How do I know my boiler isn't working efficiently? Here are the main warning signs that a gas boiler isn't working efficiently.
Black stains around or on the boiler
The flame burns yellow instead of blue
The indicator light stays off
Takes a long time to heat up
poisoned by carbon monoxide
Your boiler is the hub of your central heating system. Therefore, it is crucial to have an efficient and reliable boiler. Not only to keep your house warm and provide you with constant hot water, but also for the safety of your family.
A malfunctioning boiler is not only an inconvenience, it can also result in a huge expense. Annual maintenance on your boiler will help keep it safe and in good working order. Between repairs, there are many signs that something is wrong with your boiler.
We've listed some signs below. If you notice any of these signs then it is recommended that you hire a Gas Safe registered engineer to repair your boiler and rectify the problem, or install a new boiler for you if required.
If black stains start to appear on or around the boiler, this is a sign that there may be a leak in or around the flue.
Boiler exhaust leaks can be fatal, see Carbon Monoxide Poisoning below.
When you look at the flame inside the boiler, it should be burning with a blue flame. If it burns with a yellow flame, it may indicate that carbon monoxide is being produced.
The most common reason for the pilot light to go out is that the thermocouple needs to be replaced. The thermocouple is a small probe that extends into the flame of the pilot light.
It has a small diameter metal wire that connects back to the gas valve. Always contact a Gas Safety Registered Engineer to resolve any issues with your boiler.
Modern boilers that work efficiently can heat and produce hot water almost instantly. If you notice hot water flowing to your taps or your house taking longer than usual to warm up, then this should tell you that your boiler needs a check.
Carbon monoxide is often called the "silent killer" because it is a colorless, odorless gas that is difficult to detect.
Low levels of carbon monoxide in the body can produce flu-like symptoms such as nausea, dizziness, and headaches, but as levels increase, symptoms can become more severe, such as increased difficulty breathing, and in some cases, carbon monoxide poisoning can lead to death.
As mentioned above, there are some signs you can look out for that your boiler may be producing carbon monoxide, but we recommend that you install a carbon monoxide detector as this is the best way to detect elevated levels of carbon monoxide. They are now widely available and can be tested as part of an annual boiler service.
These are the main warning signs that a gas boiler is not working efficiently.