BoilerFaultCodesThe 6 most common faults
Your boiler has become too hot and has shut down as a safety measure to prevent damage.
Check if your radiator valves are openBleed your radiators using a radiator key to remove trapped airOnce the boiler has cooled, press the reset button
Your boiler has detected that water is not moving through the system properly, which is causing it to overheat and shut down for safety.
Check that your system pressure is between 1 and 1.5 barEnsure all radiator valves and isolation valves are fully openGently bleed your radiators to remove any trapped air pockets
Your boiler is trying to light, but the burner isn't staying on or starting up as it should.
Check if your gas prepay meter has creditEnsure other gas appliances in the home are workingPress the Reset button once to see if the boiler restarts
Your boiler has detected that water isn't moving through the system correctly, which has caused it to shut down to prevent overheating.
Check that all radiator valves are fully openEnsure your external heating pump is running if accessibleGently bleed your radiators to remove any trapped airReset the boiler using the reset button
Your boiler has no electricity reaching it and the display has completely shut down.
Check if your home's main fuse box (consumer unit) has tripped a switch.Ensure the boiler's power switch or fused spur on the wall is turned on.Replace the 3-amp fuse in the boiler's external power plug or wall switch.
Your boiler has tried to start up but failed to light the flame, causing the system to shut down for safety.
Check that your gas emergency control valve is open and you have credit on your gas meter.Press the reset button once for five seconds to see if the boiler restarts.Ensure there are no external obstructions to the flue terminal outside.
on the Baxi Suprima 70
Based on parts cited in our fault code database. Your engineer will confirm what's actually needed after diagnosis.
Call a Gas Safe engineer if…
- You can smell gas or see signs of a leak
- The Baxi shows an Emergency or High severity code
- The boiler keeps locking out after repeated resets
- You've tried the DIY checks and the fault hasn't cleared
- There's visible water leaking from the boiler
- The flame is yellow or orange instead of blue