Boiler repair costs can be expensive. But new boilers can be too. So we’ve compiled a list of common problems you may run into, how much they cost to fix on average (including labour), as well as the problems you may be able to handle yourself.
If you know there’s a problem with your boiler but don’t quite know what the fault is, first consult the manual. It will have a guide to the fault code being displayed and give you an idea of what to do, whether it’s something you can remedy yourself or need to call a professional to do. If you can’t find your physical manual, most of them are searchable online.
Two safe DIY fixes
Never, ever attempt to fix your boiler if it involves opening the boiler casing. Only qualified, Gas Safe registered engineers should go inside the boiler. Having said that, there are a couple of common faults that don’t involve opening it up, so have a go at sorting them out yourself:
1. Frozen condensate pipe
During a cold winter, it’s pretty common for the condensate pipe of your condensing boiler to temporarily freeze and render your boiler useless (because it will shut itself down for safety reasons).
However, don’t worry because there are steps you can take to thaw out the pipe yourself without calling in a professional. Please note: once this is done, make sure you insulate your condensate pipe properly with foam – a quick fix to stop this from happening again.
2. Low boiler pressure
There are a few reasons your boiler might lose pressure; your central heating might have been off for a very long time, it could be a leak, or sometimes it happens when you’ve been bleeding your radiators.
How to repressurise your system
You can repressurise your boiler yourself by opening its filling loop taps until you get the pressure between 1 and 2 bar. Then close both taps and your boiler should fire up again.
If your boiler loses pressure often, get it checked by a Gas Safe registered engineer to see if they can fix the issue for good. If some radiators heat up and cool down more readily than others, they may need bleeding or balancing. Check out our how to balance your radiators guide for more info.
Average cost to repair a boiler
So you’ve checked the manual, and it’s not a fault you can fix yourself. Commiserations. Keep reading for the average costs of some of the most common faults.
Average repair range is between £100 and £500
There are a great range of different repairs that a boiler might require, so it’s difficult to put a number on repairs, but the average cost of repairing a boiler will range from around £100 to £500 depending on the kind of problem.
Below we’ve compiled a list of common faults and some average repair costs, including labour, that you can use to brace yourself for the coming expense. Do remember that these are ballpark estimates, and prices will range up and down depending on where you live.
| Boiler part name | Approx. avg cost to replace part (including labour) | What this boiler part does |
| Diverter/zone valves | £220 | Directs the flow of heated water from the boiler to the radiators or taps/shower |
| Printed circuit board | £300 | The boiler’s control room |
| Water pump | £250 | Pumps heated water around your central heating system |
| Fan for combustion | £275 | Moves air through the boiler for combustion |
| Gas valve | £250 | Regulates the gas flow to the burner |
| Overheat thermostat | £115 | Stops your boiler from overheating |
| Automatic air vent | £115 | Lets air out of the boiler |
| Pressure relief valve | £125 | A crucial safety component that relieves a build up of pressure |
| Thermocouple (only found in older boilers) | £20 | An essential component in preventing gas leaks if your pilot light goes out |
| Ignition systems | £125 dependant on parts | Ignites the pilot/main flame |
How to prevent boiler breakdowns
To avoid any future boiler breakdowns, an annual boiler service is the single most important thing you can do.
To protect yourself and your home against current or future issues, HomeServe offers boiler cover and heating breakdown insurance you can rely on.
Why service a boiler?
Getting your boiler serviced annually is absolutely the best way to avoid breakdowns and unexpected costs. Your engineer can diagnose minor problems earlier before they turn into major faults. It’s also worth noting that if you don’t get your boiler serviced annually, you’ll most probably invalidate its warranty.
How much does a boiler service cost?
How much does a gas boiler service cost? The average price of an annual service is £80-90. How much does a combi boiler service cost? Around the same.
Our team of Gas Safe registered engineers is ready to help
If any component of your hot water and central heating system needs looking at, we offer a one-off repairs service to identify and fix any problems.
If your boiler can’t be repaired, we’re working together with BOXT, one of the largest boiler installations companies in the UK, who offer a speedy boiler installation service so you can get your home back up and running again.
Boiler repair FAQs
How much should a boiler repair cost?
The average cost of a boiler repair is between £100 and £500, depending on the specific issue and on other factors including where you live.
Is it worth repairing a boiler?
If the boiler is less than 10 years old, with a fairly uneventful history, a repair is probably well worth it. If your boiler is older than 10 years and is a non-condensing boiler, you should consider swapping it for a newer, more energy-efficient model.
How long should a boiler repair take?
This really depends on the type of problem – it could take an hour to replace a part, up to a couple of days if the problem is severe.
