Alpha Intec2 30SE Fault codes & diagnostics

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

System Natural Gas 30 kW 2014-2018 Discontinued

Replaced by: E-Tec S

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9 Emergency 51 High 6 Medium 1 Low

All 67 documented codes

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01

Your boiler is failing to light the burner, which means it cannot produce any heat or hot water.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Printed Circuit Board

Related codes

02

Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.

High Engineer only £120-250

Parts commonly replaced

  • Pump
  • Diverter valve
  • Overheat thermostat
  • Primary heat exchanger

Related codes

03

Your boiler has detected that the exhaust gases leaving your home are becoming dangerously hot and has shut itself down to prevent damage or safety risks.

Emergency Engineer only £150-300

Parts commonly replaced

  • Flue sensor
  • Primary heat exchanger
  • Pump

Related codes

04

Your boiler has lost its electrical communication with the gas supply component, meaning it cannot safely ignite to provide heating or hot water.

Emergency Engineer only £150-250

Parts commonly replaced

  • Gas valve
  • Wiring harness

Related codes

05

Your boiler has detected an issue with the sensor that measures the flow of water for your central heating, which is likely preventing the system from heating your home.

High Engineer only £150-250

Parts commonly replaced

  • CH flow sensor
  • Wiring harness

Related codes

06

Your boiler is struggling to accurately measure the temperature of your hot water, which means it has stopped providing it to prevent system overheating.

High Engineer only £120-200

Parts commonly replaced

  • DHW NTC Sensor
  • Wiring harness

Related codes

08

Your boiler has attempted to restart itself five times after failing to operate, and has now locked itself out for safety reasons.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • PCB

Related codes

10

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

High DIY-safe £80-120

What to check first

  1. Locate the external filling loop, usually a small silver braided hose with one or two valves located underneath the boiler.
  2. Slowly open the valve(s) to allow mains water into the system while watching the pressure gauge on the front of the boiler.
  3. Close the valve(s) firmly once the needle sits between 1.0 and 1.5 bar on the gauge and check the fault code has cleared.

Parts commonly replaced

  • Pressure relief valve
  • Expansion vessel
  • Filling loop

Related codes

12

Your boiler's computer is confused because its internal settings, such as whether it should be heating water or radiators, do not align with the physical parts installed.

High Engineer only £120-250

Parts commonly replaced

  • Printed Circuit Board (PCB)
  • Wiring harness
15

Your boiler's computer is confused because it has detected a mismatch between its internal settings and the actual physical setup of the heating system.

High Engineer only £150-300

Parts commonly replaced

  • Printed Circuit Board (PCB)
  • Link wire

Related codes

Showing 11–20 of 67
16

Your boiler has stopped working because it cannot properly clear exhaust gases, meaning it is currently unable to provide heating or hot water.

High Engineer only £180-350

Parts commonly replaced

  • Fan assembly
  • Wiring harness
  • PCB

Related codes

20

Your boiler has detected a flame signal when it shouldn't be there, which means it has safely shut down to prevent a potential hazard.

Emergency Engineer only £150-300

Parts commonly replaced

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

Related codes

23

Your boiler's computer is confused because it has detected a mismatch between its internal settings and how the plumbing system is actually set up.

High Engineer only £120-250

Parts commonly replaced

  • Main PCB
  • Configuration link/plug

Related codes

24

Your boiler's control panel detects that one of the buttons is jammed or held down, which is preventing the system from operating normally.

Medium DIY-safe £100-200

What to check first

  1. Turn off the electrical supply to the boiler at the fused spur
  2. Inspect the front control panel buttons for any debris, dirt, or signs of being physically stuck
  3. Gently wiggle and press each button multiple times to see if they release and click freely
  4. Turn the electrical supply back on and check if the error is cleared

Parts commonly replaced

  • Control panel interface board
  • User interface fascia
29

Your boiler has detected an issue with the sensor that monitors the temperature of the gases leaving your flue, causing it to shut down for safety.

High Engineer only £150-250

Parts commonly replaced

  • Flue gas temperature sensor
  • Wiring harness
31

Your boiler has lost its connection to your digital thermostat or programmer, meaning it doesn't know when to turn the heating on.

High Engineer only £120-250

Parts commonly replaced

  • Alpha Climatic control unit
  • PCB (Printed Circuit Board)
  • Wiring loom
36

The boiler's control system is experiencing a communication error, which prevents it from operating correctly.

High Engineer only £150-300

Parts commonly replaced

  • Main PCB
  • Wiring harness

Related codes

37

Your boiler is failing to start because it is not receiving the correct amount of electrical power from your home's mains supply.

High Engineer only £120-250

Parts commonly replaced

  • PCB (Printed Circuit Board)
  • Wiring harness
  • Fused spur

Related codes

38

Your boiler is struggling to keep its flame lit, which means it will stop providing heating and hot water until the issue is resolved.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • PCB

Related codes

43

Your boiler is struggling to keep its internal flame lit while it is running, likely because it is having trouble breathing due to strong winds or a blockage in its external exhaust pipe.

High Engineer only £120-250

Parts commonly replaced

  • Flame rectification electrode
  • Gas valve
  • Ignition lead

Related codes

Showing 21–30 of 67
45

Your boiler has detected that the water is not circulating efficiently through your heating system, as it is coming back to the boiler much cooler than it left.

Medium Engineer only £150-300

Parts commonly replaced

  • Central heating pump
  • System filter
  • Temperature sensors
46

Your boiler has stopped working because a safety link or an external safety device, such as a frost thermostat or pipe protection sensor, has been triggered or disconnected.

High Engineer only £120-250

Parts commonly replaced

  • External safety link
  • External thermostat/sensor
  • Wiring loom

Related codes

47

Your boiler is getting too hot inside the exhaust system and has automatically slowed down to protect itself from overheating.

High Engineer only £150-300

Parts commonly replaced

  • Flue thermostat
  • Primary heat exchanger
  • NTC thermistor

Related codes

51

Your boiler is struggling to talk to your wireless thermostat, which means it doesn't know when to turn your heating on or off.

High DIY-safe £100-250

What to check first

  1. Check if the batteries in your wireless room thermostat are dead and replace them with high-quality alkaline batteries.
  2. Turn the power to the boiler off at the fused spur for one minute, then turn it back on to reset the connection.
  3. Ensure there are no new large electronic devices or metal obstructions placed between the thermostat and the boiler receiver.

Parts commonly replaced

  • Climatic RF receiver
  • PCB
  • Wireless thermostat unit
59

Your boiler is struggling because the electricity supply it is receiving is unstable or not the standard frequency required.

High Engineer only £120-250

Parts commonly replaced

  • Printed Circuit Board (PCB)
  • Electrical wiring harness

Related codes

60

Your boiler is unable to move the hot water around your system because the device responsible for circulating it has stopped working.

High Engineer only £180-300

Parts commonly replaced

  • Central Heating Pump
  • Pump Head
  • Wiring Harness

Related codes

61

Your boiler is struggling because there is trapped air inside the system, which is preventing water from circulating properly to heat your home.

Medium DIY-safe £80-150

What to check first

  1. Turn off the power to the boiler and let it cool down for 30 minutes.
  2. Go to your radiators and use a bleed key to release any trapped air until water starts to trickle out.
  3. Check the pressure gauge on the front of the boiler and top it up to 1.5 bar using the filling loop if it has dropped.

Parts commonly replaced

  • Automatic air vent
  • Central heating pump
  • Expansion vessel

Related codes

62

Your boiler has lost its saved settings and needs a professional recalibration to safely manage the mix of gas and air used for heating.

High Engineer only £120-250

Parts commonly replaced

  • Printed Circuit Board (PCB)

Related codes

72

Your boiler’s internal settings have become scrambled, meaning it has forgotten how to manage its own fuel and air levels correctly.

High Engineer only £120-200

Parts commonly replaced

  • Control PCB

Related codes

73

Your boiler has detected a confusing temperature difference between its internal sensors and has shut down as a precaution to prevent overheating.

High Engineer only £150-250

Parts commonly replaced

  • Flow NTC sensor
  • Safety NTC sensor
  • Wiring harness

Related codes

Showing 31–40 of 67
74

Your boiler has detected a communication error with its internal temperature monitoring system, preventing it from operating safely.

High Engineer only £150-250

Parts commonly replaced

  • NTC sensor
  • Wiring harness
  • Printed Circuit Board (PCB)
78

Your boiler has detected an issue with the internal components that manage the gas supply, meaning it has safely shut itself down to prevent unsafe operation.

Emergency Engineer only £150-300

Parts commonly replaced

  • Gas valve
  • PCB

Related codes

79

Your boiler has detected an issue with the internal component that controls the gas supply, meaning it has safely shut itself down to prevent any risk.

Emergency Engineer only £150-300

Parts commonly replaced

  • Gas valve
  • PCB (Printed Circuit Board)
  • Wiring harness

Related codes

80

Your boiler has detected an internal electrical problem that is preventing it from safely opening the gas supply, so it has shut down to protect the system.

High Engineer only £250-450

Parts commonly replaced

  • Main printed circuit board (PCB)
  • Gas valve
84

Your boiler has detected that it is not receiving enough gas to work properly, so it has lowered its performance to keep itself safe while it runs in a limited emergency mode.

High Engineer only £120-250

Parts commonly replaced

  • Gas valve
  • Gas meter regulator
  • Gas control assembly
87

Your boiler has detected a failure in the system that supplies fuel for the flame, so it has safely shut down to prevent any unsafe operation.

High Engineer only £200-400

Parts commonly replaced

  • Gas valve
  • Printed Circuit Board (PCB)
89

Your boiler is struggling to keep a steady flame, causing it to shut down because it cannot safely maintain the fire needed to heat your home.

High Engineer only £150-350

Parts commonly replaced

  • Flame rectification electrode
  • Gas valve
  • Ignition lead
  • Printed Circuit Board (PCB)

Related codes

90

Your boiler has detected an issue with the quality of the flame and has shut down for safety reasons to prevent incomplete combustion.

Emergency Engineer only £120-250

Parts commonly replaced

  • Flame rectification electrode
  • Gas valve
  • PCB

Related codes

91

Your boiler is trying to start but cannot detect the flame, so it is shutting down for safety reasons to prevent gas buildup.

High Engineer only £150-350

Parts commonly replaced

  • Ignition electrode
  • Flame sensor
  • Gas valve
  • PCB

Related codes

92

Your boiler is struggling to push air through safely and has reached its physical limit, causing it to shut down to prevent unsafe operation.

High Engineer only £180-350

Parts commonly replaced

  • Fan assembly
  • Flue system components
  • Air pressure switch
  • PCB

Related codes

Showing 41–50 of 67
93

Your boiler has detected an abnormal flame signal, meaning it cannot safely regulate its internal combustion process and has shut down to prevent damage.

High Engineer only £150-300

Parts commonly replaced

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

Related codes

94

Your boiler has detected that it cannot clear gases properly, so it has safely shut itself down to prevent any unsafe build-up.

High Engineer only £150-350

Parts commonly replaced

  • Fan unit
  • Venturi
  • Air pressure switch
  • Flue seals

Related codes

95

Your boiler is struggling to keep its flame lit, which is causing it to quickly turn itself off and on again.

High Engineer only £150-300

Parts commonly replaced

  • Ignition electrode
  • Flame rectification probe
  • Gas valve

Related codes

96

Your boiler is struggling to breathe because the pipe that vents exhaust gases outside is blocked or obstructed.

Emergency Engineer only £120-250

Parts commonly replaced

  • Flue terminal
  • Fan assembly
  • Air pressure switch
  • Venturi

Related codes

98

Your boiler's computer system has detected too many internal errors and has shut down for safety reasons.

High Engineer only £150-350

Parts commonly replaced

  • Printed Circuit Board (PCB)
  • Wiring harness
CE

Your boiler is receiving an unusual signal from an external weather-sensing device linked to a central control system, causing it to pause normal operation.

Medium Engineer only £120-250

Parts commonly replaced

  • External weather sensor
  • System supervisor module
  • Wiring harness

Related codes

E01

Your boiler has failed to light the flame needed to produce heat and hot water.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • PCB

Related codes

E02

Your boiler has detected that it is getting too hot and has automatically shut down to prevent damage or dangerous overheating.

High Engineer only £120-250

Parts commonly replaced

  • Pump
  • Plate heat exchanger
  • NTC thermistor
  • Safety thermostat

Related codes

E03

Your boiler has detected that hot exhaust gases are not escaping properly and has shut itself down as a vital safety precaution.

Emergency Engineer only £120-250

Parts commonly replaced

  • Flue thermostat
  • Flue assembly
  • PCB

Related codes

E04

Your boiler has detected an issue with its internal electrical connections, preventing it from starting up safely.

High Engineer only £150-250

Parts commonly replaced

  • Control PCB
  • Wiring harness
  • Gas valve

Related codes

Showing 51–60 of 67
E05

Your boiler has stopped working because it is unable to accurately measure the temperature of the water circulating through your heating system.

High Engineer only £120-220

Parts commonly replaced

  • Flow NTC Sensor
  • Wiring harness

Related codes

E06

Your boiler is struggling to accurately measure the temperature of the water being heated for your taps and shower.

Medium Engineer only £120-200

Parts commonly replaced

  • DHW NTC thermistor

Related codes

E08

Your boiler has attempted to restart itself too many times due to an underlying fault, so it has now locked itself to prevent further issues.

High Engineer only £120-250

Parts commonly replaced

  • Ignition lead
  • Ignition electrode
  • Gas valve
  • PCB

Related codes

E10

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, usually two silver valves connected by a small braided hose underneath the boiler.
  2. Gradually open the valves to allow water into the system until the pressure gauge reads between 1.0 and 1.5 bar.
  3. Close both valves tightly and ensure the boiler resets its display.

Parts commonly replaced

  • Pressure relief valve
  • Expansion vessel
  • Filling loop
E15

Your boiler's temperature sensor is providing incorrect readings, so the system has shut down to prevent it from overheating.

High Engineer only £120-200

Parts commonly replaced

  • Return NTC thermistor
  • Wiring harness
E16

Your boiler has detected that the internal fan responsible for safely removing exhaust gases is not spinning correctly or has lost its electrical connection.

High Engineer only £180-350

Parts commonly replaced

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

Related codes

E20

Your boiler has detected a flame when it is not supposed to be lit, which is a safety mechanism preventing it from starting up to protect your home.

Emergency Engineer only £150-300

Parts commonly replaced

  • Printed circuit board (PCB)
  • Flame sensing electrode

Related codes

E24

Your boiler's electronic control panel is experiencing a communication error, which means it cannot register your settings or operate correctly.

High Engineer only £150-300

Parts commonly replaced

  • User interface PCB
  • Main control board
E31

Your boiler has lost its connection to the digital controller or thermostat, meaning it cannot receive instructions on when to turn the heating or hot water on.

Medium Engineer only £120-200

Parts commonly replaced

  • PCB
  • Communication cable
  • Remote thermostat
E37

Your boiler is struggling because the electrical voltage being supplied to it is lower than it needs to be to operate correctly.

High Engineer only £100-250

Parts commonly replaced

  • Main PCB
  • Wiring harness

Related codes

Showing 61–67 of 67
E38

Your boiler has detected that the burner has gone out or failed to ignite, so it has safely shut itself down to prevent gas from building up.

High Engineer only £150-300

Parts commonly replaced

  • Ignition electrode
  • Flame rectification probe
  • Gas valve
  • PCB

Related codes

E43

Your boiler is having trouble staying lit and keeps cutting out because it cannot confirm the flame is burning correctly.

High Engineer only £150-300

Parts commonly replaced

  • Flame rectification electrode
  • Ignition lead
  • Gas valve
  • PCB
E62

Your boiler’s internal computer has flagged that it needs a professional safety recalibration to ensure it is burning gas correctly.

High Engineer only £120-200
E72

Your boiler's computer needs to reset and recalibrate its internal heating settings to function correctly again.

High Engineer only £120-200

Parts commonly replaced

  • Gas valve
  • PCB
E76

Your boiler's internal fuel control system is experiencing an electrical issue, meaning it cannot safely regulate the gas supply to produce heat.

High Engineer only £150-300

Parts commonly replaced

  • Gas valve
  • PCB
ERR>07

Your boiler is currently running in a special testing mode designed for engineers to check flue gases, rather than a system failure.

Low DIY-safe

What to check first

  1. Locate the mode switch on your boiler or the separate Climatic controller unit
  2. Turn off the 'Chimney Sweep' or 'Service' mode setting
  3. Restart the boiler to return to normal operation
F0

Your boiler's computer is reporting an issue because the settings do not match the length of the exhaust pipe installed on your property.

High Engineer only £120-250

Parts commonly replaced

  • Main PCB