Ideal Response SE Fault codes & diagnostics

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

Combi Natural GasLPG 24-30 kW 2002-2005 Discontinued

Replaced by: isal

Download the Ideal Response SE manual The official installation & service manual (PDF) — the exact document these fault codes were verified against. PDF

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Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →

Severity at a glance

Each cell = one fault code. Hover to identify.
1 Emergency 36 High

All 37 documented codes

Tap any card for details

00

Your boiler has experienced a serious internal system error that has forced it to shut down completely for safety.

High Engineer only £150-350

Parts commonly replaced

  • Main PCB
  • Wiring harness

Related codes

01

Your boiler has detected an electrical fault in its internal wiring, which has caused it to shut down for safety reasons.

High Engineer only £150-300

Parts commonly replaced

  • Printed Circuit Board (PCB)
  • Wiring harness
  • Pressure sensor

Related codes

03

Your boiler has attempted to start but cannot detect a flame, so it has safely shut itself down to prevent gas from building up.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Flame rectification probe
  • Gas valve
04

Your boiler has detected an internal electronic error and has safely shut itself down to prevent damage, meaning you currently have no heating or hot water.

High Engineer only £150-350

Parts commonly replaced

  • Printed Circuit Board (PCB)
  • Wiring harness

Related codes

05

Your boiler's internal computer brain has developed a fault and can no longer control the heating system, meaning the boiler has shut down for safety.

High Engineer only £250-450

Parts commonly replaced

  • Main printed circuit board (PCB)

Related codes

06

Your boiler's internal computer has encountered a critical electronic fault and has shut down for safety.

High Engineer only £250-450

Parts commonly replaced

  • Main PCB

Related codes

07

Your boiler's internal computer has encountered a critical software or hardware error and needs to be reset or replaced by a professional.

High Engineer only £250-450

Parts commonly replaced

  • Main PCB
  • Wiring harness
10

Your boiler's main control computer is experiencing an internal error and cannot operate the system, meaning you currently have no heating or hot water.

High Engineer only £250-£450

Parts commonly replaced

  • Main printed circuit board (PCB)
12

Your boiler has detected that either the water pressure inside the system is too low or a safety sensor in the exhaust vent has triggered.

High Engineer only £150-250

Parts commonly replaced

  • Water pressure switch
  • Flue thermostat
  • Wiring harness
13

Your boiler's internal computer has encountered a critical error and is unable to manage the system safely, meaning your heating and hot water have stopped working.

High Engineer only £250-400

Parts commonly replaced

  • Main PCB
  • Wiring harness
Showing 11–20 of 37
14

Your boiler's internal computer has encountered a critical electronic error and expects to be shut down for safety.

High Engineer only £250-450

Parts commonly replaced

  • Main PCB
  • Wiring harness
15

The main electronic brain of your boiler has encountered an internal error and cannot process signals correctly, which means your heating and hot water will not work.

High Engineer only £250-450

Parts commonly replaced

  • Main Control PCB
  • Wiring Harness
16

Your boiler's main control computer is experiencing an internal electronic fault and can no longer safely operate.

High Engineer only £250-450

Parts commonly replaced

  • Main PCB
17

Your boiler's computer brain has encountered a permanent internal error, meaning the system has safely shut down and stopped providing heating and hot water.

High Engineer only £250-450

Parts commonly replaced

  • Main PCB
18

Your boiler has detected that the water inside the system is getting much hotter than it should be and has shut down to prevent damage.

High Engineer only £150-300

Parts commonly replaced

  • NTC Thermistor
  • Pump
  • Heat exchanger
19

Your boiler has detected that the water returning to it is much hotter than it should be, causing the system to shut down to prevent damage.

High Engineer only £120-250

Parts commonly replaced

  • Return temperature sensor
  • Central heating pump
  • System filter
24

Your boiler's temperature sensors have been incorrectly wired or swapped, causing the system to misread the water flow and preventing it from operating safely.

High Engineer only £120-200

Parts commonly replaced

  • NTC Sensor
  • Wiring harness
25

Your boiler has detected that the water inside is heating up far too quickly and has shut itself down to prevent damage.

High Engineer only £150-300

Parts commonly replaced

  • Pump
  • System filter
  • Heat exchanger
26

Your boiler is failing to ignite because it is not receiving enough gas to run safely.

High Engineer only £120-250

Parts commonly replaced

  • Gas valve
  • Gas regulator
  • Gas meter
28

Your boiler has stopped working because the mechanical fan responsible for venting combustion gases is not spinning or communicating with the control system.

High Engineer only £180-350

Parts commonly replaced

  • Fan assembly
  • Wiring harness
  • Printed Circuit Board (PCB)
Showing 21–30 of 37
29

Your boiler is struggling to detect that its internal fan is spinning correctly, which causes it to shut down for safety reasons.

High Engineer only £180-350

Parts commonly replaced

  • Fan assembly
  • Wiring harness
  • Printed Circuit Board (PCB)
30

Your boiler has detected that the water temperature is changing too drastically between the two main sensors, causing it to shut down for safety.

High Engineer only £150-300

Parts commonly replaced

  • NTC Temperature Sensors
  • Central Heating Pump
  • Plate Heat Exchanger
31

Your boiler has stopped working because one of its temperature sensors has developed an electrical fault and is giving the computer false information.

High Engineer only £120-180

Parts commonly replaced

  • Flow NTC Sensor
  • Wiring Harness
32

Your boiler has detected a faulty sensor reading, which is preventing the hot water or heating from working correctly.

High Engineer only £120-220

Parts commonly replaced

  • Domestic Hot Water (DHW) NTC Thermistor
  • Wiring Harness
36

Your boiler has lost the ability to read the water temperature correctly because a sensor connection has been broken or has failed.

High Engineer only £120-220

Parts commonly replaced

  • Flow NTC sensor
  • Wiring harness

Related codes

37

Your boiler has lost its connection to the sensor that monitors the hot water temperature, meaning it cannot accurately manage the heating process.

High Engineer only £120-220

Parts commonly replaced

  • Domestic Hot Water (DHW) NTC Thermistor
  • Wiring harness
41

Your boiler's internal computer has encountered a critical electronic error and cannot safely operate, meaning you currently have no heating or hot water.

High Engineer only £250-450

Parts commonly replaced

  • Main PCB (Printed Circuit Board)
42

Your boiler's internal computer has encountered a critical electronic error and cannot safely operate, meaning you currently have no heating or hot water.

High Engineer only £250-450

Parts commonly replaced

  • Main PCB
  • Wiring harness

Related codes

60

Your boiler's internal computer has encountered a critical error preventing it from running safely, so it has shut down to protect itself.

High Engineer only £250-450

Parts commonly replaced

  • Main PCB
  • Control Board
82

Your boiler has stopped working because the internal fan, which clears exhaust gases, is failing to spin as it should.

High Engineer only £180-350

Parts commonly replaced

  • Fan assembly
  • Fan harness
  • PCB
Showing 31–37 of 37
83

Your boiler's internal electrical control unit is failing to communicate with the fan, which means the system cannot safely start the heating process.

High Engineer only £250-450

Parts commonly replaced

  • Main PCB
  • Wiring harness
  • Fan

Related codes

84

Your boiler has detected that it is receiving electricity but is failing to deliver the gas pressure required to ignite the flame, meaning you have no heating or hot water.

High Engineer only £150-350

Parts commonly replaced

  • Gas valve
  • PCB
  • Wiring harness
85

Your boiler has detected an issue with the fuel and air mixture or is struggling to light correctly, so it has safely shut itself down to prevent any risk.

Emergency Engineer only £180-350

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Flame rectification probe
86

Your boiler has stopped working because the water pressure inside your heating system has dropped too low.

High DIY-safe £0-£120

What to check first

  1. Locate the external filling loop (a silver flexi-hose) near the boiler.
  2. Open the valves at both ends of the loop to allow water into the system.
  3. Monitor the pressure gauge on the front of the boiler until it reaches 1.5 bar, then firmly close both valves.

Parts commonly replaced

  • Pressure relief valve
  • Pressure gauge
  • Expansion vessel
410

Your boiler’s internal computer has encountered a critical error and needs a professional to reset or replace the main control board.

High Engineer only £250-£450

Parts commonly replaced

  • Printed Circuit Board (PCB)
  • Internal Wiring Harness

Related codes

424

Your boiler has detected that the temperature sensors monitoring the water going out and coming back are swapped or wired incorrectly, preventing it from heating safely.

High Engineer only £90-180

Parts commonly replaced

  • Flow NTC sensor
  • Return NTC sensor
  • Wiring loom
460

Your boiler's computer control board has developed an internal electrical fault and is unable to communicate properly with the system.

High Engineer only £280-£450

Parts commonly replaced

  • Main Printed Circuit Board (PCB)
  • Wiring harness

1 operating states & engineer diagnostics

Not faults — these are normal operating states. Tap to expand.