What's in this article?
If your boiler is broken.
So is your will.
So are your dreams.
So is your home.
As such. You’ll want the cheapest fix, or the cheapest new boiler. Or do you?
So, here are (some surprisingly) common issues – which are free and easy to fix. Closely followed up by more sinister and costly reasons why your boiler isn’t working. (Looking for a new boiler? Check out our summary of the best boiler brands).
If your boiler's super-old and looks way beyond repair, find out what replacement you need along with costs.
Common broken boiler issues (with free and easy fixes)
#1 - Check the boiler is switched on
An absurd and seemingly patronising statement at first, but, boiler installation companies up and down the UK are relentlessly earning call out fees for customers who haven’t realised their boiler has been switched off – sometimes at the mains.
It can be human error, or perhaps you switch off appliances whilst sleepwalking but one of the most common causes are power cuts.
Your boiler probably hasn't broken, so switch the bugger on.
#2 - Have you paid your gas bill, or does the gas meter have credit?
Another silly reason at first glance but understandably common. People take boilers for granted and aren’t always acutely aware of the corresponding gas bill.
If you don't pay your energy bills, your boiler won't work. Simple.
Perhaps you upgraded to Netflix HD last month sending you tumbling beyond your overdraft. Or, it’s just the energy companies fault. The scumbags.
Either way – do check.
The good news is that combi boiler is much cheaper than the likes of immersion heaters, so it's not all bad.
#3 - Boiler not working? Check for low pressure
Boilers will naturally lose pressure over time for a number of reasons, most of which are nothing to be concerned about. If your boiler's not working, and it's simply low on pressure, you'll be back up and running in no time.
Read how to breath new life into a broken boiler that's losing pressure.
It’s super easy – one check and one tap turn.
How to check if your boiler's not working because of pressure issues
Glance at your boilers pressure gauge – the clock-like feature staring at you like a cyclops from the front of your boiler. When the boilers off, its arrow should point to the green zone – around 1 BAR.
Your boiler pressure being too high is also a thing.
How to fix your boiler's pressure issues
We recently published an article about boilers losing pressure - it'll tell you how to fix it.
#4 - Boilers pilot light may have gone out / not catching
To ignite the gas and deliver heat and hot water, the boilers pilot light (basically a tiny internal flame) will need to be alight when your boiler is active, in order to burn the gas.
Sometimes this flame will go out, whether caused by sudden drafts or wandering spirits trying to make contact.
In older boilers, you’ll be able to check this by peering through the casing to visually check on the boiler flame. If it’s out, you should try restarting/resetting your boiler. If the boiler is still not working, you'll need to call (and pay) a heating engineer (sorry).
#5 - Check your condensate pipe (winter conditions only)
Your condensate pipe travels from your boiler, to (usually) the nearest outside wall and is where excess liquid caused by condensation from your boiler is deposited outside.
This small amount of slowly dripping water is naturally vulnerable to freezing in cold weather.
A frozen condensate pipe will lead to a blockage, meaning the excess water has no escape route and your boiler will shut down upon detecting this. It's a surprisingly common cause of a boiler that's not working.
How to fix a frozen boiler that's not working
Gently pour warm water over the frozen condensate pipe until the frozen water has melted away.
After you’ve tackled that – reboot your boiler.
How to (try to) prevent
Checking regularly on the pipe as though it’s an orphaned chick you rescued from a fallen nest is one avenue.
But, wrapping the external part of the pipe in foam or cloth to prevent future freezing is recommended.
#6 - Check your boiler's thermostat
Like Governments blaming immigrants and the poor for their shortcomings, boilers are often held accountable for the failings of their controllers.
If you’re privileged enough not to have to physically approach your boiler to switch it on, you should check if it’s actually your timer that’s not working. Your boiler might be working just great.
How to check if your boiler's not working because of a faulty thermostat:
- Check it’s switched on with a full charge or working batteries
- Ensure that the temperate is turned up to the level you require
- Check your Wi-Fi connection if applicable with the boiler thermostat
- Run over the time settings, making sure no ‘vacation modes’, stand-by options or unnoticed daily schedules have been set.
How to fix
- Replace the batteries in your thermostat
- Clear any settings and restore to manual operation
- If all else fails, refer to the thermostat manual
Want to save money and energy on your heating bills? If so, you should consider installing one of the best smart thermostats.
Common issues for a boiler that's not working (requiring an engineer and £££)
#1 - Pressure issues (due to faulty parts)
Boilers thrive on pressure and require a balance of it so delicate, that butterflies start to look like drunken Geordies.
A loss of pressure will result in an inadequate amount of water running through your boiler that will, in turn, struggle to provide heat to your home – or enough hot water, obviously.
Too much pressure and your boiler won’t have time to thoroughly heat the water – amongst other issues, like putting internal parts under pressure and causing leaks.
Culpable boiler parts include; expansion vessel, pressure release valve and the heat exchanger. These are all too often heartbreakingly expensive repairs that are much more likely to lead you down the new boiler route.
How to check if your boilers not working because of a leak
Refer back to the trusty pressure gauge on your boiler; it shouldn’t be under or above the green zone whilst the boiler is switched off and never in the dreaded red zone.
If it is, switch the boiler off.
How to fix a leaking boiler that's not working
A qualified Gas Safe heating engineer will need to strip the boiler down and inspect all possible parts – replacing them where possible.
Boiler over 10-years old with a faulty part? Gently massage the idea of a new boiler into your thoughts. You’ll thank yourself later.
Boiler not working and the repair going to cost you an arm and a leg? Save your last two limbs and upgrade to a hot new boiler with a 10-year warranty and mind bogglingly low monthly payments.
#2 - Leak in the boiler, or heating system
Leaks within the boilers internal parts or around the heating system (pipework) aren’t just bad for your carpets and floorboards.
They’ll cause a loss in pressure that we’ve already established is a boiler killer.
How to check
Look for patches of water and drips directly underneath your boiler (within the case if you can) and also check the pipework throughout your house, particularly around the joints/bends in the pipes.
How to fix
You’ll need a boiler engineer to give your system a once over and either replace any faulty parts or secure any leaks in pipework that can be repaired.
If it’s an internal boiler part that’s failed, you may well be better off upgrading to a new boiler rather than falling into the trap of eternal repairs.
Boiler not working during the financial low of your life? Typical. Get a new boiler now – and pay monthly, with no interest!.
#3 - Boiler simply won’t turn on (no power at all)
If your boilers not working to the point where it appears utterly dead with no sign of life. It’s likely an electrical issue.
Most commonly this will be a busted PCB (circuit board) and could set you back a few hundred pounds.
How to check
The age-old off and on again at the mains power is your only real play here. You’re going to need an engineer to diagnose the issue.
If your boilers not working at the same time as your TV, kettle, lights and washing machine – get calling your electrical provider.
How to fix
If your PCB board has gone into the long night then it’s going to need a costly replacement.
Hopefully, though, you’ll get away with a faulty fuse or another less expensive repair.
Is your boiler working but not providing hot water?
A boiler not working that still provides heating is a brave boiler indeed.
But it definitely has a faulty part, and it’s probably the diverter valve.
The aptly named diverter valve diverts the water to either your radiators, hot water outlets or both – depending on what you’re demanding from it.
Here's some help if you've got no hot water from your boiler.
How to fix
Your diverter valve is going to need replacing, or you’re going to need a new boiler.
Is your boiler working but your radiators aren’t getting hot?
This is unlikely to be your boiler not working.
Over time, heating systems – pipes and radiators – become congested with metallic debris and congealed dirty water.
This causes blockages within the system, like fat in the arteries of the morbidly obese.
You'll know you've got a sludge issue if your radiators are cold at the bottom. That's the most common.
On a side note, and much rarer instance, your boiler may not actually be powerful enough for your home's needs. Read more about which size boiler your homes needs.
A heating engineer is going to need to flush your system – probably a power-flush to cleanse the pipework and radiators of debris and bad vibes. It’s the spa break your boiler deserves.
As a preventative measure, you should also invest in the installation of a magnetic boiler filter. A powerful magnet that attracts more filth than a pub with a flat roof.
Treating yourself to a new boiler? Heatable fit an Adey Pro magnetic boiler filter, as standard with every new boiler installation. We even throw in a chemical treatment for your radiators.
Common issues, for common boilers that don't work
Worcester Bosch boiler not working
Common reasons your Worcester boilers not working & Worcester Bosch boiler error codes:
|Worcester Bosch Fault||Likely Error Code|
|Pressure too low/high||A1, CE 207, H07, 224V, 1017W, 2970B|
|Pilot light issue (not lighting)||EA, F7, FA, EA227, F7 228, FA306|
|Heat Exchanger error||2963 B, 2964 B, 2966 B, 2967 B|
|Fan Fault||C6, T2, C6 215, C7 214, C1 264|
Vaillant boiler not working
Common reasons your Vaillant boilers not working & Vaillant boiler error codes:
|Vaillant Fault||Likely Error Code|
|Pressure too low/high||F.24, F.12, F.22, F.73|
BAXI boiler not working
Common reasons your Baxi boilers not working & Baxi boiler error codes:
|BAXI Fault||Likely Error Code|
|PCB (circuit board) error||E100, E167, E168, H.02 - 02, 4-5 Green Flashes|
|Pressure too high/low||E28, E119, 117, 118, 119|
|Pilot light error||E128, E129, E384|
Ideal boiler not working
Common reasons your Ideal boilers not working & Ideal boiler error codes:
|Ideal Fault||Likely Error Code|
|Low water pressure||F1|
|PCB (circuit board) error||F9, L9, F8, L8|
Boiler still not working? Here's how you can get the best deal
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