Baxi E119 boiler fault code

How to Fix a Baxi E119 Boiler Fault Code Repair

Last updated on June 10th, 2024

The Baxi, Potterton and Main E119 boiler fault code indicates low boiler pressure, so you must repressurise your boiler to fix it.

Low boiler pressure will cause your boiler to not fire up when it drops below a certain pressure. You first need to check the pressure gauge and if it’s low, repressurise it until it’s at 1 to 1.5 bar.

I have been fixing boilers for over a decade and this is how I fix an E119 boiler error most of the time.

E119 Boiler Fault

It could be other problems causing the Baxi E119 low water pressure fault, but a leak is by far the most common reason for your boiler pressure dropping.

Baxi E119 error

The E119 boiler fault code should disappear when the boiler is repressurised, and you should hear the pump start to circulate the water in the boiler.

How to Reset a Baxi Boiler

The first thing I would check on a boiler that is not working, no matter what fault code is showing, is to check the pressure and reset the boiler.

Knowing how to reset it is the simplest way to get your boiler working again, as it might have just locked out.

To reset a modern Baxi boiler, you must find the reset button. This is a button that has ‘Reset’ on it. You have to press the button to reset the boiler.

Sometimes you have to hold it down for a few seconds, but on some, it just needs to be pressed.

How to reset Baxi boiler

If it’s an older boiler with a knob to turn the boiler on and off, then you will need to turn it fully anti-clockwise and hold it there until it resets.

E119 Error Keeps Happening

If your boiler pressure loss keeps happening, showing E119 and going to lockout, then you most likely have one of these problems:

  1. A leak on the boiler or central heating system
  2. If the boiler pressure is dropping straight away after repressurising, you must have a serious leak or an open-ended pipe on the central heating system
  3. Expansion vessel pressure problem


A leak could be anywhere on the boiler or heating system and is most commonly caused by a leaking radiator valve

Open-ended Pipe

An open-ended pipe is usually obvious as the boiler won’t hold pressure when repressurising the boiler.

This could be on a pipe under the floor, the pressure relief valve stuck open, or maybe the radiator bleed valve is open or missing

Expansion Vessel Pressure

An expansion vessel pressure problem is quite common which means the expansion vessel will need to be recharged or replaced to fix it.

How to Repressurise a Baxi Boiler

To repressurise a Baxi boiler, you must find the boiler filling loop. If it’s a built-in filling loop, it will be two blue handles under the boiler.

Both handles must be turned to open and then closed when the pressure reaches 1 to 1.5 bar.

Baxi combi boiler filling loop
Baxi combi boiler filling loop

If it’s an external filling loop, it will probably be on two of the pipes under the boiler. It will most likely have two valves with black handles and a flexible hose connecting them.

You must open both valves to repressurise the boiler, then close them both when it is repressurised.

You should be able to hear the water filling the central heating system when both valves are open, if not, then the boiler filling loop might have problems or the house’s mains water might be turned off.

Other Causes of an E119 Fault

Other causes for the E119 boiler fault code, if it’s not low water pressure, could be:

  • Pressure sensor
  • PCB

Baxi Boiler Guides


The Baxi boiler E119 diagnosis code is very easy to fix most of the time as it’s simply a case of repressurising your Baxi, Potterton, or Main boiler.

If your boiler keeps losing pressure then you will need to find and fix the cause of this or you will keep getting an E119 boiler error.

A Baxi boiler E1 code is the first half of the full code as it’s typically shown in two halves flashing E1 then 19, or whatever the rest of the code is.

Feel free to ask me any questions in the comment section below and I’ll try my best to help.

Please share this post if you find it helpful.


Why does my Baxi boiler keep losing pressure?

Your Baxi boiler keeps losing pressure because you most likely have a leak on your central heating system, which could be at the boiler.

Another reason your boiler keeps losing pressure could be an expansion vessel problem, or the pressure relief valves might be letting by.

How do you clear the fault code on a Baxi boiler?

To clear the fault code on a Baxi boiler, like Baxi E133 and E119, you must reset the boiler. If the fault code appears after resetting the boiler, you will need to find and repair the problem causing your Baxi boiler to lock out and show a fault code.


  • Steven Reid

    I am a full-time plumber and Gas Safe registered engineer. I incorporated Housewarm Ltd. in 2011 to provide heating and plumbing services to homes in Newcastle upon Tyne, England. I now blog about what I've learned over the years to help DIYers and plumbers.

    View all posts
Share this post

2 thoughts on “How to Fix a Baxi E119 Boiler Fault Code Repair”

  1. HI,
    I have a Baxi Due Tec that drops pressure over night. i have changed the prv and recharge the vessel and cant see any leak.
    My question is When the pressure drops from 2 bar (when the heating is on) to 1 bar when cold., but error E119 seems appear when the pressure is a normal running pressure and the needle is in low green zone on the dial. when i re pressure the you can hear the pressure switch click in just over the top part of green zone . Could this be a faulty water pressure switch.

    1. Steven Reid

      Hi Mike,
      Sounds like a pressure sensor problem, typically a sign of a dirty system where hard sludge builds up in the sensor. Could also be the pressure gauge but more likely the sensor.

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top