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Ideal Boiler F1 Fault Code Explained [And How To Fix It]

The F1 fault code on Ideal Boilers is one of the most common error on multiple boiler models, including the Logic combi. And, although many other fault codes end up in a long-winded diagnostic process, as well as an expensive fix, this shouldn’t be the case here.

Our quick guide below covers exactly what the F1 fault code means, and how to fix it. In general, you’ll be able to fix the F1 fault code without help. But, if in doubt, speak to a Gas Safe engineer.

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What Does The F1 Fault Code Mean?

There is a lack of pressure in your heating system. The system’s pressure is determined by the amount of water it contains.

It’s likely you’ll see the code and a flashing light on the front of your boiler. The appliance won’t work again until the pressure issue is fixed, and the boiler is reset.

Causes Of The F1 Fault Code

In the simplest scenarios all that needs to be done, is to add water to the system via the filling loop.

However, if the system pressure is dropping, this indicates there could be a leak. This needs to be fixed before you increase your boiler’s pressure, otherwise your property/boiler could be subject to water damage.

So, we’d suggest flicking through our guide on how to fix the F1 fault code below, before deciding what to do next.

Fixing The F1 Fault Code

Depending on the exact issue, you may need to contact a Gas Safe engineer. This is certainly the case for any step below that requires the boiler to be taken apart.

  1. Test The Pressure Sensor

If your boiler is sitting between 1-2 bar (1.5 bar is ideal), pressure isn’t the problem. However, that isn’t to say your boiler knows that the pressure is correct.

It’s the job of the water pressure sensor to tell the printed circuit board (PCB) whether the pressure is too high or low. If it’s not doing its job and giving the PCB false signals, the boiler won’t work, and the F1 fault code will be displayed.

So, your heating engineer will want to test the water pressure sensor; it might need replacing.

  1. Lack of Pressure, or Pressure Loss?

If the pressure is lacking (i.e. sensor isn’t the issue), you’ll need to determine whether the problem is a lack of pressure, or loss of pressure.

A lack of pressure will require the boiler to be topped up with water via the filling loop (see how to increase boiler pressure below).

However, if the boiler pressure is consistently dropping, that’s a sign of a leak. You’ll want to get the leak fixed before topping up the boiler’s pressure, otherwise you could have expensive repair bills for internal boiler components due to water damage, or even plaster/floorboards if the leak is coming from pipework.

You’d expect a boiler to stay stable at 1.5 bar. Below 0.5 bar it’s going to stop working. So, is the boiler dropping pressure after it’s topped up?

  1. Finding Leaks

Naturally, the next step is to find leaks. Even the smallest leak is going to mean water loss over time, and that means pressure loss too.

Your heating engineer will systematically check things such as:

  • Radiators and towel rails for pinholes
  • Copper pipework for pinholes or loose joints
  • The boiler’s pump and heat exchanger.

In most cases, the leak will be coming from one of the above. It needs to be fixed before increasing your boiler’s pressure.

  1. Increasing Boiler Pressure [And Bleeding Radiators]

The boiler will then need to be topped up, using the small braided hose beneath the boiler casing (the filling loop).

Monitor the pressure gauge as you increase boiler pressure – you’re aiming for around 1.5 bar (always check your owner’s manual to confirm this).

Note: As you fill up your heating system, air will enter. This essentially creates a blockage in your heating system, so it needs to be removed. You’ll need to top up the boiler and bleed radiators at the same time, so it’s worth getting a second pair of hands.

As you bleed them, pressure will drop (so you’ll need to keep topping up via the filling loop) alongside bleeding them, until ALL air has escaped. We’ve created a guide covering how to bleed radiators here.

  1. Clear The F1 Fault Code

So, you’ve found and fixed leaks, increased boiler pressure and bled all radiators.

The final step to clear the F1 fault code and get your boiler up and running again, is to reset your boiler; job done!

Ideal Boiler Problems

The F1 fault code isn’t the only common issue with Ideal Boilers. In most scenarios, multiple error codes will show at once. When they don’t, there’s still a chance that there’s more than one problem.

If your boiler still isn’t fixed, jump over to our guide covering the most common Ideal boiler problems here.

And if you’re fed up of your old boiler and want a new one? Check out our guide to new boiler costs here.

What’s Next?

That’s it! Hopefully that’s got the F1 error code cleared.

Still got issues? Send us an email via our contact page and we’ll do our best to help you out.

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