Ideal boilers are known for their reliability and efficiency, making them a popular choice for homeowners across the UK. However, like all appliances, they can occasionally experience faults. When this happens, Ideal boilers display error codes that help diagnose the problem quickly.Understanding these codes can save you time and money by allowing you to troubleshoot issues or communicate more effectively with a professional engineer.
This guide provides an overview of the most common Ideal boiler faults, from low boiler pressure to ignition faults, to help you identify and address any issues you might encounter.
Common Ideal boiler error codes
Ideal boiler error codes by model
Ideal Logic Max System / Logic Plus System Boiler error codes
Ideal Logic Max / Logic Plus Regular Boiler error codes
Ideal Logic Max Plus Combi Boiler faults
Ideal Vogue Boiler fault codes
Ideal Boiler error descriptions
When to call in a JustFix professional
Common Ideal boiler error codes
|
Fault Code |
System Behaviour |
|
C0 |
Boiler chip card (BCC) activation fault |
|
C2 |
Boiler chip card (BCC) fault |
|
F1 |
Low water pressure |
|
F2 |
Flame loss |
|
F3 |
Fan fault |
|
F4 |
Flow thermistor fault |
|
F5 |
Return thermistor fault |
|
F6 |
Outside sensor failure |
|
F7 |
Low mains voltage |
|
F9 |
Unconfigured printed circuit board (PCB) |
|
L1 |
Flow temperature overheat or no water flow |
|
L2 |
Flame loss |
|
L5 |
5 boiler resets in 15 minutes |
|
L6 |
False flame lockout |
|
0 |
The boiler is in standby mode, awaiting either a central heating or hot water demand |
|
C |
The boiler has a call for central heating but has reached the set temperature or is operating in central heating mode |
|
D |
The boiler has a call for hot water but has reached the set temperature |
|
d |
The boiler is operating in hot water mode |
|
F |
The boiler is operating in frost mode |
Ideal boiler error codes by model
Ideal Logic Max System / Logic Plus System Boiler error codes
The Ideal Logic Max and Logic Plus System boilers are designed for reliability and performance. However, like any boiler, they can encounter issues that trigger error codes. Here are the key fault codes for these models:
|
Error Code |
System Behaviour |
|
L1 |
Flow temperature overheat lockout or no water flow lockout |
|
L2 |
Ignition lockout |
|
LC |
Turn power off and on |
|
L6 |
False flame lockout |
|
F1 |
Low water pressure |
|
F2, FN or LN |
Flame loss |
|
F3 |
Fan fault |
|
L4 or F4 |
Control / no flow thermistor fault |
|
L5 or F5 |
Return thermistor fault |
|
F6 |
Outside sensor fault |
|
F7 |
Low mains voltage. Contact electricity provider. |
|
F9, L9, F8 or L8 |
Printed circuit board (PCB) unconfigured or fault |
|
FU |
Diff greater than 50°C - check isolation valves are open |
Ideal Logic Max / Logic Plus Regular Boiler error codes
The Ideal Logic Max and Logic Plus Regular boilers can also encounter certain faults. Here’s a list of common error codes:
|
Fault Description |
System Behaviour |
|
L1 |
Flow temperature overheat lockout or no water flow lockout |
|
L2 |
Ignition lockout |
|
LC |
5 restarts within 15 minutes |
|
L6 |
False flame lockout |
|
FA |
Flow return reversed |
|
FD |
No water flow |
|
F2 or FN or LN |
Flame loss |
|
F3 |
Fan fault |
|
L4 or F4 |
Control / no flow thermistor fault |
|
L5 or F5 |
Return thermistor fault |
|
F6 |
Outside sensor fault |
|
F7 |
Low mains voltage. Contact electricity provider. |
|
F9, L9, F8 or L8 |
Printed circuit board (PCB) unconfigured or fault |
|
FU |
Diff greater than 50°C - check isolation valves are open |
Ideal Logic Max Plus Combi Boiler faults
The Ideal Logic Max Plus Combi boiler is a high-efficiency model that may have the following faults:
|
Fault Description |
System Behaviour |
|
Overheat lockout |
Bleed radiators, refill system to 1.0 bar, check that radiator and boiler valves are open. Reset boiler. If fault continues, book an engineer. |
|
Ignition lockout |
Check gas appliances work and restart boiler. |
|
Too many restarts |
5 starts within 15 minutes. Turn power on and off. |
|
Flame on before gas on |
False flame lockout |
|
Water pressure |
With boiler off and system cold, fill system to 1.0 bar and bleed radiators. If fault continues, contact an installer. |
Ideal Vogue Boiler fault codes
The Ideal Vogue boiler is another robust model, though it too can encounter errors. Here are some key fault codes:
|
Fault Description |
System Behaviour |
|
Too many resets |
5 restarts within 15 minutes |
|
Flame on before gas valve on |
Flame on before gas valve is on |
|
Flow thermistor fault |
Flow thermistor error |
|
Low mains voltage |
Less than 185V to boiler. Check voltage at boiler mains input. If mains voltage is okay, the pump needs replacing. |
|
Low water pressure |
Low water pressure |
|
Flow return reversed |
Check if the flow thermistor is correctly clipped to pipe. Replace if necessary. |
|
Printed circuit board (PCB) recently replaced |
Reset boiler |
|
Pump rotor blocked |
Unblock pump |
|
Flow temperature set point cannot be increased to 80°C |
Check flow and return thermistors are securely clamped to pipes. |
Ideal Boiler error descriptions
In addition to specific model faults, some general issues can occur across multiple Ideal boiler models. Here are a few more common error descriptions:
|
Fault Description |
Cause |
|
Thermal fuse lockout |
Reset the boiler. |
|
Too many boiler resets |
5 resets within 15 minutes. Turn power off and on. |
|
Printed circuit board (PCB) replaced incorrectly |
Ensure the boiler chip card (BCC) is fitted correctly. |
|
Low mains voltage |
Less than 160V to the boiler. Contact the electricity provider. |
|
Low water pressure |
Increase system pressure to 1.5 bar. |
|
Flow/Return reversed |
Check if the flow thermistor is correctly clipped to the pipe. Replace the flow thermistor if necessary. |
|
Pump rotor blocked |
Unblock the pump. |
|
Flow temperature set point cannot be increased to 80°C |
Ensure the flow temperature is not limited within installer mode. |
|
Pump runs during the night |
Ensure the system frost protection temperature set point isn’t set too high. |
|
Gas pressure < 18mBar |
Check the gas supply and rectify the fault. |
|
No connection to primary printed circuit board (PCB) |
Unblock the pump. |
|
Flame loss |
Check the detection electrode and associated harness for continuity, visual condition, and position. Check if the condensate pipe is blocked. |
|
Printed circuit board (PCB) replaced |
Reset the boiler. |
When to call in a JustFix professional
While some boiler error codes can be resolved with basic troubleshooting, there are times when it’s essential to call in a professional. If you’ve attempted to fix an error code but it keeps reappearing, or if the issue involves critical components like the gas valve, flue gas temperature, or safety switches, it’s time to contact a Gas Safe registered engineer at JustFix.
At JustFix, we’re committed to delivering expert service at competitive prices. Whether you’re facing persistent error codes, suspect a fault in the primary heat exchanger, or simply want the assurance of professional intervention, our nationwide team of skilled engineers is ready to help.
Book online, and we’ll connect you with a qualified local expert who can accurately diagnose and resolve your boiler faults—restoring your heating system’s performance at a time that suits you.
For more guidance on other common issues, explore our blog, where we cover topics such as boiler efficiency ratings and why your boiler is making a banging noise.
