Boiler faults are a specific problem or malfunction detected by your boiler’s internal computer. When the boiler notices that something isn’t working correctly it will stop running to protect itself and your home.
Boiler fault codes are a boilers way of telling us what has gone wrong. A boiler breakdown can be a massive problem. We rely on our boilers (especially combi boilers) more than we realise for hot water and heating. Luckily boiler fault codes give us a clue about why the heat and hot water aren’t working.
What is a boiler fault code?
The boiler follows a set sequence of operations as it runs. A rough example may be like this:
- The boiler checks the water pressure
- The boiler runs the pump and checks the water is moving.
- Checks the temperatures in the boiler.
- Runs the fan and checks it is spinning fast enough.
- Opens the gas valve and tries to ignite the gas.
- Checks to see if the gas has ignited.
As it goes through its sequence it is looking for readings from sensors that fit with its expectations. If the readings are as expected the boiler carries on. If they aren’t as expected the boiler stops and displays a fault code.
Boiler faults can be annoying but they are designed to keep you and your family safe. They inform you of potential problems and avoid unnecessary damage to the boiler.
What does a fault code look like?
Most modern boilers have a digital display which can show a series of digits to indicate the fault type.
Boilers display faults in different ways depending on the age and manufacturer.
- Flashing lights in a particular sequence.
- Letters and numbers displayed on a screen
- Push buttons popping out on thermostats
Boilers that don’t have a digital display use a series of lights that flash in a sequence or have an on or off pattern that shows the fault.
Each manufacturer has its own set of fault codes. Some are shared between models others are specific to that particular model.
What should I do with my boiler fault code?
Your boiler is displaying a fault. What should you do now? You must record your boiler fault code for any future heating engineer visit.
The best way to do this is by taking a short video. Record any flashing lights or symbols on the display.
For some boilers once you reset the fault it is gone and there is no record of it.
Some boilers have a fault memory that can be accessed after resetting.
My boiler is broken but there is no fault code
This type of fault comes when the sequence of operation isn’t broken but the boiler still doesn’t go to a fault.
If there is a problem with controls or the plumbing side of your central heating the boiler won’t know about it so won’t develop a fault.
If the fault isn’t quite serious enough (yet) to break the sequence of operations then there will be no fault code. This type of fault needs a different type of fault finding.
If the fault is on the control board (PCB) it may not develop a fault but still not work.
Click here for more advice on faults that don’t show a fault code.
What does my fault code mean?
Each manufacturer has a list of fault codes for their boilers. The faults codes can change over time as new models are produced.
Most popular brands of boiler and their fault codes:
- Worcester Bosch Fault Codes
- Ideal Fault Codes
- Alpha Fault Codes
- Vaillant Fault Codes
- Viessman Fault Codes
- Glow Worm Fault Codes
To find that out you will need to find your make and model of boiler then either look in this website or find the manual for your boiler.
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e160-fault-on-a-baxi-or-potterton-boiler
f1-low-pressure-fault-on-an-ideal-logic-boiler
e119-fault-on-baxi-or-potterton-boiler
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low-pressure-on-a-Worcester-boiler
F75-fault-on-a-Vaillant-boiler
If you found this confusing:
If you found this confusing. Please let us know in the comments section so we can clear things up for you. We love feedback and we are trying to make the best possible website. If you don’t understand then others don’t as well.
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