Biasi Inovia 25C ERP Fault codes & diagnostics

27 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.

Combi Natural Gas 2015-present
GC Number 47-583-38
Download the Biasi Inovia 25C ERP manualThe official installation and service manual (PDF), the document these fault codes were read from. PDF

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Severity at a glance

Each cell = one fault code. Hover to identify.
24 High 3 Medium
Fault codes

All 27 documented codes

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An 11

Your boiler is struggling to light its burner or cannot detect that a flame has been successfully lit, preventing it from heating your water.

High DIY-safe £90-280

What to check first

  1. Check if other gas appliances, like your hob, are working to ensure gas is reaching the property.
  2. Verify that your prepaid gas meter has credit if applicable.
  3. Press and hold the 'Reset' button for five seconds to see if the boiler restarts.

Parts commonly replaced

  • Ignition Electrode
  • Flame Sensing Probe
  • Gas Valve

Related codes

Full explanation for An 11
E01

Your boiler has temporarily stopped working because it failed to ignite safely.

High DIY-safe £90-250

What to check first

  1. Check if your gas supply is working by testing another gas appliance like a hob.
  2. Check your gas prepayment meter to ensure you have credit.
  3. Locate the reset button on your boiler, press and hold it for 5 seconds, and release to see if it restarts.

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Printed Circuit Board (PCB)

Related codes

Full explanation for E01
E02

Your boiler has temporarily stopped working as a safety precaution due to an internal lock-out, meaning you currently have no heating or hot water.

High DIY-safe £90-250

What to check first

  1. Locate the reset button or turn the mode selector to the reset position on your Biasi boiler.
  2. Hold or turn the reset control for 2 to 5 seconds to clear the lock-out.
  3. Wait to see if the boiler fires up normally; if the code returns immediately, do not keep resetting it.

Parts commonly replaced

  • Printed Circuit Board (PCB)
  • Ignition Electrode
  • Gas Valve

Related codes

Full explanation for E02
E03

Your boiler has safely shut itself down because it cannot detect a proper flame or exhaust the waste gases correctly.

High Engineer only £100-£250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Printed circuit board (PCB)

Related codes

Full explanation for E03
E04

Your boiler has temporarily stopped working for safety reasons, usually because it cannot detect a flame or has lost water pressure.

High Engineer only £100-£250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • PCB

Related codes

Full explanation for E04
E05

Your boiler has safety-locked itself because it is having trouble detecting or maintaining a flame.

High DIY-safe £100-£250

What to check first

  1. Check that your gas pre-payment meter has credit (if applicable)
  2. Check that other gas appliances in your home, like a hob, are working correctly
  3. Press and hold the 'Reset' button for five seconds to attempt to restart the boiler

Parts commonly replaced

  • Ignition electrode
  • Flame sensing electrode
  • Gas valve

Related codes

Full explanation for E05
E06

Your boiler has safely shut itself down due to a general internal error and requires a manual reset or professional attention to get running again.

High DIY-safe £90-200

What to check first

  1. Check the system pressure gauge is between 1 and 1.5 bar.
  2. Locate the reset button or turn the mode selector to the reset position.
  3. Hold the reset button for 2-5 seconds to clear the lockout.

Parts commonly replaced

  • Printed Circuit Board (PCB)
  • Ignition Electrode
  • Gas Valve

Related codes

Full explanation for E06
E07

Your boiler has safely locked itself out and stopped working because it has detected a safety or operational fault that needs attention.

High Engineer only £150-350

Parts commonly replaced

  • Printed Circuit Board (PCB)
  • Flame sensor electrode
  • Gas valve

Related codes

Full explanation for E07
E08

Your boiler has temporarily shut itself down for safety because it has detected a recurring operational issue.

High Engineer only £100-250

Parts commonly replaced

  • Gas valve
  • Main printed circuit board
  • Ignition electrode

Related codes

Full explanation for E08
E09

Your boiler has safely shut itself down due to an internal safety lock-out that requires professional attention.

High Engineer only £100-250

Parts commonly replaced

  • Printed Circuit Board (PCB)
  • Gas Valve
  • Ignition Electrode

Related codes

Full explanation for E09
Showing 11–20 of 27
E10

Your boiler has shut down because a sensor detected that the exhaust gases are becoming too hot, which is a safety measure to prevent damage to the internal components.

High Engineer only £120-280

Parts commonly replaced

  • Flue NTC sensor
  • Main heat exchanger
  • Printed Circuit Board (PCB)

Related codes

Full explanation for E10
E12

Your boiler has safely shut itself down due to a general safety lock-out, meaning it has stopped working until the underlying issue is cleared.

High Engineer only £100-250

Parts commonly replaced

  • Printed Circuit Board (PCB)
  • Ignition Electrode
  • Gas Valve

Related codes

Full explanation for E12
E13

Your boiler has completely stopped working and locked itself out for safety reasons due to an internal fault.

High Engineer only £150-300

Parts commonly replaced

  • PCB
  • Gas Valve
  • Ignition Lead

Related codes

Full explanation for E13
E14

Your boiler has temporarily stopped working and locked itself out as a safety precaution due to an internal fault.

High Engineer only £150-300

Parts commonly replaced

  • Main PCB
  • NTC Sensor
  • Ignition Electrode

Related codes

Full explanation for E14
E19

Your boiler is having trouble measuring the temperature of the cold water coming in, which may affect how well it heats your hot water.

Medium Engineer only £90-160

Parts commonly replaced

  • DHW Inlet NTC Thermistor
  • Wiring Harness

Related codes

Full explanation for E19
E20

Your boiler has stopped working because it cannot safely detect or ignite a flame, resulting in a total lockout for safety reasons.

High Engineer only £180-350

Parts commonly replaced

  • Gas Valve
  • Ignition Electrode
  • Printed Circuit Board (PCB)

Related codes

Full explanation for E20
E21

Your boiler has stopped working because it failed to ignite or check the gas flow properly for safety reasons.

High Engineer only £180-450

Parts commonly replaced

  • Gas Valve
  • Ignition Electrode
  • Printed Circuit Board (PCB)

Related codes

Full explanation for E21
E22

Your boiler has detected an issue with the gas valve or the electrical supply to it, preventing the burner from igniting to keep your home warm.

High Engineer only £150-300

Parts commonly replaced

  • Gas valve
  • Wiring harness
  • PCB

Related codes

Full explanation for E22
E23

Your boiler has stopped working because it cannot safely ignite the gas or maintain a flame.

High Engineer only £150-£350

Parts commonly replaced

  • Gas Valve
  • Ignition Electrode
  • Printed Circuit Board (PCB)

Related codes

Full explanation for E23
E24

Your boiler has failed to light the flame safely, so it has locked itself out to prevent gas from escaping.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Printed Circuit Board (PCB)

Related codes

Full explanation for E24
Showing 21–27 of 27
E25

Your boiler has temporarily stopped working for safety reasons and needs to be reset.

High DIY-safe £90-200

What to check first

  1. Locate the reset button or turn the mode selector to the reset position on your boiler's control panel.
  2. Hold the reset button for 2 to 5 seconds and release it.
  3. Wait a moment to see if the boiler fires up and resumes normal operation.

Parts commonly replaced

  • Ignition Electrode
  • Gas Valve
  • Printed Circuit Board (PCB)

Related codes

Full explanation for E25
E50

Your boiler has lost its connection to the thermostat or controller that manages the second heating zone in your home.

Medium DIY-safe £60-180

What to check first

  1. Check if the batteries in your Zone 2 room thermostat need replacing
  2. Ensure the remote control or thermostat is within range of the boiler
  3. Check for any wireless interference from other electronic devices near the receiver

Parts commonly replaced

  • Batteries
  • Wireless Receiver
  • Zone 2 Thermostat
Full explanation for E50
E69

Your boiler has stopped working because it has detected a problem with its internal electrical connections or wiring.

High Engineer only £90-250

Parts commonly replaced

  • Main PCB
  • Wiring Harness
  • Ignition Transformer

Related codes

Full explanation for E69
E98

Your boiler is having trouble communicating with the solar panel control system, which means your renewable energy setup isn't working correctly with your heating.

Medium Engineer only £150-£350

Parts commonly replaced

  • Solar control module
  • Printed Circuit Board (PCB)
  • Communication wiring

Related codes

Full explanation for E98
E99

Your boiler's internal computer has lost its settings and doesn't know which model it is supposed to be operating as.

High Engineer only £80-160

Parts commonly replaced

  • Main Printed Circuit Board (PCB)
  • External Software Key

Related codes

Full explanation for E99
Er10

Your boiler has safely shut down and locked itself to prevent potential risks, meaning you currently have no heating or hot water.

High Engineer only £150-300

Parts commonly replaced

  • PCB
  • Gas valve
  • Ignition electrode

Related codes

Full explanation for Er10
L 01

Your boiler has shut down because it is getting too hot while trying to provide hot water.

High DIY-safe £120-£350

What to check first

  1. Check that your boiler pressure is between 1.0 and 1.5 bar on the gauge
  2. Ensure all isolation valves under the boiler are fully open
  3. Turn the boiler power off and back on again to reset the system

Parts commonly replaced

  • DHW Plate Heat Exchanger
  • Temperature NTC Sensor
  • Diverter Valve

Related codes

Full explanation for L 01
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