Common Boiler Faults

September 6, 2019

For most people, boiler issues are expensive. The minute there’s an issue, most of us instinctively reach for our wallets. However, some common boiler faults can be easily fixed without the need of an expert. In this blog, we explain some of the most common faults and detail how you can go about fixing them for yourself. To prevent boiler issues in the first place check out our article on boiler maintenance

My radiators won’t heat up!

Encountering a cold patch on a radiator is probably the most common boiler problem to affect homeowners. The issue can severely hamper the distribution of heat in a home and is typically caused by excess air or sludge that has become trapped inside the system. If the cold patch is at the top of the radiator, it’s probably trapped air. If the cold spot is at the bottom of the radiator then it’s most likely a build-up of sludge. Both issues require different fixes but can sometimes be handled by homeowners without the help of a professional.

If the cold patch on your radiator is at the top, then it’s best to try and ‘bleed’ it. Bleeding a radiator is a straightforward task and won’t take long. To start with, turn your central heating on to full, let it heat up and then switch the system off. Using a radiator key, open your radiator’s valve and make the air escape. Wait until the air stops and catch any excess water that has escaped. Finally, check your radiators are fully working again by switching the central heating back on.

Even if the cold patch is at the bottom of the radiator, it’s still worth trying to ‘bleed’ the system. However, if you don’t notice any trapped air escaping the system, then it’s probably time to bring in an expert. Often, build-ups of sludge will need to be cleaned out with a power flush. A boiler engineer will be required to handle the task, which will cost around £350 – £800 depending on the number of radiators affected by the problem.

My boiler is losing pressure!

Nowadays, most boilers are fitted with a pressure gauge. The gauge helps you to check whether your system is running at the right pressure. Pressure in your boiler must be kept around one bar. If you notice that the pressure is too high, then you will need to bleed the system. To do this, follow the steps set out earlier in this article.

Dealing with low pressure is a different issue, but still manageable for most homeowners. Check your boiler manual to see if it’s possible to re-pressurise the system for yourself. It’s important only to follow the instructions set out in the manual and to bring in an engineer if you have any doubts about what you’re doing. If your boiler allows for re-pressurisation, then you’ll be able to add more water to the system. This will bring the pressure gauge back up to a more normal level.

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My boiler is making odd noises!

It’s never good to hear noises coming from your boiler cupboard, but many homeowners choose to ignore the problem. However, unwanted noise from a boiler can be the sign of a problem and might need the attention of an expert. If your boiler is making a whistling noise, then it’s most likely trapped air in the system. Again, it’s worth bleeding your radiators to see if it has any effect.

Similarly, boilers sometimes make a ‘gurgling’ noise that can be related to a frozen pipe somewhere in the system. As with all frozen pipes, it’s crucial to locate the problem and try and fix it before it causes a further issue. If the noise doesn’t fit either of these descriptions, but it’s louder than a murmur, then it’s worth giving someone a call. Not doing so might mean you end up having to pay for a significant boiler repair, or even worse, a replacement.

My boiler is leaking!

There are several reasons why boilers leak and they range in severity. Leakage can often be the result of a faulty installation. That’s why it’s so important to use a reputable tradesperson to get the job done in the first place. Using a trusted tradesperson website like Checkatrade helps to ensure you only find someone up to the task. If you think your boiler has been installed incorrectly, then you must call the installer immediately. Any tradesman worth their salt will come back to give it a look, but if they refuse, you might have to bring in someone else.

My boiler keeps turning on and off!

There are some things that can cause a boiler to cut out intermittently. Unfortunately, many of them are severe problems and will require urgent attention. Before bringing in an expert, ensure that the issue is not pressure-related. Sometimes low pressure can cause boilers to cut out, if this is the case, it can be fixed quickly as explained earlier in this article. If the pressure levels seem okay, then it could be system blockage or a faulty pump. In this case, the best course of action is to bring in an expert who can fix the fault.

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