Ferroli Arena Fault codes & diagnostics

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

Combi Natural Gas Discontinued
GC Number 47-267-25
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Severity at a glance

Each cell = one fault code. Hover to identify.
1 Emergency 19 High 4 Medium 11 Low
Just want the most common Ferroli Arena faults?
The top 6 problems in plain English — with causes, DIY checks and repair costs.
Fault codes

All 35 documented codes

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10

Your boiler is not turning on because it isn't receiving a signal that a flame has successfully lit.

High DIY-safe £120-250

What to check first

  1. Check that your gas meter supply valve and the gas isolation valve near the boiler are both fully open.
  2. Check if other gas appliances in your home, such as a gas hob, are working to confirm gas supply.
  3. Locate the Reset button on the boiler control panel and press it for a few seconds to attempt a restart.

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Ignition lead

Related codes

Full explanation for 10
12

Your boiler is not starting because it is unable to ignite its flame.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • PCB

Related codes

Full explanation for 12
13

Your boiler is trying to start but the flame is not igniting, meaning you currently have no heating or hot water.

High DIY-safe £120-250

What to check first

  1. Check that your gas supply is working by testing another gas appliance like a hob
  2. Ensure the gas isolation valve near the boiler is turned to the fully open position
  3. Press the RESET button on the front control panel once to attempt a restart

Parts commonly replaced

  • Ignition electrode
  • Ignition lead
  • Gas valve

Related codes

Full explanation for 13
14

Your boiler is trying to start but the flame isn't catching, meaning you currently have no heating or hot water.

High DIY-safe £120-250

What to check first

  1. Check that your gas meter control valve is turned to the 'on' position.
  2. Ensure any gas isolation valves located underneath the boiler are fully open.
  3. Press the reset button on the boiler control panel once to attempt a restart.

Parts commonly replaced

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

Related codes

Full explanation for 14
15

Your boiler has stopped working because it cannot light the internal flame needed to heat your water or radiators.

High DIY-safe £120-250

What to check first

  1. Check that your gas supply is on by ensuring other gas appliances like a hob are working.
  2. Verify the gas isolation valve near your boiler and at the main meter are both in the open position.
  3. Press the RESET button on the boiler control panel once to see if it restarts.

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Ignition transformer

Related codes

Full explanation for 15
16

Your boiler is failing to ignite the flame needed to heat your home's water and radiators.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Flame rectification probe

Related codes

Full explanation for 16
17

Your boiler is failing to ignite because it isn't receiving enough gas to produce a flame.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • PCB

Related codes

Full explanation for 17
18

Your boiler is failing to light because it cannot detect a flame, meaning you currently have no heating or hot water.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Ignition transformer

Related codes

Full explanation for 18
19

Your boiler is not receiving gas or cannot ignite, meaning you currently have no heating or hot water until the issue is cleared.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • PCB

Related codes

Full explanation for 19
20

Your boiler is trying to start but the flame is not catching, likely because it is not receiving a gas supply.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • PCB

Related codes

Full explanation for 20
Showing 11–20 of 35
21

Your boiler is currently unable to ignite, which means it cannot provide heat or hot water because it is not sensing a flame.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • PCB

Related codes

Full explanation for 21
23

Your boiler is not receiving enough gas or failing to ignite, meaning it cannot produce heat or hot water.

High DIY-safe £120-250

What to check first

  1. Check that your gas meter emergency control valve is turned to the fully open position.
  2. Verify the gas isolation valve located underneath the boiler is open.
  3. Check if other gas appliances in your home, such as a gas hob, are working to confirm gas supply.
  4. Press the 'Reset' button on the boiler control panel once.

Parts commonly replaced

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

Related codes

Full explanation for 23
24

Your boiler is not firing up because it cannot detect a flame, meaning you currently do not have any heating or hot water.

High DIY-safe £100-£250

What to check first

  1. Check that your gas supply is turned on at the meter and the boiler isolation valve.
  2. Ensure you have credit on your gas meter if you are on a prepayment plan.
  3. Press the Reset button on the front of the boiler once to see if it clears the fault.
  4. Check if other gas appliances in your home, like a cooker, are working to confirm gas is reaching the property.

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • PCB

Related codes

Full explanation for 24
25

Your boiler is trying to start but cannot detect a flame, meaning it is currently unable to provide heating or hot water.

High DIY-safe £120-250

What to check first

  1. Check that your gas supply is turned on at the meter and the boiler isolation valve.
  2. Ensure any other gas appliances are working to rule out a main gas supply issue.
  3. Press the reset button on your boiler control panel once to see if it restarts.

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Ignition lead

Related codes

Full explanation for 25
26

Your boiler is currently unable to ignite, meaning it cannot produce heating or hot water for your home.

High DIY-safe £120-250

What to check first

  1. Check that your gas supply is active by turning on a gas hob or checking other appliances
  2. Ensure the gas isolation valve near the boiler and the main gas meter are fully open
  3. Press the physical RESET button on the boiler control panel once to attempt a restart

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • PCB

Related codes

Full explanation for 26
30

Your boiler has temporarily paused operation because a sensor detected that a temperature or pressure reading has briefly drifted outside of its normal operating limits.

Low Engineer only £90-180

Parts commonly replaced

  • NTC temperature sensor
  • System pressure sensor
  • Printed circuit board

Related codes

Full explanation for 30
31

Your boiler has temporarily paused because it detected a slight inconsistency in its internal readings, but it will restart automatically once things return to normal.

Low Engineer only

Parts commonly replaced

  • Temperature sensor
  • Wiring harness

Related codes

Full explanation for 31
32

Your boiler is temporarily pausing its operation until its internal temperature or pressure readings return to a safe and normal level.

Low Engineer only

Parts commonly replaced

  • NTC Temperature sensor
  • System pressure switch
  • Main circuit board (PCB)

Related codes

Full explanation for 32
34

Your boiler has temporarily paused because it detected a temperature or pressure reading outside of its standard operating limit, and it will attempt to restart itself once conditions stabilise.

Low Engineer only £90-180

Parts commonly replaced

  • NTC Temperature Sensor
  • Pressure Sensor
  • Control PCB

Related codes

Full explanation for 34
35

Your boiler has detected a temporary issue and stopped working as a safety precaution, but it should restart itself automatically once the internal temperature or pressure returns to normal.

Low Engineer only £90-180

Parts commonly replaced

  • NTC temperature sensor
  • Central heating pump

Related codes

Full explanation for 35
Showing 21–30 of 35
36

Your boiler has detected a temporary issue with its internal heat levels or water flow and has paused itself while it waits for conditions to return to normal.

Low Engineer only £100-200

Parts commonly replaced

  • Temperature sensor
  • Pump
  • Circuit board
Full explanation for 36
37

Your boiler has temporarily paused because it detected an operating value, such as water pressure or pressure levels, outside of its normal range, but it should restart itself once conditions stabilise.

Low Engineer only £90-180

Parts commonly replaced

  • Pressure sensor
  • System pressure gauge
  • Expansion vessel

Related codes

Full explanation for 37
38

Your boiler is temporarily pausing because it has detected a reading outside of its normal operating parameters, but it should restart itself once conditions return to normal.

Medium DIY-safe

What to check first

  1. Check the system pressure gauge and top up to 1.5 bar if low
  2. Ensure all radiator valves are open to allow correct circulation
  3. Wait for the boiler to cool down if it has recently overheated
  4. Press the reset button if the boiler does not restart automatically

Parts commonly replaced

  • NTC Sensor
  • System Pressure Sensor
  • Main Control Board

Related codes

Full explanation for 38
39

Your boiler has detected a temporary inconsistency in its operating temperature, so it has paused itself to stay safe and will likely restart automatically once it cools down.

Low Engineer only £100-250

Parts commonly replaced

  • NTC temperature sensor
  • System bypass valve
  • Central heating pump

Related codes

Full explanation for 39
40

Your boiler has detected a temporary temperature issue and is pausing itself to prevent damage, but it should restart automatically once cooled.

Medium DIY-safe £100-200

What to check first

  1. Check that all radiator valves are fully open
  2. Check the system pressure is between 1 and 1.5 bar
  3. Wait for the boiler to cool and restart automatically
  4. Ensure there is no air trapped in the system by bleeding radiators

Parts commonly replaced

  • NTC temperature sensor
  • Pump
  • Primary heat exchanger

Related codes

Full explanation for 40
41

Your boiler has detected a temporary operating temperature anomaly and has turned itself off briefly to protect the system before it should automatically restart.

Low Engineer only £90-180

Parts commonly replaced

  • NTC temperature sensor
  • System bypass valve
  • Central heating pump

Related codes

Full explanation for 41
42

Your boiler has temporarily paused itself because a sensor reading momentarily went outside its normal limit, but will restart automatically once conditions stabilize.

Low Engineer only £90-180

Parts commonly replaced

  • NTC temperature sensor
  • System bypass valve
  • Central heating pump

Related codes

Full explanation for 42
43

Your boiler has detected that the water inside the system has become too hot and has temporarily turned itself off to cool down, which it should fix automatically.

Medium Engineer only £120-250

Parts commonly replaced

  • NTC temperature sensor
  • Pump
  • Heat exchanger

Related codes

Full explanation for 43
45

Your boiler has detected a temporary temperature mismatch and has paused itself to prevent damage, but it should restart automatically once it cools down.

Low Engineer only £100-250

Parts commonly replaced

  • NTC temperature sensor
  • System bypass valve
  • Central heating pump

Related codes

Full explanation for 45
49

Your boiler has switched itself off because it got too hot and needs time to cool down before it can safely restart.

High DIY-safe £120-280

What to check first

  1. Turn the boiler off and allow it to cool for 20 minutes
  2. Ensure all radiator valves are fully open to allow water to circulate
  3. Check that your system pressure is between 1 and 1.5 bar
  4. Press the Reset button on the control panel

Parts commonly replaced

  • Overheat Thermostat
  • Circulation Pump
  • Main Heat Exchanger (Cleaning or Replacement)

Related codes

Full explanation for 49
Showing 31–35 of 35
50

Your boiler has shut down because a sensor has detected that the water inside the heating circuit has reached an unsafely high temperature.

High DIY-safe £120-250

What to check first

  1. Check that all radiator valves are fully open
  2. Ensure the boiler pressure is between 1 and 1.5 bar
  3. Reset the boiler using the reset button once the unit has cooled down

Parts commonly replaced

  • Overheat Thermostat
  • Central Heating NTC Sensor
  • Circulation Pump

Related codes

Full explanation for 50
114

Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.

High DIY-safe £0-160

What to check first

  1. Locate the filling loop (usually a silver braided hose with small valves under the boiler).
  2. Slowly open the valve(s) until you hear water entering the system.
  3. Watch the pressure gauge and close the valves when the needle reaches between 1 and 1.5 bar.
  4. Reset the boiler to clear the fault code.

Parts commonly replaced

  • Water pressure switch
  • Filling loop valve
  • Expansion vessel

Related codes

Full explanation for 114
A-4

Your boiler has stopped providing hot water because it is having trouble reading the temperature of the water used for your taps.

Medium Engineer only £120-220

Parts commonly replaced

  • DHW NTC sensor
  • Wiring harness

Related codes

Full explanation for A-4
F2

Your boiler has detected a flame even though it is not supposed to be running, which is a safety lockout to prevent potential issues.

Emergency Engineer only £150-300

Parts commonly replaced

  • Ionization electrode
  • Printed Circuit Board (PCB)

Related codes

Full explanation for F2
Radiators cold in winter

Your boiler is failing to circulate heat to your radiators, likely because the internal pump is stuck or the system is failing to detect the correct temperature.

High Engineer only £180-350

Parts commonly replaced

  • Central heating pump
  • Flow temperature sensor (NTC)
  • Pump capacitor

Related codes

Full explanation for Radiators cold in winter
Status & diagnostic codes

1 operating states & engineer diagnostics

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

51 Status Your boiler has sensed that the temperature inside the unit is too low and has triggered a safety mode to prevent the pipes from freezing.