Common problems guide

The most common Biasi boiler problems

The faults we see most often across the Biasi range — with plain-English causes, what to check first, estimated repair costs, and whether it's a DIY job or needs a Gas Safe engineer. Based on fault-code data across 28 Biasi boiler models.

268 unique codes
28 models covered
8 DIY-safe (top 8)
8 engineer needed

The most common Biasi faults

01
E01 High DIY-safe

Your boiler has failed to light the gas flame and has locked itself out for safety.

What to try first

Check that your gas supply is turned on and other gas appliances are working.Press and hold the Reset button for 2 seconds then release.Wait for the boiler to attempt to restart; repeat up to three times if it fails.

Est. cost
£100-£250
Parts
Ignition Electrode, Gas Valve, Printed Circuit Board (PCB)
Full guide for Riva Advance M96.24SM E01
02
Lock-out High DIY-safe

Your boiler has switched itself off because it has detected that the water inside has become dangerously hot.

What to try first

Check that all radiator valves are fully open to allow water to flow.Ensure there is enough water pressure in the system by checking the pressure gauge.Wait for the boiler to cool down and press the reset button on the control panel.

Est. cost
£100-280
Parts
Circulation Pump, Overheat Thermostat, Primary Heat Exchanger
Full guide for Riva Advance M96.24SM Lock-out
03
Lock-out state High DIY-safe

Your boiler has attempted to light itself four times without success and has turned itself off for safety.

What to try first

Check if other gas appliances in your home, like a cooker, are working to confirm gas supply.Ensure your gas meter has credit and the emergency control valve is open.Press the reset button on the front control panel once to attempt a restart.

Est. cost
£100-350
Parts
Ignition Electrode, Gas Valve, Ignition PCB
Full guide for Riva Advance M96.24SM Lock-out state
04
ER + 69 High DIY-safe

Your boiler has detected an electrical configuration error and cannot operate safely, meaning you will have no heating or hot water until it is reset or repaired.

What to try first

Locate the selector switch on the front control panelTurn the dial to the 'R' (Reset) position for five secondsTurn the dial back to the 'On' position and wait for the boiler to restart

Est. cost
£100-280
Parts
Main Printed Circuit Board (PCB), External Interface Connection
Full guide for Parva 24S ER + 69
05
LP High DIY-safe

Your boiler has detected that the water pressure is too low to operate safely.

What to try first

Locate the filling loop valves underneath the boiler.Slowly open both taps to let fresh water into the system.Close the taps once the pressure gauge on the front of the boiler reaches between 1 and 1.5 bar.

Est. cost
£0-120
Parts
Filling loop hose, Water pressure switch, Expansion vessel
Full guide for Riva Advance M96.28SM LP
06
Lack of burner ignition High DIY-safe

Your boiler is failing to light the gas flame required to heat your water and home.

What to try first

Check that your gas supply is turned on and other gas appliances are workingCheck if your prepaid gas meter has sufficient creditPress and hold the reset button for five seconds

Est. cost
£120-350
Parts
Ignition Electrode, Gas Valve, Printed Circuit Board (PCB)
Full guide for Riva Plus M296.24SM Lack of burner ignition
07
Safety thermostat lock out High DIY-safe

Your boiler has overheated, causing it to shut down automatically for safety.

What to try first

Check that all radiator valves are open to ensure water can flow properly.Wait for the boiler to cool down for at least 20 minutes.Rotate the selector switch to the reset position 'R' for a few seconds and then back to the desired setting.

Est. cost
£100-250
Parts
Overheat Thermostat, Circulation Pump, Primary Heat Exchanger
Full guide for Riva Plus M296.24SM Safety thermostat lock out
08
Flame detection error High DIY-safe

Your boiler has failed to light or cannot detect a flame, meaning it will not provide heating or hot water until the issue is resolved.

What to try first

Check if your gas supply is active by testing another gas appliance like a hob.Try resetting the boiler by turning the control knob to the 'R' position for a few seconds.Ensure there is no frozen condensate pipe or blocked flue terminal outside.

Est. cost
£100-280
Parts
Ignition Electrode, Gas Valve, Flame Sensing Electrode
Full guide for Riva Plus M296.24SM Flame detection error

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