Biasi Basica Cond 24C M275V.2024 SM Fault codes & diagnostics

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

Combi Natural Gas
GC Number 47-583-49
Download the Biasi Basica Cond 24C M275V.2024 SM 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.
22 High
Fault codes

All 22 documented codes

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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
E10

Your boiler has safely shut itself down because it has detected a safety lockout, meaning it will not produce heat or hot water until the issue is cleared.

High DIY-safe £90-250

What to check first

  1. Check your gas supply by testing another gas appliance like a cooker.
  2. Inspect the condensate pipe outside to ensure it is not frozen or blocked.
  3. Locate the reset button or turn the mode dial to reset, and hold it for a few seconds to see if the boiler restarts.

Parts commonly replaced

  • Gas Valve
  • Ignition Electrode
  • Printed Circuit Board

Related codes

Full explanation for E10
Showing 11–20 of 22
E11

Your boiler has safely locked itself out to prevent a potential hazard, meaning you currently have no heating or hot water.

High Engineer only £150-350

Parts commonly replaced

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

Related codes

Full explanation for E11
E12

Your boiler has detected a problem with the internal sensor that monitors the temperature of the water returning to the unit, which is preventing it from running safely.

High Engineer only £90-160

Parts commonly replaced

  • Return NTC thermistor
  • Connecting wiring harness

Related codes

Full explanation for E12
E13

Your boiler has detected that there is too much water pressure in the central heating system.

High DIY-safe £80-160

What to check first

  1. Check that the internal or external filling loop valves are tightly closed.
  2. Bleed water from a radiator using a radiator key to lower the pressure.
  3. Monitor the pressure gauge on the boiler until it sits between 1 and 1.5 bar.

Parts commonly replaced

  • Filling loop valve
  • Expansion vessel
  • Pressure relief valve (PRV)

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
E22

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

High Engineer only £100-£250

Parts commonly replaced

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

Related codes

Full explanation for E22
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
E26

Your boiler has temporarily stopped working and locked itself out for safety, meaning you currently have no heating or hot water.

High Engineer only £100-250

Parts commonly replaced

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

Related codes

Full explanation for E26
E28

Your boiler has safely shut itself down due to a safety lock-out, meaning it needs to be manually reset or inspected by a professional.

High Engineer only £100-250

Parts commonly replaced

  • PCB
  • Ignition Electrode
  • Gas Valve

Related codes

Full explanation for E28
E50

Your boiler has temporarily stopped working and locked itself for safety due to a general fault it has detected.

High Engineer only £100-250

Parts commonly replaced

  • Main control board
  • Ignition electrode
  • Gas valve

Related codes

Full explanation for E50
E52

Your boiler has safely shut itself down due to a safety lock-out, meaning it has temporarily stopped working to prevent potential issues.

High Engineer only £150-350

Parts commonly replaced

  • Gas valve
  • Main PCB
  • Ignition electrode

Related codes

Full explanation for E52
Showing 21–22 of 22
E54

Your boiler has completely stopped working and locked itself out for safety due to a persistent operational fault.

High Engineer only £150-350

Parts commonly replaced

  • Printed Circuit Board
  • Gas Valve
  • Electrodes

Related codes

Full explanation for E54
E58

Your boiler has safely shut itself down due to a safety lock-out, meaning it needs to be manually reset or checked by a professional.

High Engineer only £100-250

Parts commonly replaced

  • PCB
  • Ignition electrode
  • Gas valve

Related codes

Full explanation for E58
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