BAXI Boiler Problems & Troubleshooting

Common Error Codes, Fault Lights and How to Fix Them

Are you seeing any Baxi boiler error codes or fault lights? Let’s start with the common codes that our expert heating engineers see frequently!

Boilers can go wrong at any time and can cause stress and concern at the most inconvenient times.

Sometimes, before you call an expert, you can use reliable troubleshooting techniques to discover the cause which will help put to bed some of the worries you may have about repair costs and timescales as well as save money.

Having a renowned boiler, such as a Baxi boiler, can come in handy when you’re facing issues.

You will find there are many common error codes and fault light explanations online – which is why we always try to cover the most popular brands on our own website and form our own common questions with answers for you to try yourself at home before giving us a call.

So, firstly, are you seeing any Baxi boiler error codes or fault lights? Let’s start with the common codes that our expert heating engineers see frequently.

BAXI Boiler Problems: Common Error Codes & Troubleshooting
BAXI Boiler Problems: Common Error Codes & Troubleshooting

Common Baxi Boiler Error Codes

Baxi Boiler 110 Error Code

In houses with older, traditional radiator heating systems, you are more likely to see Error Code 110. This simply means your boiler has overheated.

Suggested fix

Firstly, attempt to bleed your radiators. This simply means you’re letting any trapped air in the radiator out.

Not only does air in your heating system result in your entire system being inefficient, but it can stop the boiler from doing its job and overheating.

In more modern houses with underfloor heating, this is less likely to be an issue, but it can still happen.

Baxi Boiler E133/E28 Error Code

During the winter months, it wouldn’t surprise us if you see error codes E133 or E28. Condensate pipes in Baxi boilers (and most other brands) transport the wastewater away from the boiler, straight into the drain outside.

This is a vital part of your boiler’s day-to-day running as it prevents the water from causing any damage to the mechanics of the boiler, however, when it gets cold outside, the drain can freeze and so can the condensate pipes!

Suggested fix

Safely pour warm water over the frozen pipes outside your house or if you’re not sure you know where the pipes are or fancy a professional’s second opinion give one of our Gas Safe registered engineers a call.

Baxi Boiler E199 Error Code – Low Boiler Pressure

This error code means your water pressure is low. The normal water pressure for a Baxi is between 1.0 and 2.0 bar.

Suggested fix

You may need to check your gauge and note if the water pressure is less than 1.0 bar. It is not uncommon for boilers to need to be repressurised and in most cases, you can do this yourself.

Some people use rigid filling loops, flexible filling loops or an Easy-Fill permanent filling link.

Recommended reading: Boiler Filling Loop: Installation, Repair & Replacement

If this isn’t something you have or know how to use, we recommend you call an engineer to top up your Baxi boiler’s pressure.

Baxi Boiler E168 Error Code

When your Baxi boiler has an issue but cannot work out where the problem is, it will show this error. The most common cause for seeing this code is when there is a problem with the electrical supply (PCB lockout error).

Suggested fix

If your power is running fine to the rest of your house, you will need a registered Baxi engineer to diagnose the fault.

Are you not seeing an error code, but a flashing light instead?

Then, check these out…

Common Baxi Boiler Fault Lights

Green Flashes

In many cases, green flashes do not require a fault-finding process and you can usually allow your boiler to continue as normal.

1 green flash simply means your boiler is up to the temperature you requested.

3 green flashes means the flame went out. If this is a temporary issue, the boiler should reset by itself. If it cannot fix this it will turn into 3 red flashes (see red flashes and also see how to manually reset your boiler below).

4 green flashes means there has been another temporary error that should be sorted with a self-reset. 4 green flashes are indicative of a communication error between PCB and Control.

5 green flashes, as above, can be fixed by the boiler self-resetting. This fault means there has been a parameter error on PSU/PCB.

6 green flashes is also a temporary error that is fixed by a self-reset however, the cause for the fault is unknown.

Red Flashes

1 red flash means there could be temperature, sensor or flow faults. You will need an engineer to locate the issue.

2 red flashes is a sign your boiler has overheated. Try bleeding your radiators before calling an engineer.

3 red flashes, as discussed above, means your ignition is failing to light and that your boiler has self-reset 5 times and is still facing the same issue. Unfortunately, some Baxi boiler models can be prone to this fault and you may need to replace chamber seals if they have worn or degraded over time.

4 red flashes are indicative of issues with your fan. If the fan isn’t working correctly, it may not be pushing flue gases out away from the flue. It is integral you call an expertly trained engineer to ensure your fan is replaced.

5 red flashes is a parameter or PSU error that cannot be fixed by a self-reset. Call an engineer to help you locate the issue.

6 red flashes is an unknown error. You will need an engineer to help fix this.

Did you find these common error codes and fault lights helpful?

If not, try these common troubleshooting Q&A’s that we’ve got below.

Other Common Baxi Boiler Questions

How do I reset my Baxi boiler?

If in doubt, always try this first so that you don’t call an engineer out for no reason. It’s easy to do.

Simply hold the reset button for a minimum of 5 seconds and then release it. If the process is successful your boiler will reboot and begin operating as normal.

If you find yourself doing a manual reset regularly, you may need to call an engineer and explain the situation.

Baxi boiler no hot water/heat

Unfortunately, there are a variety of problems that could cause this fault in your boiler, so you’ll need to get an engineer out to locate the issue.

Recommended reading: No Hot Water from Boiler: Our Ultimate Troubleshooting Guide

An engineer will be looking for broken parts such as diaphragms or airlocks.

They will also check valves and any motorised valves which may have failed as well as your thermostat and water pressure.

My radiators aren’t getting hot

When there is a build-up of debris inside the heating system (in such cases a central heating power flush is highly recommended) or if a lot of air is trapped, you’ll get a very inefficient system and/or an unequal heat distribution throughout the various radiators.

If you don’t know how to bleed a radiator yourself you can get an engineer out, otherwise, this is something you should be able to fix on your own.

Should my Baxi boiler be making loud noises?

You should always be listening out for your boiler and if it starts making unusual noises such as gurgling, banging or a high-pitched whistling, there are possible issues with the water pressure or air in the system.

You can try repressurising if you’re comfortable with the instructions noted above, or you can call an engineer straight away.

What is kettling?

Kettling is another noise you could hear with your boiler and it’s very similar to the noise a traditional kettle makes as it heats up – hence the name.

This is caused by a build-up of debris or limescale inside the boiler and sometimes it can be fixed but often the parts need replacing.

I think my Baxi boiler is leaking

If you ever notice your boiler dripping you need to call an engineer. The most likely culprit will be a broken or heavily deteriorated part.

The engineer will start by checking the area the leak is coming from and they’ll let you know if a component is going to need replacing.

Why is my Baxi boiler switching itself off?

Once again, this is the sort of fault that can be hard to pinpoint on your own.

A qualified engineer will be able to run a variety of tests that can look at your water pressure, valves, thermostat and water flow to check what is causing this boiler fault.

My Baxi boiler pilot light has gone out

You’ll need an engineer here as it’s most likely your thermocouple has broken and the component will need replacing in order to get gas into your boiler.

You may need to replace parts so we recommend having an engineer out for this one.

Recommended reading: Boiler Pilot Light Out: How to Relight Pilot Light on Boiler

I’m continuously losing pressure in my Baxi boiler

Did you recently bleed your radiators? If so, it can commonly cause boilers to lose pressure momentarily.

Keep an eye on it and it should come back. If not, you’ll need to do some checks and ensure there are no water leaks in the system.

If there are, you’ll need an engineer. If there aren’t, you may just need to replace the pressure relief valve.

I’m having thermostat issues with my Baxi boiler

If there aren’t any clear issues with your thermostat and it’s definitely switched on properly (i.e. this isn’t just a user error), then you may need to replace the thermostat, which may require help from a professional.

My Baxi boiler keeps locking out

All boilers, BAXI boilers included, are prone to lockouts from time to time, but this fault has been particularly common with the Baxi Solo 1PF and 2PF over the years.

The root of the problem comes from the boiler overheating. The boiler locks out to preserve any internal components and further damage.

This is not easy to diagnose without fault codes. Asides from leaks, there are other problems that can cause a boiler to lock out including fault codes: 110 (overheating), to 160 (a faulty fan) or even 166 (air pressure switch fault).

A common culprit for this fault on Baxi boilers is a lack of pressure. If your system is set lower than 1.5 bar then it won’t operate correctly.

Now, the quick fix is to top up the pressure using the filling loop.

Once you’ve topped up the pressure, you’ll need to reset the boiler. On the Baxi 1PF you’ll see an orange button. On the 2PF there will be a red button. These buttons will reset the boiler and get it up and running again.

But here lies a problem. The boiler has lost pressure. And that means there is a problem that needs to be fixed.

Most Baxi boiler faults where the system has lost pressure are because of leaks in the system.

You can do some visual checks to try and isolate the problem. Check for leaks on:

  • Radiators
  • Towel rails
  • Pipework
  • Radiator valves
  • Beneath the boiler (this could be the pump)
  • The expansion vessel

Your Baxi boiler problem is not listed here?

Don’t hesitate to get in touch as someone from PHS can be out within 24 hours to help put your mind at ease and warm your house up.

If you’ve located the fault and would like a specific price for your boiler problem, speak to a member of our team today to receive a quote.