🕑 9 minutes read

No one wants their boiler to suddenly stop working, especially during the cold winter when we rely on it the most. However, if you have a Baxi boiler and see an E133 boiler fault displayed, don't panic! This fault is common and can be easily fixed with the right knowledge and tools.

This blog will cover the causes of the E133 error code, how to resolve it, and—most importantly—how to keep it from happening again.

What is E133 Boiler Fault?
[Ignition Block]

E133 means the ignition is blocked, and it can happen if there's not enough gas or a problem with the ignition process.

E133 fault code on a Baxi boiler

A Baxi boiler with E133 error code

This E133 boiler fault is a common fault code that appears on Baxi boilers when there is an issue with the gas supply. It indicates that the boiler cannot detect a flame, meaning there is no gas reaching the burner. This can happen for various reasons, but it is usually due to a problem with the gas supply or an issue with the boiler's internal components.

“E133 boiler fault means there's a problem with the gas, ignition, or flame detection in your Baxi boiler.”

What Causes E133 Error Code?

There are several possible causes of the E133 error code.
Some common ones include:

Gas Supply Issue

One common reason for an E133 boiler fault is that the boiler is not receiving any gas, leading to a lockout. You can easily check this without opening up the boiler.

Faulty Gas Valve

The gas does not reach the burner because the inlet valve is closed or faulty.

Frozen Or Blocked Condensate Pipe

Another potential cause for an E133 fault is a blocked or frozen condensate pipe. If the weather is freezing, especially if you have an external condensate pipe, it may freeze, causing the boiler to lock out.

Faulty Boiler Components

An E133 Baxi fault code may also indicate a broken part in the boiler that needs replacement. However, based on our experience, gas supply issues often contribute to this error. So, you need to call a professional for an expert diagnosis and boiler repair.

Faulty PCB (Printed Circuit Board)

There is a lack of continuity in the cable between the control panel and the burner.

It's important to figure out why the error code is happening before trying to fix it. This will save you time and ensure that the issue is resolved correctly.

Baxi Boiler Trouble with Gas Supply [E133 Error]

The E133 error is a common issue in Baxi boilers, especially if they haven't been used for a while, like after summer or vacations, and you're about to start using them in the colder months, like autumn and winter.

When you try to turn on the boiler after it's been idle, it may not ignite despite several attempts and eventually gets stuck, showing the error code 133 on the screen. Depending on your model, the display might show the complete number 133 or split it into two parts, displaying E1 and then 33 (E133).

According to the manual, the Baxi boiler lets you try restarting up to 5 times. If it still doesn't ignite within these attempts, the boiler locks up, showing the error 133.

For both old and new models, the E133 error suggests there might be an issue with the gas supply. Possible reasons for gas trouble include:

  • Air gets into the gas circuit, especially during startup at the end of the heating season.
  • A faulty gas regulator or one that doesn't match the type of gas used leads to insufficient gas for ignition.
  • The cable connecting the control panel to the ignition electrode has a lack of continuity or a short circuit.
  • The gas tank tap is closed, and you might not notice it.

If you encounter the E133 error in a Baxi condensing boiler, consider these two additional points:

  • The smoke recirculation mechanism might be clogged, causing a smoke anomaly.
  • The condensate discharge pipe could be blocked.

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How to Fix E133 Error Code

If you are experiencing an E133 error code on your Baxi boiler, here's how you can fix it:

“We advise you to call a professional heating engineer to diagnose and fix your boiler issues.”
Check The Gas Supply

First, make sure that all gas appliances in your home, including the boiler, are working correctly. If they are not, contact your gas supplier to check for any issues with the gas supply.

Check The Boiler Ignition

This might sound simple and not very likely, but it happens. If your boiler doesn't start, check if the gas inlet tap is open. Sometimes, it can get stuck, especially after not being used for a while. Also, consider that the gas inlet tap could be jammed or damaged, and if so, it needs to be replaced.

Reset The Boiler

A simple reset can sometimes fix the error code.

How to Reset Your Boiler

The process of resetting your boiler is the same, no matter what's shown on the display.

Here's what you do:

  1. Turn the selector switch to the R (Reset) position.
  2. Hold it down for at least 5 seconds, then let go.
  3. The fault code will change to show the current temperature of the boiler.
  4. If you have a neon indicator model, the flashing flame failure light will stop, and the burner light will come on.
  5. After a few seconds, the burner light (orange) will turn on, indicating that the burner is working and the temperature should start going up.
  6. If the boiler keeps turning off frequently, there's likely a problem. In that case, it's best to contact your installer or service engineer for help.
Check The Condensate Pipe

If you have a frozen or blocked condensate pipe, this could be causing the E133 error code. If it's freezing outside, your condensate pipe might freeze. To fix it, pour hot water on the frozen pipe to melt the ice and reset the boiler.

condensate pipe of a Baxi boiler

Boiler condensate pipe

Problems With Boiler Parts

If your Baxi boiler shows an E133 error, it's often due to issues like a gas supply problem or a frozen condensate pipe. However, the problem could also be linked to faulty parts in the boiler.

Here are some other possible reasons:

  • Faulty gas valve: Might need a replacement.
  • Worn-out spark electrode: This may require cleaning, bending, or replacement.
  • Faulty PCB (printed circuit board): The PCB acts as the brain of the boiler and might need to be replaced.
Bleed The Radiators

Air can sometimes get trapped in the gas line, causing the boiler to shut off. If you bleed your radiators, it helps get rid of air and makes sure the gas flows well.

How to Prevent E133 Error Code From Happening in the Future?

Prevention is always better than cure, and there are some simple steps you can take to avoid encountering the E133 error code in the future:

Schedule regular boiler maintenance.

Regular servicing of your boiler by a qualified engineer will not only keep it running smoothly but also help identify and address potential issues early, preventing costly breakdowns and ensuring the longevity of your heating system.

A serviced Baxi boiler

A serviced Baxi boiler

Annual boiler service.

Getting an annual boiler service is crucial to ensure that your boiler operates efficiently and safely. Plus, it will help to reduce your household energy bills.

Keep the condensate pipe clear.

To avoid a frozen or blocked condensate pipe, make sure it is installed correctly and regularly check for any debris or obstructions.

Check for gas leaks.

Gas leaks can cause low pressure in the system, leading to an E133 error code. If you suspect a leak, contact your gas supplier immediately.

Know when to call for professional support.

While some issues can be fixed by yourself, always seek professional help if you are unsure or uncomfortable handling the problem.

Get Professional Support from Serviceteam London

If you are facing an E133 error code on your Baxi boiler and need expert assistance, look no further than Serviceteam London.

Our team of fully qualified and safety-trained engineers is available 24/7, 365 days a year, to provide you with prompt and reliable boiler repair services. We have extensive experience in dealing with all boiler issues, including the E133 error code, and we guarantee to get your boiler up and running in no time. However, if you own a Baxi boiler, you can check out our blog about E1 fault code for more information on Baxi boilers.

Contact us today for boiler-related concerns, and let us keep your home warm and comfortable.

Stay warm and safe with Serviceteam London!
Happy heating!


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