.8bar fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Heatline 0.8bar fault code information on this page is sourced and cross-checked against the official Heatline service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026