Boiler Fault Codes…

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What they mean and how to fix them…

Once you have had a new boiler installed, chances are you probably won’t take much notice of your boiler until the time comes when you realize that you have no heating or hot water! After realizing that your boiler is not working and is showing a strange code on it’s display, it is usually nothing to worry about. Your boiler has a number of components within it, such as it’s Printed Circuit Board (PCB), circulating pump, fan, to name a few. When one of these components is not working correctly, the boiler will shut down to protect itself. At this point, it will display various codes.

The most common codes that we are faced with, relate to there not being enough pressure in the heating system, faults relating to the boiler over-heating and there not being any gas getting to the boiler!

What should you do if your boiler has locked out and displaying a fault code?

The first thing you should do if your boiler has locked out, is to check that there is enough pressure in your heating system. To check this, depending which boiler you, there will be a pressure gauge either on the boiler or just below it. On newer Vaillant boilers, the gauges are part of the LCD screen on the front of the boiler and is displayed on the right-hand side. If you press the top right button twice it will show the system pressure as a  “BAR”. Your pressure should be between 1 and 1.5.

Once you have made sure there is enough pressure in the system, the next thing to do is reset the boiler. On Vaillant boilers, the reset button is a button which shows a flame sign with an “X” across it. If you hold the reset button down for a few seconds, the boiler should clear the fault code and go back into normal operation.

What should you do if your boiler is still locked-out after resetting it?

If your boiler is still locked out after resetting it or begins to start up, but then cuts out it could be that your condense pipe is blocked. This can easily be checked but getting a small bowl and placing it underneath the boiler. Under the boiler you will find a plastic pipe attached to the underside of it. Gently loosen off the pipe and be ready to catch any water that may have back up into your boiler! If your condense is blocked, it could be that it has frozen, or there may be an issue with your waste pipe. Commonly, we attend homes where the kitchen sink has blocked and this causes the boiler condense pipe to also block up and prevent the boiler from working.

What to do if your boiler is still not working?

If after checking your system has pressure, checked that the condense pipe is not blocked and can confirm that there is gas entering the boiler (just turn on your gas hob or oven, if you have one or check that the gas meter has not locked out),  you may need a qualified gas engineer.

In order to help the engineer, he will need to know what the fault code on the boiler is reading (a photo is always great!). He will also need the name of the boiler manufacturer and which model the boiler is. On Vaillant boilers, there is a data badge with this information on it on the underside of the boiler. On other manufacturers, this information may also be underneath or potentially on the front of the boiler, behind the front flap.

We hope this has been of help to you and if you require us to come out and assist you further, please do not hesitate to get in contact today!

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