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Ideal Boiler FD Fault Code


The Ideal fault code FD no water pressure Q & A or require an engineer for an emergency boiler repair.


The Ideal Boiler Fault Code FD Error Common Q & A


Just below, we have a list of common questions relating to the FD fault code on the Ideal boiler.

Ideal Boiler FD Fault Code
  • What does the FD fault code mean on my Ideal boiler?
  • Is a boiler with no water flow dangerous?
  • Am I likely to need a new boiler if the FD fault code is being displayed?
  • Can I fix the Ideal boiler FD fault code on a DIY basis?
  • My pressure is below 1.3 bar, what do I need to do next?
  • I topped up my boiler, it started losing pressure and now the FD fault code is showing again?
  • Where could leaks in my heating system be coming from?
  • What could cause a circulation problem on my Ideal boiler?
  • What is heating sludge and how would that affect the pump?
  • Can the pump be cleaned out, or will it need replacing?
  • Is there anything I can do to stop sludge blocking up the heating pump again?
  • How will the boiler engineer know if my heating pump is installed correctly?
  • What damage or wear will my repair engineer look out for on the pump?
  • The Gas Safe engineer thinks this could be a wiring issue, is this right?
  • My engineer thinks my heating pump needs replacing, how much is this likely to cost?

What does the FD fault code mean on my Ideal boiler


The FD fault code on Ideal boilers relates to “no water flow”.

The fault could be with:

  • Lack of water in the central heating system and boiler
  • Problems with parts that work together to circulate water (and monitor that circulation

Is a boiler with no water flow dangerous


Boiler’s with no water flow aren’t dangerous. It’s gas related faults that usually lead to a boiler being unsafe.

However, your appliance should stop working (lock out) to protect components in the boiler.

If there’s no water flow, there’s a good chance that there’s a lack of water in the system. And, when there’s a lack of water in the system, parts such as the heat exchanger can easily overheat.

The boiler locks out these components to protect you from expensive repair bills.

Am I likely to need a new boiler if the FD fault code is being displayed


The good news is that Ideal boilers showing the FD fault code are unlikely to need replacing, and some fixes are incredibly cheap.

Can I fix the Ideal boiler FD fault code on a DIY basis


Unlike most common boiler problems, the Ideal FD fault code can sometimes be fixed on a DIY basis.

The first thing you need to do is check that your boiler has pressure.

There’s a pressure gauge on the front of your boiler, which should be reading around 1.3 bar.

The pressure in your boiler is directly related to how much water is in the heating system. So, as you increase pressure, it increases the amount of water in the system.

My pressure is below 1.3 bar, what do I need to do next


If your boiler is running around 1 bar, it’s unlikely that pressure is the problem, however, it should be adjusted to 1.3 bar.

If your boiler is well below 1.3 bar, it’s likely that there’s a lack of water (and therefore, pressure) in the system.

Underneath your boiler, you’ll need to locate the external filling loop. This is a braided hose, and this is what you need to use to top up water in your boiler.

As you open the boiler’s external filling loop valve, you’ll see pressure start to climb. Stop when you get to 1.3 bar.

If lack of water is causing the FD fault code to be displayed on your Ideal boiler, this will fix the problem.

I topped up my boiler, it started losing pressure and now the FD fault code is showing again


If you’ve topped up your boiler, it cleared the fault code and now it’s showing again, there’s a good chance your losing pressure (and water) from your heating system. And, that means that somewhere you have a leak.

It’s not wise to keep topping up your boiler if this is the case. That water is going somewhere, and it could be causing damage to your property.

The best thing to do is speak to an emergency boiler repair engineer and have them find the leak on your heating system.

Where could leaks in my heating system be coming from


Leaks can come from something simple such as a copper joint, or something more complex such as the seals on the pump.

The problem with leaks is the damage they can cause, rather than the leak itself.

For instance, we’ve seen a leaking pump cause so much internal boiler damage, that the boiler needed to be replaced. And, that’s because it can leak onto expensive boiler components such as the printed circuit board (PCB).

Something like the PCB can cost over £500 to fix.

So, the boiler engineer will need to check everything from pipework to radiators and all internal parts to ensure that all leaks are fixed, before topping up your boiler and resetting it to clear the FD fault code.

What could cause a circulation problem on my Ideal boiler


If you’ve checked your boiler pressure, topped it up to the correct level (1.3 bar) and you now have no leaks; the next step is call a boiler repair engineer.

They’ll need to check the pump, as that’s the most likely reason that water isn’t circulating around the heating system.

The boiler engineer will check:

  • For heating sludge build up
  • That the pump is installed correctly
  • For excessive wear and damage

What is heating sludge and how would that affect the pump


Heating sludge comes from rust that breaks off the inside of radiators, towel rails and even pipe work. It’s also formed from minerals that are in the water circulating around your heating system.

Usually, this will break down and just form dirty water. However, over time this dirty water can form a thick sludge which starts to clog up components.

More importantly, the bits of rust that don’t break down are going to get lodged in your heating system, and your boiler.

These bits of rust can slowly start to block up expensive boiler components, including the pump. If the pump is blocked with bits of debris, that’s going to restrict its ability to circulate water.

Eventually, it’s going to block the heating pump completely and that’s going to lead to the no water flow fault (FD).

Can the pump be cleaned out, or will it need replacing


If the pump isn’t showing signs of excessive wear or damage, your boiler engineer will be able to clean out the pump.

Once the pump is cleaned of all debris, it can be refitted, and this should clear the FD fault code on your Ideal boiler.

Is there anything I can do to stop sludge blocking up the heating pump again


It’s not just the heating pump you need to be worried about. Sludge can block other expensive boiler parts (such as the heat exchanger), not to mention radiators to a point where they simply won’t work anymore.

The best thing to do is to ask your boiler engineer to hot flush the system with chemicals. This hot flush will get rid of most heating sludge that is circulating in your heating system.

Once they’ve done this, they’ll be able to fit a magnetic system filter, which is designed to catch any heating sludge that might break off and circulate in the future.

And finally, they’ll dose your heating system with central heating inhibitor. This breaks down the sludge to a point where the filter can catch it.

How will the boiler engineer know if my heating pump is installed correctly


After inspecting the pump, it will become obvious if it’s not been installed correctly. The shaft needs to be horizontal. If it’s not, the pump will be restricted in terms of circulation, and the pump’s shaft and bearings will wear out much quicker than they should.

Once the boiler engineer has reinstalled the pump, they’ll be able to bleed it of air. These air locks can sometimes contribute to circulation faults such as the FD one you’re currently seeing.

What damage or wear will my repair engineer look out for on the pump


If your pump is old, or has been installed incorrectly, there’s a chance that the shaft and bearings have worn out. If this is the case, you’ll have noticed the pump becoming noisier over time. And, it will also run much hotter than it should.

Many pump manufacturers produce servicing kits that can be used to recondition the pump. However, while a boiler engineer is there, it makes much more sense to have a replacement pump fitted instead.

The Gas Safe engineer thinks this could be a wiring issue, is this right


If your Gas Safe engineer has been fault finding and found it’s an electrical issue, they’ll likely check the flow sensor on your boiler first. If this is faulty, replacements are available.

But, since boilers vibrate, the fix could be as simple as securing connections and wiring from the PCB to the pump. If these connections are loose, it’s going to make the pump work intermittently, or not at all.

And, if it’s excessive vibrations that have caused the fault, the culprit parts need to be found and fixed. Typically, it’s either the pump or fan that’s excessively worn (and vibrating more than normal).

So, they’re the parts your boiler engineer is likely to inspect first.

My engineer thinks my heating pump needs replacing, how much is this likely to cost


The cost will vary. The biggest differential in cost comes from the type of pump you need. The larger the pump, the more expensive it’s going to be.

However, you should expect to budget around £250 to replace your pump, and the job will take an engineer around 1 working day to complete.

Other Ideal boiler issues


For more boiler issues regarding the Idea Boiler then please visit the Ideal Boiler Problems And Cures page.