According to the government of UK, 90% of homes use central heating combined with a boiler system.
Boiler breaking down unexpectedly can cause discomfort in the cold seasons and disrupt your heating and hot water. In many homes in the UK, a heating system can fail without a warning sign.
It is important to be able to diagnose boiler problems. Let’s explore the most common boiler faults, why they happen and whether you need to call a certified engineer.
There are many issues that can lead to a boiler breakdown. From low Pressure to frozen pipes or dysfunctional thermostats.
Having prior knowledge about these problems can help you stay protected with a boiler cover and minimise long-term repair costs. Let’s cover these boiler breakdown problems in detail.
Common Boiler Breakdown Problems and Solutions
Low Boiler Pressure
Boiler stopped working? A common issue is the drop in the boiler pressure, due to which your radiators fail to heat properly.
To find out the Pressure, check the boiler pressure gauge. Here, the Pressure should be between 1 and 1.5 bars.
Anything below this threshold means your boiler needs repressurising. Prevent breakdowns with regular boiler servicing and keep the pressure at optimal level.
Frozen Condensate Pipe
If the boiler is not turning on in cold weather, maybe due to a frozen pipe. You can fix this by warming the pipe gently with warm water. If this situation persists, consider insulation.
This issue happening in the condensing boiler is because of a condensate pipe which transports the water away from the boiler. The pipe which is connected to the drain outside. Because of its location it can be prone to solidifying.
More often, boilers will show a fault code or warning notification if the condensate pipe has been frozen. This code can vary for different boiler manufacturers.
Faulty Ignition or Pilot Light
A small gas burner which is permanently lit in your boiler is the pilot light. This light becoming faulty and going off every now and then is a fault. Your thermocouple is likely broken and stopping the gas supply.
The thermocouple is a safety device in the boiler that checks for temperature changes in your pilot light. So, if it’s broken then it cannot detect any temperature change and hence the issue.
So, if this situation arises, it’s better to consult with a professional rather than attempting to open sealed parts yourself.
Leaking Boiler
Leaks may lead to pressure drops or serious boiler faults. Loose joints, corrosion and broken seals often cause leaks.
Don’t try to fix a leaking boiler yourself. It’s better suggested to consult with an engineer immediately, as water and electricity can be a dangerous mix.
Thermostat Problems
A malfunctioning thermostat can make you wonder: why is my boiler not working?
Inaccurate settings or faulty batteries are common causes for thermostat malfunctioning. Try getting new batteries or adjusting the temperature settings.
Additionally, as the seasons change, it’s important to note that your home might get warmer than usual and the temperature set in the thermostat might be lower than your home temperature. In this scenario, a simple increase in the temperature of the thermostat can solve the issue.
Clogged Heat Exchanger
Another common boiler problem is a blocked heat exchanger. You can spot this issue from kettling noises or stop-and-go heating. This happens when there’s a limescale build-up. For this, you can use a clean-up or chemical flush.
Faulty Circulation Pump
When the pump fails, water is unable to circulate. This can leave your boiler from working completely. You can spot this issue if your radiators are cold or if the boiler is firing.
These issues normally occur when you have a faulty circulation pump, air in the system or even a seized motor. If there are complex electrical faults, we highly recommend a professional diagnosis.
Airlocked Radiators
If your radiators aren’t heated enough, they can trap air. This boiler breakdown symptom can be addressed by bleeding the valve on the affected radiator.
Now use the radiator key to slowly turn the valve counterclockwise to release the air until water starts to flow consistently. Next, you need to check the boiler pressure as it might have dropped and require refilling.
Power Supply Issue
Many times, a boiler not turning on is simply because of a tripped switch, blown fuse or any other electrical issue.
Power supply issues can include a boiler display flickering, no response when pressing power ignition., fuse keeps blowing, boiler works sometimes and sometimes it doesn’t.
It is suggested to consult a professional when dealing with power supply issues of a boiler.
Faulty Diverter Valve
A gas boiler not working correctly because of a faulty diverter valve is easy to spot. If your hot water works but your heating doesn’t, then this issue is because of a faulty diverter valve.
Consider getting the services of a boiler engineer who can get you rid of all the worries.
Sludge or Debris Build-Up
Debris in your boiler system can cause poor heating and is one of the long-term boiler faults. You can solve this issue by power-flushing, which clears the sludge and improves your boiler’s efficiency.
Symptoms include radiators remaining cold at the bottom, overheating boiler, repeated shutdowns and circluation pump failures. Furthermore, the heating system may take longer than usual to warm up. This is followed by dark or dirty water when the radiators are bled.
It is strongly suggested to consult a heat engineer for performing a chemical flush or power flush. A heat engineer can also add a corrosion inhibitor and a magnetic filter for preventing any future buildup.
Old or Worn-Out Boiler
Older boilers may face consistent boiler problems, and solutions may become too costly. An easy fix is to upgrade your boiler.
When going for a new boiler purchase, choosing a reliable cover for unexpected repairs is paramount for getting rid of most of the problems.
Prevent Boiler Problems with Regular Servicing
A boiler not working doesn’t just leave you without heating, it disrupts your comfort, damages pipes and can cost a considerable amount in emergency callouts.
Most of the breakdowns happen suddenly, but here’s a truth few homeowners realise: 5.1% of English household boilers broke down over a decade, most often due to inconsistent checks.
This means that a lot of homeowners each year face emergency repairs that could have been prevented.
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FAQs
Why do boilers tend to fail more in winter?
Boilers work harder when it’s cold. This exposes them to issues like low pressure, sludge build-up and frozen pipes.
Does skipping annual servicing reduce boiler efficiency?
Getting your boiler serviced on time helps maintain efficiency, minimize the fuel usage, and extend lifespan.
Do emergency boiler repairs cost more?
Emergency services can be priced higher depending on response time and labour.
How long does it take to diagnose a boiler issue?
Problems can be diagnosed within an hour by a certified engineer.
Will a repair affect my boiler’s warranty ?
Only if you got your boiler repaired from an unqualified person.
