How to Fix an F1 Fault Code on an Ideal Boiler

Has your boiler suddenly stopped working and Is displaying an F1 fault code? Don’t panic! In this guide, we will help you understand what the error code means, its common causes, how to troubleshoot it, and when to contact a Gas Safe engineer.

Jump to a topic:

• What does the code mean?
• What causes the error?
  • Water leaks
  • The pressure sensor
  • Recently bled radiators
• Why is low water pressure a problem?
• How to fix an F1 boiler fault code
  • What you will need
  • How to bleed your radiators
• When to call a professional
• Prevention

What does the F1 fault code mean?

The F1 fault code on an Ideal boiler indicates low water pressure in your central heating system. Combi boilers require water pressure to be between 1 and 1.5 bar when cold. If the pressure falls outside of this range, your central heating system will stop working, and the boiler error will be displayed.

This error is particularly common on Ideal Logic Combis.

What causes the fault?

There are several reasons why your boiler may be showing the F1 fault code. Some issues you may be able to repair yourself, while others require professional assistance.

Water Leaks and Loose Joints

Inspect your pipework for damp patches or water traces, as even minor leaks can cause the boiler to lose pressure. If you notice significant water damage, contact a central heating engineer immediately. If you suspect an internal leak within the boiler casing, seek assistance from a central heating leak detection expert.

The Pressure Sensor

The water pressure sensor measures your heating system’s pressure, and a faulty sensor may send incorrect signals to the PCB. An engineer may need to clean or replace this component if it becomes blocked with dirt and debris due to poor maintenance.

Recently Bled Radiators

If you have recently bled your radiators but didn’t top up your central heating system, low water pressure may result. Bleeding radiators releases trapped air, causing pressure to drop. To counter this, ensure you top up your system with water.

Addressing Low Water Pressure Issues

Low water pressure forces your boiler to work harder to circulate water through your heating system, leading to increased energy consumption and costs. Regular maintenance and an annual service can keep such issues at bay, helping maintain an efficient heating system.

How to fix an F1 fault code?

You can often resolve the error code by topping up your central heating system. To do this, follow these steps:

What You Will Need to Bleed Your Radiators

You will need the following:

• Radiator key (available at DIY stores or online)
• Cloth or rag
• Jug or bowl (optional)

How to bleed your radiators

Before bleeding your radiators, it’s helpful to know that if you live in a multi-storey building, you should begin on the ground floor before bleeding upstairs.

1. Turn off your heating and ensure the radiators are cold.
2. Use a radiator key to slowly turn the valve at the top of each radiator, releasing trapped air while catching excess water with a cloth or rag.
3. Retighten the valve when the hissing sound stops.
4. Turn your central heating system back on and check the boiler pressure gauge. If the pressure is too low (below 1 to 1.5 bar), top up the system using the filling loop until the gauge reaches 1 bar. This will increase the boiler pressure.
5. Allow 15-20 minutes for radiators to warm up and ensure they heat correctly.

If your radiators are heating correctly and your boiler pressure is between 1 and 1.5 bar, you have fixed the problem and should no longer see a fault code.

When to contact a professional

If, after bleeding your radiators, you still see the F1 error code, you should get in touch with a trained professional. The engineer will be able to quickly diagnose the issue and recommend ways to prevent the fault in future.

How to prevent a Boiler F1 error

Scheduling regular professional maintenance is the best way to prevent unexpected boiler breakdowns and lockouts. An annual boiler service can help maintain efficiency, prolong your boiler’s lifespan, and save you money in the long run.

More boiler fault codes and useful links:

• Ideal Heating – Support
• Common Boiler Problems and How to Fix Them
• How to fix an F61 error

About the author

Trades Team are experts in Heating, Plumbing and Gas Services. We have 15 years of experience providing expert Boiler Repair and Boiler Servicing to homes and businesses across the Southeast. Learn more about Trades Team.