Updated: 26th March, 2024
The complete guide to what each Ideal boiler error code means and how to fix it!
Is your Ideal boiler not working properly and displaying a strange error code on its screen?
Fear not! In this guide, we will be explaining what each Ideal fault code means and how to fix it.
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Before we get started, it’s worth noting that many of these Ideal boiler error codes can be resolved by resetting your boiler, so it’s important to know how to reset your model.
Take a look at the table below to find out how to reset your Ideal boiler according to the model.
Ideal Boiler Model | How to Do a Boiler Reset |
|---|---|
Ideal Logic | Turn the knob to the ‘reset’ position. |
Single press the ‘reset’ button. | |
Ideal Vogue & Ideal Vogue Max | Turn off the boiler using the On/Off control. Set the heating controls between 30ºC - 80ºC. Turn the boiler back on. |
Ideal Mini | Single press the ‘reset’ button. |
Ideal Mexico HE | Press and hold the ‘reset’ button for 2 seconds and release. |
Ideal Isar | Press and hold the ‘reset’ button for 2 seconds and release. |
Ideal Icos | Press and hold the ‘reset’ button for 2 seconds and release. |
Now let’s jump into what each boiler error code means and how you can fix it.
Fault Code | Issue | How To Fix |
|---|---|---|
F | The boiler is operating in frost mode. | Frost mode turns on when the water in the system has dropped below a specific temperature to prevent it from freezing. This doesn’t require a fix. |
F1 | Low water pressure. | Make sure the system water pressure is between 1 and 1.5 bars on the system pressure gauge. Find out how to re-pressurise your boiler here. |
F2 | Loss of flame. | Check your other gas appliances are working to make sure the gas supply is present in your home. If other appliances aren’t working, ensure your gas supply is turned on at the meter and that any prepaid meters have credit. If it is just your boiler without gas, contact Ideal (if your boiler is still under warranty) or a Gas Safe engineer to come out and take a look. |
F3 | Fault with fan. | Restart your boiler using the guide above. If the issue with the fan persists, contact Ideal (if your boiler is still under warranty) or a Gas Safe engineer to come out and take a look. |
F4 | Fault with flow thermistor. | Restart your boiler using the guide above. If the issue with the flow thermistor persists, contact Ideal (if your boiler is still under warranty) or a Gas Safe engineer to come out and take a look. |
F5/L5/L9 | Fault with return thermistor. | Restart your boiler using the guide above. If the issue with the return thermistor persists, contact Ideal (if your boiler is still under warranty) or a Gas Safe engineer to come out and take a look. |
F6 | Outside temperature sensor failure. | Restart your boiler using the guide above. If the issue with the outside temperature sensor persists, contact Ideal (if your boiler is still under warranty) or a Gas Safe engineer to come out and take a look. |
F7 | Low mains voltage. | Contact your electricity provider or a qualified electrician to take a look. |
F9 | Unconfigured PCB. | Contact Ideal (if your boiler is still under warranty) or a Gas Safe engineer to come out and take a look. |
FD | No water flow. | This is an issue caused by the boiler’s installation. This could be resolved by re-pressurising your boiler, but if this doesn’t help you should contact your installer to rectify the problem. |
FU | Flow/return differential 50ºC. | Contact Ideal (if your boiler is still under warranty) or a Gas Safe engineer to come out and take a look. |
Fault Code | Issue | How To Fix |
|---|---|---|
L1 | Flow temperature overheat / No water flow. | Make sure the system water pressure is between 1 and 1.5 bars on the system pressure gauge. Find out how to re-pressurise your boiler here. |
L2 | Ignition lockout. | Take a look at the condensate pipe and check for any blockages caused by ice or sludge. If it is an ice blockage, simply use a hot water bottle or pour warm (not boiling) water over the pipe itself. If the blockage is caused by sludge, contact Ideal (if your boiler is still under warranty) or a Gas Safe engineer to come out and clean it. |
L3/L4 | No flow thermistor fault. | Restart your boiler using the guide above. If the issue with the return thermistor persists, contact Ideal (if your boiler is still under warranty) or a Gas Safe engineer to come out and take a look. |
L5/F5 | Fault with the return thermistor. | Restart your boiler using the guide above. If the issue with the return thermistor persists, contact Ideal (if your boiler is still under warranty) or a Gas Safe engineer to come out and take a look. |
L6 | Flame detection fault. | Reset your boiler. |
LC | There have been 5 boiler rests in 15 minutes. | Turn the electrical supply to the boiler off and then back on. If the issue persists, contact Ideal (if your boiler is still under warranty) or a Gas Safe engineer to come out and take a look. |
L-F | Boiler is failing to ignite. | Press the reset button for 2 seconds. The boiler will attempt to ignite again. If it still doesn’t work, check the other gas appliances in your home to see if it is an issue with the mains. |
L-A | Boiler overheated. | Make sure your boiler pressure is topped up and bleed any radiators that need bleeding. Then reset your boiler. |
Fault Code | Issue | How to Fix |
|---|---|---|
C | The boiler is operating in central heating mode. | This isn’t a fault and doesn’t require a fix. |
C0 | BCC (boiler chip card) activation fault. | Reset the boiler. If this doesn’t resolve the problem, contact Ideal (if your boiler is still under warranty) or a Gas Safe engineer to come out and take a look. |
C2 | BCC (boiler chip card) fault. | Reset the boiler. If this doesn’t resolve the problem, contact Ideal (if your boiler is still under warranty) or a Gas Safe engineer to come out and take a look. |
Fault Code | Issue | How to Fix |
|---|---|---|
H-3 | Domestic hot water thermistor error. | Reset the boiler. |
0 | The boiler is in standby mode. | This isn’t a fault and doesn’t require a fix. |
D | The boiler is operating in hot water mode. | This isn’t a fault and doesn’t require a fix. |
Have you got a Viessmann, Worcester Bosch or Alpha boiler and aren’t sure what the fault code means? Don’t worry! We’ve also created guides to the most common codes for all of these brands.
Check them out below:
For more advice and guidance when it comes to your home heating, check out our helpful blogs or get in touch with our friendly team at iHeat today!
Ideal boilers, like any brand, can experience several common faults over time, which may include low water pressure, ignition failures, blocked condensate pipe, faulty thermistors, leakage, and error codes. These issues can impact the boiler's performance and require troubleshooting and maintenance to resolve.
The "C" fault code on an Ideal boiler often refers to a specific issue as outlined in your boiler's manual, such as a problem with the combustion. The exact meaning can vary by model, so refer to your user manual for precise troubleshooting and resolution steps. Generally, resolving this may involve checking the gas supply, ensuring proper ventilation, or cleaning the burner. If unsure, it's best to contact a certified engineer.
Flashing "F" and "L" on an Ideal boiler typically indicate a flame loss. This could happen if the boiler attempts to ignite but fails to detect a stable flame. Causes might include gas supply issues, faulty ignition components, or a blocked burner. Consult your boiler's manual for specific guidance and troubleshooting steps.
Clearing an error code on a boiler usually involves identifying the cause of the fault and addressing it. Some boilers reset the error code automatically once the issue is resolved. For others, you might need to manually reset the boiler using a specific button or procedure outlined in the user manual. If the problem persists, professional assistance is recommended.
If your boiler displays a fault code, turning it off can be a safe initial step, especially if you're unsure about the nature of the problem. This can prevent potential damage or unsafe conditions. After turning it off, consult the boiler's manual for the fault code meaning and recommended actions. For significant issues or if in doubt, contact a professional for advice.
An error code on a boiler is a diagnostic tool used by the system to indicate a specific fault or issue within the boiler's operation. These codes are designed to help identify what is wrong, potentially simplifying troubleshooting for technicians or the homeowner. The meaning of each code can vary between boiler models and brands, so it's important to refer to your boiler's manual for an explanation of each code.
Diagnosing a boiler fault typically involves several steps, including checking the error code, referring to the manual, visual inspection, checking basic operational requirements, resetting the boiler, and seeking professional diagnosis if needed. Identifying the specific fault and its cause is essential for effective troubleshooting and repair.
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