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Ideal Boiler Fault Codes and Errors

Ideal Boilers are undoubtedly some of the most reliable and efficient appliances out there. This is especially the case where you strictly adhere to annual maintenance appointments. However, once in a while, you will find your boiler flashing error codes on its panel and, in some cases, experience a total boiler lockout.

Usually, poor maintenance of the boiler hastens underlying problems and result in error displays and boiler lockouts.

There is no need to worry though as most boiler lockouts are by design to ensure the error highlighted by the error codes do not cause further damage to your boiler or pose a health risk to your family. As such, most fault codes will clear after a simple reset of your ideal boiler.

But if the problem persists, the best course of action is to contact a registered gas engineer. Tempering with the internal parts of the boiler yourself might fester the problem, and you might end up having to pay hundreds of pounds in repair costs.

You should consider two things upon noticing an error code displayed by your Ideal boiler:

  • If your Ideal boiler is under warranty, having a registered gas engineer fix the error codes will be cheap or even free if your boiler is under contract and kept in good shape.
  • Try resetting your ideal boiler – As earlier mentioned, resetting the boiler solves close to 80% of most error codes.

There are a variety of Ideal boilers for domestic use. Therefore, we have aligned the various boilers with potential errors that you may see on display and how to fix them. If a simple reset does not solve your boiler’s problem, resort to having a Safe Gas registered engineer check out your boiler.

The Ideal boiler models that we’ve covered in this guide include:

  • Ideal Logic Max/ Ideal Logic+ boiler (regular and system)
  • Ideal Logic Max/ Ideal Logic+ Combi boiler
  • Ideal Vogue Gen 2/ Ideal Mexico HE Combi Boiler
  • Ideal Isar/ Icos Combi boiler

How to reset different models of Ideal boilers.

Ideal boiler model How to reset the boiler
Ideal Logic Turn knob to the marked reset position
Ideal Logic plus  Press the ‘reset’ button once
Ideal Vogue Switch off the boiler, set heating controls between 30-80 degrees Celsius, then switch the boiler back on.
Ideal Mexico Press the ‘reset’ button for 2 seconds and release
Ideal Isar Press the ‘reset’ button for 2 seconds and release
Ideal Icos Press the ‘reset’ button for 2 seconds and release
Ideal Mini Press the ‘reset’ button once

Errors displayed by your Ideal boiler will primarily be: F fault codes, L fault codes, C fault codes, or other faults. Here is a list of the various error codes found on the different Ideal boiler models.

Ideal Logic Max/ Ideal Logic+ boiler error codes (system and regular)

Ideal Logic Max and the Ideal Logic plus system boilers are pretty the same, except for a few noticeable differences in guaranteeing. The Ideal Logic max has a 10-year guarantee compared to the 7-year warranty of the Ideal Logic plus since the Ideal Logic max has a high-quality system filter. The Ideal Logic Max and the Ideal Logic plus are both ascending, with both brands having a great range to suit average households.

They are available in four different outputs:

  • Ideal Logic Max/Ideal Logic plus S15:  15KW
  • Ideal Logic Max/ Ideal Logic Plus S18: 18KW
  • Ideal Logic Max/ Ideal Logic plus S24: 24KW
  • Ideal Logic Max/ Ideal Logic plus S30: 30KW
Fault code/error Description How to fix it
F1 fault code Low water pressure Confirm that the system water pressure is between 1 and 1.5 bar on the system pressure gauge. To repressurize the system, you can top up your boiler’s water using the built-in filling loop. Also, check out compare the boiler market advice centre on how to repressurize your boiler.
F2 fault code Flame loss Flame loss may be due to a lack of sufficient gas supply. You should first check the other gas appliances in your home and confirm the gas supply to your house is on. If the gas supply is fine, try resetting your boiler, and if it fails to operate, contact a Gas Safe registered engineer. You can also contact Ideal if you are still under a contract which will save you money.
F3 fault code Fan fault First, reset the boiler. If it fails to operate, the best course of action is to contact Ideal (if the boiler is still under warranty) or get a Gas Safe registered engineer as the causes may vary. Again, costs vary depending on the problem.
F4 or L4 fault code Flow thermistor fault First, reset your boiler. If it fails to operate, the best course of action is to contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer.
F5 or L5 fault code Return thermistor fault First, reset your boiler. If it fails to operate, the best course of action is to contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer.
F6 fault code Outside sensor fault First, reset your boiler. If it fails to operate, the best course of action is to contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer.
F7 fault code Low mains voltage If the voltage is below 190 V, you need to contact your installer. Since it is an electrical problem, you might also need to get an electrician.
F9 or L9 fault code Printed Circuit Board (PCB) fault Contact Ideal (if the boiler is under warranty) or otherwise contact a Gas Safe registered engineer. Repairing costs are high, and therefore replacing your boiler might be the better option.
L1 or FD fault code Flow temperature overheat

 

First, rest your boiler to solve the issue. If it does not work, contact a safe Gas registered engineer. Overheating will generally occur in less efficient and old boilers. Investing in a new boiler will be a good idea.
L2 fault code Ignition Lockout Try resetting the boiler to resolve this issue. Rumbling noises from the system mainly infer that your condensate ducts might have some blockage. Call a Gas Safe registered engineer.
L6 fault code False flame lockout First, reset your boiler. If it fails to operate, the best course of action is to contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer.
LC fault code Too many resets in a short while Turn electrical supply to the boiler off and on intermittently. If the boiler does not work, contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer.
FU fault code Flow/return differential – 50°C First, reset your boiler. If it fails to operate, the best course of action is to contact Ideal (if the boiler is still under warranty). Otherwise, get a qualified Gas engineer.

Ideal Logic Max/ Ideal Logic Plus Combi boiler error code.

Ideal Logic Max and the I deal logic plus system boilers are pretty the same, except for a few noticeable differences in guaranteeing. The Ideal Logic max has a 10-year compared to the 7-year guarantee of the Ideal Logic plus since the Ideal Logic max has a high-quality system filter. Both the Ideal Logic Max and the Ideal Logic plus are ascending, with both brands having a great range to suit average households.

They are available in three different outputs:

  • Ideal Logic Max/Ideal Logic plus C24: This boiler provides an output of 24.2 kW to the heating and 24 kW to the hot water at 9.9 litres of hot water per minute (35 degrees Celsius)
  • Ideal Logic Max/ Ideal Logic Plus C30: This boiler provides an output of 24.2 kW to the heating and 30 kW to the hot water at 12.4 litres of hot water per minute (35 degrees Celsius)
  • Ideal Logic Max/ Ideal Logic plus C35: This boiler provides an output of 24.2 kW to the heating and 35 kW to the hot water at 14.5 litres of hot water per minute (35 degrees Celsius)
Fault Message How to Fix it
   
Outside sensor fault First, reset your boiler. If it fails to operate, the best course of action is to contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer.
Low Mains Voltage If the voltage is below 190 vacs, you need to contact your installer. Since it is an electrical problem, you might also need to get an electrician.
Printed Circuit Board (PCB) fault Contact Ideal (if the boiler is under warranty) or otherwise contact a Gas Safe registered engineer. Repairing costs are high, and therefore it is prudent to replace the boiler altogether.
Too many Resets Turn electrical supply to the boiler off and on intermittently. If the boiler does not work, contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer.
Flames come on before the gas supply is on. First, reset your boiler. If it fails to operate, the best course of action is to contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer.
Low water pressure Dissect that the system water pressure is between 1 and 1.5 bar on the system pressure gauge. To repressurize the system, you can top up your boiler’s water using the built-in filling loop. Also, check out compare the boiler market advice centre on how to repressurize your boiler.
Overheat Lockout First, rest your boiler to solve the issue. If it does not work, contact a safe Gas registered engineer. Overheating will generally occur in less efficient and old boilers. Investing in a new boiler will be a good idea.
Flame Loss Flame loss may be due to a lack of sufficient gas supply. You should first check the other gas appliances in your home and confirm the gas supply to your house is on. If the gas supply is fine, try resetting your boiler, and if it fails to operate, contact a Gas Safe registered engineer. You can also contact Ideal if you are still under contract, which will save you money.
Ignition Lockout Try resetting the boiler to resolve this issue. Rumbling noises from the system mainly infer that your condensate ducts might have some blockage. Call a Gas Safe registered engineer.
Fan fault Reset the boiler. If the boiler fails to operate, contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer as the causes may vary. Also, costs vary depending on the problem.
Flow Thermistor fault First, reset your boiler. If it fails to operate, the best course of action is to contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer.
Return thermistor fault First, reset your boiler. If it fails to operate, the best course of action is to contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer.

Ideal Vogue Gen 2/ Ideal Mexico Combi boiler error codes

Ideal Vogue Gen is made from premium components and comes with a 10-year warranty when registered within 30 days of installation. In addition, it has an A energy efficiency rating, with a rating of 93%. The Ideal Vogue Combi boiler also received the Good Housekeeping Reader Recommended status in 2013 and 2017.

The Ideal Vogue Combi boiler is available in three sizes – 26KW, 32KW and 40KW. It also has built-in frost protection, and therefore the boiler is cold weather safe and won’t seize up if conditions outside are frigid.

The Ideal Mexico Combi boiler by design fits in an appliance space in a kitchen or utility room. It has frost protection, and you can install it in less insulated rooms. They are easy to use as they have a digital display and an optional remote user kit. The Ideal Mexico Combi boiler comes with a 2-year parts labour warranty and has an efficiency rating of 88%. They come in five different sizes – 15, 18, 24, 30 and 36 KW.

Fault code Description How to fix it
F1 Low water pressure Dissect that the system water pressure is between 1 and 1.5 bar on the system pressure gauge. To repressurize the system, you can top up your boiler’s water using the built-in filling loop. Also, check out compare the boiler market advice centre on how to repressurize your boiler.
F2 Flame loss Flame loss may be due to a lack of sufficient gas supply. You should first check the other gas appliances in your home and confirm the gas supply to your house is on. If the gas supply is fine, try resetting your boiler, and if it fails to operate, contact a Gas Safe registered engineer. You can also contact Ideal if you are still under contract, which will save you money.
F3 Fan fault Reset the boiler. If the boiler fails to operate, contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer as the causes may vary. Also, costs vary depending on the problem.
F4 or L4 Flow thermistor fault First, reset your boiler. If it fails to operate, the best course of action is to contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer.
F5 or L5 Return thermistor fault First, reset your boiler. If it fails to operate, the best course of action is to contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer.
F6 Outside sensor fault First, reset your boiler. If it fails to operate, the best course of action is to contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer.
F7 Low mains voltage If the voltage is below 190 vacs, you need to contact your installer. Since it is an electrical problem, you might also need to get an electrician.
F9 or L9 Printed Circuit Board (PCB) fault Contact Ideal (if the boiler is under warranty) or otherwise contact a Gas Safe registered engineer. Repairing costs are high, and therefore it is prudent to replace the boiler altogether.
L1 or FD Flow temperature overheats or no water flow. First, rest your boiler to solve the issue. If it does not work, contact a safe Gas registered engineer. Overheating will generally occur in less efficient and old boilers. Investing in a new boiler will be a good idea.
L2 Ignition Lockout Try resetting the boiler to resolve this issue. Rumbling noises from the system mainly infer that your condensate ducts might have some blockage. Call a Gas Safe registered engineer.
L6 False flame lockout First, reset your boiler. If it fails to operate, the best course of action is to contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer.
LC Too many resets in a short while Turn electrical supply to the boiler off and on intermittently. If the boiler does not work, contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer.
FU Flow/return differential – 50°C First, reset your boiler. If it fails to operate, the best course of action is to contact Ideal (if the boiler is still under warranty). Otherwise, get a Gas Safe registered engineer.

Ideal Isar/ Icos Combi boiler error codes

The Ideal Isar and Ideal Icos Combi boilers are a government scheme that ensures vulnerable families and those from humble backgrounds are provided with cheap affordable boilers. They, therefore, needed to be massed produced, but they, unfortunately, proved inefficient and problematic.

Fault code Description How to fix it
L-F fault code The boiler has failed to ignite Press the ‘reset’ button and hold for two seconds. If the boiler does not reignite, you should check other gas appliances to ensure a gas supply.
L-A fault code Boiler overheated Ensure there is sufficient water pressure in the system and bleed all radiators. Then press and hold the ‘reset’ button for two seconds. The boiler should reignite.
H-3 fault code Domestic hot water thermistor error Press and hold the ‘reset’ button for two seconds
No display No heating or hot water It is implicating a Public Circuit Board failure (PCB). Contact a qualified gas engineer. 

Common faults

Fault Description
No display You can fix a blank boiler display by ensuring that the main supply of the boiler is on.
Noisy operation An Ideal boiler works efficiently in silence; therefore, kettling noises indicate loose components or high pressure. Try repressuring the boiler or check for loose parts. If the boiler fails to operate, get help from a repair team.
High energy bills High energy bills may be due to increased energy usage or even an inefficient boiler. If the latter is the problem, invest in a new boiler.
Fault code 0 0 on display usually mean that the boiler is on standby awaiting a request for hot water or central heating.
Fault code 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.
Fault code 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.
Fault code F The boiler is operating in frost mode.
CO BCC (boiler chip card) activation fault.
C2 BCC (boiler chip card) fault.

Summary

By now, you are knowledgeable of the various error codes. If you notice your boiler display a fault code, know that your boiler needs agent attention. Depending on the type of error displayed, you can discern whether to fix it yourself or have a qualified gas engineer take a look.

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