Common Ideal boilers fault codes

In this guide, we are going to highlight the most common Ideal boilers fault codes that can show up on your boiler and explain what they mean so you can solve issues yourself at home.

Things to Consider if you have a Ideal Boilers fault code:

Before you begin to stress and worry about being out of pocket when a code appears on your Ideal boiler, there are three things you should consider first:

Is Your Boiler Still Covered?

Ideal Boilers is renowned for having long warranties on their boilers, so the first thing to do whenever an issue arises is to check whether you are still covered.

In some cases, your boiler might be backed by a twelve-year warranty which can make it cheaper to have any issues resolved by a professional.

Check your warranty length by contacting ideal boilers direct

Have You Reset The Boiler?

We have all heard the classic ‘turn it off and on again’ as a solution for when things go wrong, but there is some truth behind the cliché.

In some cases, an error code might show even if there is not a mechanical problem so to save yourself time and effort try turning the device off to see whether it goes away.

If the error code appears once the boiler has rebooted, it is time to look further into it.

Have you checked the pressure?

Low pressure is a sign that there isnt enough water in your system, Check for leaks and top up using the filling loop. This can be located on your boiler or externally underneath your boiler. Occasionally it is located else where around the house. Consult your installation instructions on advice on how to do this.

F1: Low water pressure

The problem
If your heating system doesn’t have enough water, this fault can occur as its pressure could become low. It is usually possible for you to fix this issue yourself by topping up your boiler’s water pressure to 1.5 using the in-built in filling loop. If you’re still facing issues, contact a Gas Safe registered engineer.

Ideal boilers fault codes F2: Flame loss

The problem
This usually means that there has been a flame loss during operation. This issue could be caused by deeper system errors such as incorrect gas pressure, an issue with your flue, a faulty gas valve, an incorrect adjustment of a valve or a fan fault. Firstly, check other gas appliances and you could try to reset your boiler. This fault typically occurs with older boilers and low-efficiency systems.

Ideal boilers fault codes F3: Fault with fan

The problem
This fault is caused by a loose or damaged fan. This issue could be related to deeper problems such as loose or damaged connections, water damage from a boiler leak, a fault with the air pressure switch or a problem with the printed circuit board.

Ideal boilers fault codes F4: Thermistor fault

The problem
The F4 Ideal boilers fault code tends to signify a problem with your boiler’s flow thermistor or an issue with its operation. The fault will typically be related to circulation issues.

Ideal boilers fault codes F5: Return thermistor fault

The problem
This refers to a fault in the return thermistor or its operation. related to a faulty NTC return thermistor, a damaged connection, a differential in temperature that’s too high between the flow/return thermistors, or a faulty printed circuit board.

Ideal boilers fault codes F7: Low mains voltage

The problem
If you notice this Ideal boilers fault code, there could be an issue with your property’s mains electricity source. As a safety precaution, your boiler is built to cease operations once it identifies this fault.

Ideal boilers fault codes F9: Printed circuit board (PCB) fault

The problem
The F9 Ideal boilers fault code on your Ideal boiler typically relates to an unconfigured printed circuit board (PCB).

Ideal boilers fault codes L1: Lack of water flow

The problem
Your boiler takes resistance readings which are then sent to the printed circuit board and if the temperature reading is too low or too high, the boiler will cease to work as a safety precaution and display a Ideal boilers fault code. Check your system pressure and top up as neccesary

L2: Ignition lockout

The problem
Your boiler has ‘locked out’ as a safety precaution. The cause behind this will need to be identified. Reset your boiler. If there’s rumbling coming from the system, this suggests your condensate pipe is blocked or that there is an issue with your flue. Check other appliances to ensure you dont have a gas supply issue.

L9/H9/HA/LA: Overheating

The problem
Like L1, this Ideal boilers fault code could indicate that the temperature on your resistance reading is too high. Check your system’s pressure reading, you could also bleed your radiators to see if this helps.

LF: Ignition fault

The problem
Your boiler may have ‘locked out’ as a safety precaution. The cause of this will need to be addressed. Check that other gas appliances in your home are working, if so, we recommend that you then reset your boiler. If your boiler is rumbling, there could be a blockage in your condensate pipe. Contact a qualified engineer to fix the issue.

No display

The problem
There is an issue with your printed circuit board.

Noisy operation

The problem
Issues such as kettling tend to be common issues with central heating systems. A humming or rattling noise could indicate issues such as loose components or high pressure.

Noisy ignition

The problem
This could indicate a problem with your system’s condensate pipe, gas or flue.

No/poor hot water

The problem
If your heating is working but your hot-water is not being delivered as usual, it typically won’t be a fault with the boiler.

No/poor central heating

The problem
If your DHW is okay, this is not typically a fault with the boiler, but instead a problem with your radiators..

Pressure loss

The problem
This usually means that water is escaping somewhere in the system, or alternatively the issue could be due to the expansion valve failing and thus causing damage to the pressure release valve.

Sometimes, Ideal boiler fault codes indicate a small problem that can be solved at home. However, it is always a good idea to get an engineer to check your handywork.

Common Ideal boilers fault codes