Ideal Boiler Issues: Errors and Fault Codes

Ideal boilers tend to be fairly reliable appliances but they can still develop faults when they’re not properly maintained. Having said that, things can go wrong with your Ideal boiler even if you do take good care of it year after year. When a fault occurs, your boiler should display a fault code or fault message to help you and your engineer diagnose the problem. Your Ideal boiler may even go into a lockout mode (a shut-down procedure) and remain this way until the fault is fixed and the code is cleared.

If a fault code or fault message has appeared on your Ideal boiler and you want to know what it means, you should be able to find the answer you’re looking for by scrolling through the tables below.

Ideal Logic Max System and Logic+ System Boiler Fault Codes

FAULT CODE DESCRIPTION / ACTION REQUIRED
F1 Low water pressure. Check the system water pressure is between 1 and 1.5 bar on the system pressure gauge. To re-pressurise the system, see section 3 of user manual. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
F2 Flame loss. Check the other gas appliances in the house are working to confirm gas supply is present in the property. If the other appliances don’t work or there are no other appliances to try, check the gas supply is on at the meter and/or pre-payment meter has credit. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
F3 Fan fault. Restart the boiler. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
F4 or L4 Flow thermistor fault. Restart the boiler. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
F5 or L5 Return thermistor fault. Restart the boiler. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
F6 Outside sensor failure. Restart the boiler. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
F7 Low mains voltage. Contact your electricity provider or a qualified electrician.
F9 or L9 Unconfigured PCB. Contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
L1 Flow temperature overheat or no water flow. Check the system water pressure is between 1 and 1.5 bar on the system pressure gauge. To re-pressurise the system, see section 4 of user manual. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
L2 Ignition lockout. Check the condensate pipe for blockages (see section 3 of manual). Check the other gas appliances in the house are working to confirm gas supply is present in the property. If the other appliances don’t work or there are no other appliances to try, check the gas supply is on at the meter and/or pre-payment meter has credit. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
L6 False flame lockout. Restart the boiler. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
LC 5 boiler resets in 15 minutes. Turn electrical supply to boiler off and on. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
FU Flow/return differential – 50°C. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).

Ideal Logic Max Heat and Logic+ Heat Boiler Fault Codes

FAULT CODE DESCRIPTION / ACTION REQUIRED
F2 Flame loss. Check the other gas appliances in the house are working to confirm gas supply is present in the property. If the other appliances don’t work or there are no other appliances to try, check the gas supply is on at the meter and/or pre-payment meter has credit. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
F3 Fan fault. Restart the boiler. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
F4 or L4 Flow thermistor fault. Restart the boiler. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
F5 or L5 Return thermistor fault. Restart the boiler. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
F6 Outside sensor failure. Restart the boiler. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
F7 Low mains voltage. Contact your electricity provider or a qualified electrician.
F9, L9, F8 or L8 Unconfigured PCB or gas valve short circuit. Contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
FA Flow/Return reversed. Contact a Gas Safe registered engineer. In IE, contact a Registered Gas Installer (RGII).
Fd No water flow. Contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
L1 Flow temperature overheat or no water flow. Check the system water pressure is between 1 and 1.5 bar on the system pressure gauge. To re-pressurise the system, see section 4 of user manual. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
L2 Ignition lockout. Check the condensate pipe for blockages (see section 3 of manual). Check the other gas appliances in the house are working to confirm gas supply is present in the property. If the other appliances don’t work or there are no other appliances to try, check the gas supply is on at the meter and/or pre-payment meter has credit. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
L6 False flame lockout. Restart the boiler. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
LC 5 boiler resets in 15 minutes. Turn electrical supply to boiler off and on. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
FU Flow/return differential – 50°C. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).

Ideal Logic Max Combi and Logic+ Combi Boiler Fault Messages

FAULT MESSAGE DESCRIPTION / ACTION REQUIRED
Outside sensor fault. Contact installer. Restart the boiler. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
Low mains voltage. Contact electricity provider. Contact your electricity provider or a qualified electrician.
PCB fault. Contact installer. Unfigured PCB. Contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
Too many resets. Contact installer. Turn the power off and on at the fused supr. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
Flame on before gas on. Contact installer. Restart the boiler. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
Water pressure 1/3. With Boiler off and system cold, fill system to 1.0 bar.   Water pressure 2/3. Bleed radiators and refill system to 1.0 bar.   Water pressure 3/3. If fault persists, contact installer. Check that the system pressure is between 1 and 1.5 bar on the pressure gauge. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
Overheat lockout 1/4. With boiler off and system cold, fill system to 1.0 bar.   Overheat lockout 2/4. Bleed radiators and refill system to 1.0 bar.   Overheat lockout 3/4. Check radiator valves and boiler valves are open.   Overheat lockout 4/4. Restart boiler. If the fault persists, contact installer. Check that the system pressure is between 1 and 1.5 bar on the pressure gauge. Restart the appliance. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
Flame loss. Contact installer. Check the other gas appliances in the house are working to confirm gas supply is present in the property. If the other appliances don’t work or there are no other appliances to try, check the gas supply is on at the meter and/or pre-payment meter has credit. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
Ignition lockout 1/2. Check other gas appliances are working, then restart the boiler.   Ignition lockout 2/2. If fault persists, contact installer. Check the other gas appliances in the house are working to confirm gas supply is present in the property. If the other appliances don’t work or there are no other appliances to try, check the gas supply is on at the meter and/or pre-payment meter has credit. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
Fan fault. Contact installer. Restart the boiler. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
Flow thermistor fault. Contact installer. Restart the boiler. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).
Return thermistor fault. Contact installer. Restart the boiler. If the boiler fails to operate, contact Ideal (if boiler still under warranty) or alternatively contact a Gas Safe registered engineer (if outside of the warranty period). In IE, contact a Registered Gas Installer (RGII).

Other Ideal Boiler Fault Codes

FAULT CODE DESCRIPTION / POSSIBLE CAUSE
0 The boiler is in standby mode awaiting either hot water demand or a central heating call.
C The boiler is operating in central heating mode or the boiler has a call for central heating and the appliance has reached the desired set temperature.
D The boiler is operating in hot water mode or the boiler has a call for hot water and the appliance has reached the desired set temperature.
F The boiler is operating in frost mode.
C0 BCC (boiler chip card) activation fault.
C2 BCC (boiler chip card) fault.
F1 Boiler pressure too low.
F2 Flame loss.
F3 Fault with fan.
F4 Fault with flow thermistor.
F5 Fault with return thermistor.
F6 Outside sensor failure.
F7 Low mains voltage.
F9 Unconfigured PCB (printed circuit board).
L1 No water flow or flow temperature overheat.
L2 Flame loss.
L5 5 boiler resets in 15 minutes.
L6 False flame lockout.

Ideal Boiler Fault Finding Information for Vogue Max Combi, Vogue Gen2 Combi, Vogue Max System and Vogue Gen2 System

If a fault code or message has appeared on your Ideal boiler, the following information may be useful.

FAULT ACTION REQUIRED
Hot water is fine but no central heating. Rotate the central heating temperature control knob € clockwise. Ensure the timer and the room stat are switched on. Check the batteries in the programmable room stats.
Hot water temperature is too low. Rotate the domestic hot water temperature control knob (F) clockwise. In cold weather, it may be necessary to restrict the flow from the tap to achieve the desired temperature.
Blank boiler display. Ensure the mains supply to the boiler is switched on and make sure that no trips have operated in the consumer unit.
Central heating flow temperature setpoint cannot be increased to 80°C. Ensure that the central heating flow temperature is not limited within the menu (see page 18 of user guide – change settings).
Too many restarts. 5 boiler faults have been reset within a 15-minute period. It is recommended that the boiler should be examined by a qualified service engineer. To clear the message, turn the power off and on.