What Does E1 Mean on a Boiler? Error Code Causes & How To Fix It

James Elston
Written by James Elston
Updated on 25th April 2024
Posted on 3rd March 2024
what does e1 mean on a boiler

What does E1 error code on a boiler mean? How can it be fixed?

baxi boiler e1 error code

The error code E1 on a boiler is usually an indication that your boiler is Low on pressure and is one of the more common error codes for Baxi, Potterton, and Main boilers.

The E1 Error code suddenly appears on your boiler. It is unlikely that your boiler has an E1 Error Code, however, we offer a variety of options to help you diagnose and fix the problem.

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Error code E1 showing on boiler – How to fix it

Boilers with low water pressure are prone to many problems and therefore it is possible to fix the problem yourself using our help, without calling a Gas Safe registered engineer.

There are many error codes available. E1 is the most popular. It is used by some boiler brands like Potterton and Main, Baxi boiler error codes and Ideal Boilers. These three boiler brand names are made by the same manufacturer, so they share the same fault codes.

If you want to give your boiler and MOT, see the latest boiler service cost guide for the average prices in the UK right now and see that here at Boiler Central we are among the cheapest.

Our Expert Gas Safe Engineer Says:

The E1 error code is a prevalent fault code on Baxi, Potterton and Main combi boilers due to it relating to low water pressure in your boiler. Simply topping up the pressure should make your boiler work again. If it doesn't, contact a Gas Safe engineer right away

James Murfin

Gas Safe Registered Heating Engineer

E1 boiler error codes & low water pressure

Low pressure in your combi boiler can be indicated by the E1 Error Code, so to get things back to normal, you can simply repressurise your Baxi boiler. As boilers age, it is common to repressurise a boiler and ensuring that you get a boiler service every year can stop issues like this from arising and you can book your boiler service here.

An Error Code can also be used to indicate that your boiler or gas supply is not working properly. The Error Code will help you pinpoint the problem. The E119 Error Code on a boiler might indicate low pressure.

Below is a list of all E1 Error codes as well as possible causes. A Gas Safe engineer should be called if the boiler pressure is not low enough to cause the problem. The law does not allow for the repair of gas boilers that are faulty yourself It is dangerous and must be done by a qualified heating engineer.

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How to top up pressure or repressurise your boiler

To effectively repressurise your boiler, begin by identifying the filling loop, typically located directly beneath your boiler.

This key component here is a silver flexible pipe with one or two black taps for the process.

Once located, use these two taps, turning them fully until they reach a 45-degree angle while keeping an eye on the boiler’s pressure gauge (little dial with a needle, like in your car)

The goal is to observe the gauge’s needle move to approximately 1.5 bar, indicating a successful pressure increase.

Once the gauge reflects that the pressure is back within the safe, green zone, you must then securely close the taps, ensuring they are returned to their initial start positions.

This step concludes the repressurisation of your boiler and should remove the E1 error code, stabilising your boiler’s pressure, and ensuring it operates efficiently.

E1 Error Code on Baxi, Potterton & Main boilers

Baxi customer service can be reached if you own a boiler such as the Baxi 600 combi boiler, even if it is still under warranty and this error code is common on Ideal boilers too.

It means that your pressure needs to be topped up and a good way to prevent this is you can get a Baxi boiler service every year to maintain your boiler and they cover Potterton boilers and Main boilers too.

E20, E28, E50,
Faulty components inside the boilerFaulty components can only be checked, fixed or changed by a Gas Safe registered engineer
E110overheating of the primary water or flue system has occurredIt is likely your boiler has shut down. You can try resetting your boiler and then monitoring if it starts back up. If the boiler does not reset, then you will need to leave it switched off and contact an engineer
E119Low water pressure in boiler – This means that the water pressure in the boiler has dropped below 0.5barYou. can top up the water pressure yourself by finding the filling loop and opening both taps at the same time.
E133This is a gas supply issue. Either there is no gas to the boiler or there is a blockage. This may even be caused by the gas been switched off by the provider.You need to ensure that there is definitely a supply of gas to your boiler. If so you can try and reset your boiler. If the error continues to show you need to call a Gas Safe engineer.
E133Frozen condesnate pipe. This can easily be fixed by the thawing of the pipe using warm water.With warm water, you will need to find your condensate pipe outside and melt the ice. Once done your boiler should work again.
E168This is an issue with your boiler but it is unsure what it is. Therefore for safety reasons, your boiler has shut itself off and you need to contact a Gas Safe registered heating engineer.Call a Gas Safe registered engineer right away.

Does the E1 fault code indicate that I need a new boiler or not?

You don’t necessarily need a new boiler immediately if you have E1, however, it does mean you need to start looking for signs your boiler may be costing you more money.

It is worth looking into replacing your boiler if you are paying high boiler repair costs, and you can read our guide and see why the cost of a new boiler may not be that much different when you add it up.

New boilers will also save you money on your gas bills so to get a boiler quote online at a fixed price, click get a quote now.

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What is the most common boiler fault?

The most common boiler fault is the E1 error code, which typically indicates low water pressure. This error is prevalent across various boiler brands and can often be resolved by resetting the boiler. However, regular inspections and annual servicing are advisable for sustained efficiency and safety.

What causes an E1 error code on boilers?

An E1 error code on boilers usually suggests issues with the appliance’s internal components or system. This can include a malfunctioning pressure sensor, faulty temperature probe, or problems with the heat exchanger. Incorrect installation or improper maintenance may also lead to this error.

How do I reset my E1 boiler code?

To reset the E1 error code, first, check and repressurise the boiler if necessary. Then, utilise the provided reset button on the boiler. If the error persists, it is recommended to consult a professional heating engineer.

How do you fix E1 on a boiler?

To fix the E1 error on a boiler, start by identifying the cause, typically related to low pressure. Check and adjust the pressure as needed, inspect for leaks, and attempt to reset the boiler. If these steps do not resolve the error, it’s advisable to contact a heating engineer for further assistance.

What do I do when encountering an E1 19 error on a boiler?

When encountering an E1 19 error on a boiler, the first step is to turn off the boiler and refer to the manual for guidance. This error may indicate issues with the expansion vessel, condensate pipe, or water pressure. Such problems often require professional attention. If unsure, always seek assistance from a qualified heating engineer.

Written by
James Elston
James Elston Director Of Boiler Central
Posted on: 3rd March 2024

James Elston is our resident boiler replacement and heating expert here at Boiler Central. With over 20 years experience in the boiler installation industry, James ensures that he knows everything there is about our Gas Safe boiler installations, energy saving and home heating solutions. This can be from simply procuring the latest best combi boilers, to reviewing and ensuring that Boiler Central maintains the highest standards across our boiler installation company.

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