Baxi 613 Heat Fault codes & diagnostics

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

Regular Natural Gas 13 kW 2017-present
GC Numbers 41-470-5141-470-5241-470-5341-470-6641-470-6741-470-6841-470-6941-470-7041-470-7741-470-7841-470-79
Download the Baxi 613 Heat manual The official installation & service manual (PDF) — the exact document these fault codes were verified against. PDF

This boiler uses LED flash patterns

Count the flashes in one repeating group before the pause. That number is your fault code. Do not reset until you have noted it. How to read fault codes →

Severity at a glance

Each cell = one fault code. Hover to identify.
13 High 1 Low
Versions & GC numbers

Which version do you have?

The GC number on your boiler's data badge identifies the exact appliance and production years, as recorded in the UK Product Characteristics Database.

GC number Appliance (register name) Produced
41-470-51 HEAT 415 2017–present
41-470-52 HEAT 418 2017–present
41-470-53 HEAT 424 2017–present
41-470-66 613 HEAT 2020–present
41-470-67 616 HEAT 2020–present
41-470-68 619 HEAT 2020–present
41-470-69 625 HEAT 2020–present
41-470-70 630 HEAT 2020–present
41-470-77 816 HEAT 2020–present
41-470-78 825 HEAT 2020–present
41-470-79 830 HEAT 2020–present
Just want the most common Baxi 613 Heat faults?
The top 6 problems in plain English — with causes, DIY checks and repair costs.
Fault codes

All 14 documented codes

Tap any card for details

LED / flash-pattern codes
1 flash green

Your boiler has shut down because it is getting too hot too quickly, usually due to a lack of water flow through the system.

High DIY-safe £100-280

What to check first

  1. Check that your home's central heating valves and radiator valves are fully open.
  2. Ensure the system pressure is between 1 and 1.5 bar on the pressure gauge.
  3. Check if the condensate pipe (the white plastic pipe outside) is frozen or blocked.

Parts commonly replaced

  • Circulating Pump
  • Heat Exchanger
  • Flow/Return Thermistors

Related codes

Full explanation for 1 flash green
1 flash red

Your boiler has stopped working because it cannot correctly detect the water temperature or the water isn't moving through the system as it should.

High DIY-safe £90-220

What to check first

  1. Check that all radiator valves and isolation valves are fully open
  2. Check that your external pump (if visible) is running and hasn't seized
  3. Reset the boiler by turning the selector knob to 'R' for five seconds and then back to 'On'

Parts commonly replaced

  • Flow temperature sensor (NTC thermistor)
  • Return temperature sensor
  • External central heating pump
Full explanation for 1 flash red
2 flashes green

Your boiler has shut down because a safety or external control circuit, such as an energy-saving thermostat or an external sensor, has been disconnected or interrupted.

High DIY-safe £80-160

What to check first

  1. Check if your room thermostat or programmer is turned up and calling for heat.
  2. Replace the batteries in your wireless room thermostat if applicable.
  3. Ensure any external emergency shut-off switches haven't been accidentally turned off.

Parts commonly replaced

  • External Thermostat
  • Wiring Link
  • User Interaction Controller

Related codes

Full explanation for 2 flashes green
2 flashes red

Your boiler has shut down because it has become too hot inside and needs time to cool down safely.

High DIY-safe £120-350

What to check first

  1. Check that all radiator valves are fully open to allow water to circulate.
  2. Ensure your system pressure is topped up correctly between 1 and 1.5 bar.
  3. Attempt to reset the boiler by turning the selector knob to 'R' for five seconds.
  4. Verify that the external pump (for heat-only systems) is running.

Parts commonly replaced

  • Over-temperature Thermostat
  • External Pump
  • Heat Exchanger (Flushing/Cleaning)
  • Flow/Return Sensor

Related codes

Full explanation for 2 flashes red
3 flashes green

Your boiler was working but the flame has unexpectedly gone out, causing the system to stop as a safety precaution.

High DIY-safe £100-£250

What to check first

  1. Check if other gas appliances (like a hob) are working to ensure your gas supply is active
  2. If you have a prepayment meter, check that you have sufficient credit
  3. Turn the selector switch to the reset position for five seconds and then back to 'On'

Parts commonly replaced

  • Flame sensing electrode
  • Gas valve
  • Spark generator

Related codes

Full explanation for 3 flashes green
3 flashes red

Your boiler is failing to light the gas burner or cannot stay lit, resulting in no heating or hot water.

High DIY-safe £100-£280

What to check first

  1. Check if other gas appliances, like a hob, are working to ensure gas is reaching the property
  2. Check that your prepaid gas meter has credit
  3. Switch the boiler off and on again (or turn the selector knob to 'R' for reset) to see if it clears the fault

Parts commonly replaced

  • Ignition Electrode
  • Flame Sensing Probe
  • Gas Valve
  • PCB (Printed Circuit Board)

Related codes

Full explanation for 3 flashes red
4 flashes green

Your boiler's internal components are having trouble talking to each other due to a wiring or electronic signal issue.

High Engineer only £100-£350

Parts commonly replaced

  • Main PCB
  • Wiring Harness
  • User Interface Panel

Related codes

Full explanation for 4 flashes green
4 flashes red

Your boiler's fan, which safely pushes exhaust gases out of the flue, is not spinning at the correct speed or has stopped working entirely.

High Engineer only £250-£450

Parts commonly replaced

  • Fan Assembly
  • Main PCB
  • Venturi Tube

Related codes

Full explanation for 4 flashes red
5 flashes green

Your boiler's internal computer has become confused or has developed a hardware fault, meaning it can no longer communicate correctly with its own components.

High Engineer only £250-450

Parts commonly replaced

  • Main PCB (Printed Circuit Board)
  • Parameters Plug

Related codes

Full explanation for 5 flashes green
5 flashes red

Your boiler's internal computer brain is having a communication breakdown and cannot read its required settings.

High Engineer only £180-£350

Parts commonly replaced

  • Printed Circuit Board (PCB)
  • Parameter Plug (PU)

Related codes

Full explanation for 5 flashes red
6 flashes green

Your boiler's electronic brain is experiencing a communication or internal error that is preventing it from managing the flame safely.

High Engineer only £250-£450

Parts commonly replaced

  • Main PCB (Printed Circuit Board)
  • Wiring harness

Related codes

Full explanation for 6 flashes green
6 flashes red

Your boiler is having trouble communicating with its own internal controls or the external thermostat, causing it to stop working for safety.

High Engineer only £100-£350

Parts commonly replaced

  • Main Printed Circuit Board (PCB)
  • Wiring Harness
  • External Controls Interface

Related codes

Full explanation for 6 flashes red
Digital codes
11.1 Error Codes - Auto Reset

Your boiler has detected a temporary issue and is waiting for the fault to clear itself before it attempts to start back up automatically.

Low DIY-safe £0-120

What to check first

  1. Check that the gas supply is turned on and credit is available
  2. Inspect the condensate pipe outside for signs of freezing or blockages
  3. Monitor the boiler to see if it clears and restarts on its own

Parts commonly replaced

  • None
  • Temperature Sensor
  • Condensate Trap

Related codes

Full explanation for 11.1 Error Codes - Auto Reset
11.2 Lockout Condition

Your boiler has stopped working to protect itself and needs to be manually restarted to clear a temporary glitch.

High DIY-safe £0-120

What to check first

  1. Locate the selector knob on the front of the boiler control panel.
  2. Turn the knob to the 'R' (Reset) position and hold it for at least 5 seconds.
  3. Release the knob and wait for the boiler to attempt to reignite.

Parts commonly replaced

  • None (Reset only)
  • Ignition Electrode
  • Gas Valve
Full explanation for 11.2 Lockout Condition
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