Ferroli Tempra Fault codes & diagnostics

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

Combi Natural Gas 24-28 kW 2005-2010 Discontinued

Replaced by: Ferroli Modena

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.
11 High 1 Medium 4 Low
Just want the most common Ferroli Tempra faults?
The top 6 problems in plain English — with causes, DIY checks and repair costs.
Fault codes

All 16 documented codes

Tap any card for details

LED / flash-pattern codes
4 (Flashing Light)

Your boiler is working correctly and is simply waiting for your thermostat to tell it to turn the heating on.

Low DIY-safe

What to check first

  1. Check that your room thermostat is turned up high enough to call for heat
  2. Ensure your heating programmer or timer is set to an 'ON' period
  3. Check that any thermostatic radiator valves (TRVs) are turned to an open position
Full explanation for 4 (Flashing Light)
4 (Flashing)

Your boiler is currently in standby mode for the central heating and is not actually reporting a fault.

Low DIY-safe

What to check first

  1. Check that your room thermostat is turned up high enough to call for heat.
  2. Ensure your programmer or timer is set to an 'On' period.
  3. Verify that the boiler mode is set to 'Winter' (Heating and Hot Water) rather than 'Summer' only.
Full explanation for 4 (Flashing)
5 (Flashing Light)

Your boiler has stopped working because the water pressure in your radiators has dropped too low to operate safely.

High DIY-safe £0-120

What to check first

  1. Locate the filling loop (a silver flexible hose usually underneath the boiler)
  2. Open the one or two taps on the hose slowly until you hear water flowing
  3. Close the taps once the pressure gauge on the boiler reaches between 1.0 and 1.5 bar

Parts commonly replaced

  • Filling loop valve
  • Expansion vessel
  • Pressure sensor
Full explanation for 5 (Flashing Light)
5 (Flashing)

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

High DIY-safe £0-120

What to check first

  1. Locate the filling loop (usually a silver braided hose with small valves) underneath the boiler.
  2. Slowly open the valves until you hear water flowing and watch the pressure gauge.
  3. Close the valves tightly once the needle reaches between 1 and 1.5 bar.

Parts commonly replaced

  • Filling loop
  • Pressure sensor
  • Expansion vessel
Full explanation for 5 (Flashing)
Digital codes
4 (Permanent Light)

Your boiler is currently operating normally to provide heating to your radiators.

Low DIY-safe

What to check first

  1. Check if your room thermostat is turned up
  2. Ensure your heating programmer is set to 'ON'
  3. If the light stays on when you want the heating off, check for a stuck thermostat
Full explanation for 4 (Permanent Light)
4 (Permanent)

Your boiler thinks the central heating should be running constantly, which can lead to overheating or your radiators staying on when they shouldn't.

Medium Engineer only £120-280

Parts commonly replaced

  • Central heating temperature sensor (NTC)
  • Printed Circuit Board (PCB)
Full explanation for 4 (Permanent)
5 (Permanent Light)

Your boiler is receiving electrical power and is currently in standby mode or normal operation.

Low DIY-safe

What to check first

  1. No action is required as this indicates the power is on
  2. Turn on your thermostat or hot water tap to start the boiler
  3. Check that the selector dial is set to the correct mode (Winter or Summer)
Full explanation for 5 (Permanent Light)
5 (Permanent)

Your boiler has detected an internal electrical supply error or a fault within the main control board that requires a professional reset.

High Engineer only £180-350

Parts commonly replaced

  • Main Printed Circuit Board (PCB)
  • Wiring Harness

Related codes

Full explanation for 5 (Permanent)
F1

Your boiler has failed to ignite, meaning it cannot create the flame needed to provide you with heating or hot water.

High DIY-safe £100-300

What to check first

  1. Check that your gas meter has credit and the isolation valve is open.
  2. Try to reset the boiler by pressing the 'Reset' button (or turning the knob to 'R' and back).
  3. Check if other gas appliances in your home, such as a hob, are working correctly.

Parts commonly replaced

  • Ignition Electrode
  • Gas Valve
  • Ignition PCB
Full explanation for F1
F2

Your boiler is lighting the fire, but it cannot detect that the flame is there, so it is shutting down for safety.

High Engineer only £90-180

Parts commonly replaced

  • Ionisation electrode
  • Ignition/Sensing cable
  • Printed Circuit Board (PCB)

Related codes

Full explanation for F2
F3

Your boiler has switched itself off because it has reached an unsafe temperature, usually due to the water inside not moving around properly.

High DIY-safe £120-280

What to check first

  1. Check that your home's radiator valves are fully open.
  2. Ensure your boiler's system pressure is between 1 and 1.5 bar on the gauge.
  3. Restart the boiler using the reset button once the system has cooled down.

Parts commonly replaced

  • Overheat Thermostat
  • Circulation Pump
  • Limit Stat

Related codes

Full explanation for F3
F4

Your boiler has stopped working because it cannot safely confirm that waste gases are being cleared through the flue pipe.

High Engineer only £120-£350

Parts commonly replaced

  • Air Pressure Switch
  • Fan Assembly
  • Venturi Tube

Related codes

Full explanation for F4
F5

Your boiler has detected that a safety sensor is stuck, preventing the fan from safely venting exhaust gases and stopping the boiler from firing up.

High Engineer only £120-£250

Parts commonly replaced

  • Air pressure switch
  • Fan
  • Venturi tube

Related codes

Full explanation for F5
F6

Your boiler has lost its ability to measure the temperature of the water heading to your radiators, meaning your heating system will likely stop working for safety.

High Engineer only £90-£160

Parts commonly replaced

  • Central heating flow temperature sensor (NTC thermistor)
  • Sensor wiring harness

Related codes

Full explanation for F6
lockout light

Your boiler has safety-locked itself to prevent damage and simply needs a manual restart to try and fire up again.

High DIY-safe £100-280

What to check first

  1. Locate the main On/Off/Reset selector switch (marked A) on the control panel.
  2. Turn the switch clockwise against the spring tension to the 'Reset' position.
  3. Release the switch and wait for the boiler to attempt the ignition sequence.

Parts commonly replaced

  • Ignition Electrode
  • Gas Valve
  • PCB

Related codes

Full explanation for lockout light
Red lockout light

Your boiler has stopped working for safety reasons and needs a manual restart to try and restore heating and hot water.

High DIY-safe £100-350

What to check first

  1. Locate the selector switch (marked A) on the control panel
  2. Turn the switch to the 'RESET' position for approximately 2 to 3 seconds
  3. Turn the switch back to its original 'ON' position (summer or winter mode) and wait for the boiler to ignite

Parts commonly replaced

  • Ignition Electrode
  • Gas Valve
  • Overheat Thermostat
  • Printed Circuit Board (PCB)
Full explanation for Red lockout light