Noisy boiler?
Some sounds are perfectly normal for a boiler to make when it’s working hard heating your home and hot water.
You can expect to hear some sounds from the pilot light being ignited, or the pump circulating water around your heating system – and these aren’t any cause for alarm.
But if you’ve suddenly noticed your boiler making unfamiliar, loud or strange noises, they could indicate a problem, and are a cause for concern.
If it sounds like an aeroplane is taking off in your utility room, or your boiler is banging, whistling, or gurgling, you’ll want to get to the bottom of what’s going on – and fast.
You should never ignore warning signs that your boiler is on the blink, because it could pose a safety risk. But even if it isn’t a dangerous fault, ignoring a problem will result in a more expensive repair bill, or worse, down the line.
In this guide, we explain some of the possible causes of some common, but abnormal noises, that might be coming from your boiler.
Where’s the noise coming from?
First things first, where’s the noise coming from? Whilst this might sound like a stupid question, sometimes noises may travel and echo through your heating system.
The noises might not be coming directly from the boiler itself, but rather from your pipes, radiators or a tank or cylinder.
It’s easier to identify the problem when you pinpoint precisely where the noise is coming from.
Check for a fault code
The next step is to check whether your boiler is showing a fault code.
Most modern boilers, particularly combi boilers, have a digital display which will show a boiler fault code when your boiler encounters a problem. The code helps to identify the cause of the problem and indicates what action should be taken.
All boilers display error codes differently, so depending on your model, the error code itself will vary.
If your boiler is showing a fault code, the first step to take, is to check your boiler’s manual.
Strange or unusual noises that your boiler might make
Here are the most common abnormal noises that you may hear from a boiler that has a problem:
- Gurgling noises
- Banging or whistling noises
- Whooshing noises
- Humming or vibrating noises
- Aeroplane or droning noises
If you hear any of these noises coming from your boiler, read on and we’ll explain what might be causing them.
1. Noisy boiler: Gurgling boiler noises
If your boiler is making gurgling noises, this could be a sign that air has become trapped inside the heating system and is mixing with the water. Thankfully, this isn’t usually a big problem, and can sometimes be resolved by simply bleeding your radiators.
Fixing the problem: bleeding your radiators
To bleed your radiators, you need to start by turning your heating off and allowing your radiators to cool. Place towels on the floor under your radiators and put a container under the bleed valve.
Using your radiator key, release air from the bleed valve by slowly turning it anti-clockwise to release air. You should hear a hissing sound as the air escapes.
Keep releasing air from the valve until you can no longer hear air escaping and some water begins to trickle out. When this happens, close the valve quickly.
Once you have released the trapped air from your radiators, check your boiler pressure and switch the heating back on.
If bleeding your radiators has done the trick, that’s great. But if you’re still noticing gurgling sounds, you should contact a Gas Safe registered engineer for help.
2. Noisy boiler: Banging or whistling boiler noises
If your boiler is making banging or whistling sounds, chances are you’re experiencing ‘boiler kettling’. It’s called ‘kettling’ because it sounds like a kettle boiling, and it’s a common cause of a noisy boiler.
Not only does a kettling boiler sound like a boiling kettle, but it’s also much the same process behind it!
Despite the misleading name ‘boiler’, the water in your boiler shouldn’t actually boil. Water is typically heated to around 70 °C before being pumped around your home to be used by your radiators and hot taps.
But if the flow of water is slowed down for some reason, the water can heat too quickly and reach boiling point (100 °C).
If this happens, steam is generated, and air becomes trapped in your heating system. You’ll start hearing whistling, banging, popping and gurgling sounds.
There are several reasons why water might be being pumped around at a slower rate and reaching boiling point:
Possible cause of kettling: Limescale build up
Limescale build-up is one possible cause of kettling, and it’s a common problem for homes in hard water areas.
When limescale and ‘sludge’ accumulates in your heating system’s pipes, it will block the flow of water. By slowing the flow of water, it can be overheated by your boiler – causing kettling sounds.
Pipes blocked by limescale and sludge is also a common reason for your radiators developing cold spots.
Possible cause of kettling: Faulty thermostat
Another potential cause of kettling could be a faulty thermostat. A broken thermostat can give an incorrect reading to your boiler, causing it to over-heat the water.
Possible cause of kettling: Damaged pump
Another possible culprit is if your boiler pump is damaged. The boiler pump’s job is to push water through your heating system at the right speed to heat the water to the correct temperature.
If the pump develops a fault, it’s likely that water will be pushed at a slower rate, and will be overheated by the boiler.
How to stop boiler kettling
Boiler kettling is not something you can deal with yourself. It can be dangerous, and you should call a Gas Safe engineer to investigate what the cause of the kettling is.
If the cause of the kettling is limescale or sludge build-up, a chemical clean or power flush should do the trick. But if you have a faulty part, such as the pump, this may need to be replaced.
3. Noisy boiler: Whooshing boiler noises
Whooshing or vibrating noises from your boiler can be alarming, but thankfully the problem is usually with the air supply and sounds much worse than it is.
There are two common reasons for whooshing noises originating from a boiler.
Possible cause of whooshing noises: Air intake pipe blockages
The first common cause of whooshing sounds is a blocked air intake pipe. The air intake pipe is attached to the back of the boiler and leads outside of your home. If dirt and debris block the pipe, this can cause a whooshing sound.
Possible cause of whooshing noises: Air filter blockages
The second common cause of whooshing noises is a blocked air filter. Air filters are usually located inside your boiler. They can get blocked up by the buildup of dust and debris. If this happens, the passage of air is blocked, creating a whooshing sound.
How to stop whooshing noises
Whether the issue is with the air intake pipe or the air filter, you should call a Gas Safe engineer to fix the problem.
4. Noisy boiler: Humming or vibrating boiler noises
If your boiler is humming or vibrating, there are a few potential causes for this, including the following:
Possible cause of humming noises: Water pressure that is too high
High pressure is one of the biggest culprits of humming or vibrating noises. You can use the pressure gauge on the front of the boiler to check that the pressure is under 1.5 bar when the radiators are cold.
Possible cause of humming noises: The boiler’s pump is seized up or is running too fast
Another common culprit of a humming boiler is a problem with the boiler’s pump. If it has seized up or is operating too fast, it can cause vibrations and humming.
Possible causes of humming noises: A loose component such as the bearings on the boiler fan
Another issue that can create a humming noise is if the bearings within your boiler fan are on the way out.
How to stop humming noises
If the humming is caused by high pressure in your heating system, you may be able to resolve this by reducing the pressure by removing some of the water in the system.
If this doesn’t work, or it’s not a high pressure issue (you’ve checked your pressure gauge), you will need to contact a Gas Safe engineer for help.
5. Noisy boiler: Aeroplane or droning noises
One of the more disconcerting boiler noises is when your boiler sounds like a drone or aeroplane is taking off. The usual cause of this is a faulty pump.
How to stop aeroplane or droning noises
The most common resolution here is to have a broken boiler pump replaced. You should contact a Gas Safe engineer as soon as you hear your boiler making an aeroplane or a droning noise.
How to avoid boiler noises
Prevention is better than cure, so to avoid having problems in the future, you should ensure that you have your boiler serviced annually by a Gas Safe engineer.
Regular servicing reduces your chances of developing noisy faults because any required maintenance will be carried out proactively.
Research by Which? Found that around two thirds of boilers that are serviced every year never need a repair. This number drops dramatically as you increase the time between services, so spending a bit on a boiler service could potentially save you a much bigger repair bill in the future.
Final thoughts
Hopefully this article has helped you to understand your boiler a bit better, and you may have identified a possible cause of a strange new noise.
It may be that there’s a quick fix to your problem. But unfortunately, boilers don’t last forever.
If your boiler is in its golden years; is out of warranty; or always seems to be on the blink – it might be time to consider a boiler replacement.
Why not contact The Heating People to book your free survey?
Steps to your new boiler…
The first and most important step in getting a boiler replacement is to find an expert engineer that you can trust. This task is crucial for two main reasons.
A new boiler installation involves many tasks. These cover the lead up to the installation and the installation itself.
Your expert engineer will attend at the time and date agreed, to carry out a survey of your home.
Following the free survey of your home, The Heating People will send you a fixed price quotation, with options to allow you to choose a boiler that’s right for you.
Once you’ve decided you want to go ahead with the works in your quotation, we’ll arrange a convenient date to complete the work.
Once your heating engineer arrives to install your new boiler, they will discuss the planned work, to ensure that everyone is happy with the plans. They will explain where they will need access to, and for how long, so that you can plan your day.
Depending on what was discussed during the quotation stage, your engineer will use the
Your engineer will then install your new boiler, the boiler flue, and make all the pipework connections.
Your engineer will then complete a handover with you when all the work is complete. This ensures that you are as informed as possible on how to operate the boiler, how to use all the controls, and how to get the best efficiency from your system.
The Worcester Bosch Greenstar 4000…
We reckon that even if you’re not familiar with their boilers; you’ll have at least heard of the manufacturer,
New for 2021, the Greenstar 4000 is the new and improved successor to the hugely popular Greenstar i.
Available in
The Worcester Bosch Greenstar 4000 is A-rated for energy efficiency, with an impressive 94% efficiency.
Worcester Bosch have designed their new Greenstar 4000 to be a ‘SimpleSwitch’ for customers who have an existing Greenstar i; i Junior; or Si boiler (2005-2015 models).
Worcester Bosch provides hefty 10-year warranties. So that you can have peace of mind that should anything go wrong, you’ll be covered.
The Greenstar 4000 is Worcester Bosch’s mid-range boiler, sitting between the
The Greenstar 4000 can produce up to 12.3 litres of hot water out of your tap in a minute. And operates extremely well in low water pressure areas, ensuring powerful and warm showers.
But what we really want to know is, how the Greenstar 4000 compares to its predecessor, the best-selling Greenstar i.
We hope you’ve found this blog helpful.
Under section 11 of the Landlord and Tenant Act 1985; as a landlord you are responsible for keeping the following in repair and proper working order – supply of:
As a landlord, it’s your responsibility to maintain and repair the heating in your rental property; under Section 11 (c) of the Housing Act 1985.
Obviously, you can’t be liable to carry out any repairs until you’ve been told about the issue by your tenant.
Maintaining central heating and hot water is an important part of keeping your property free from hazards.
The HHSRS introduced 29 categories of housing hazard. In terms of heating, you should be aware of the following particular hazards:
Under the Gas Safety (Installation and Use) Regulations 1998; as amended by the Gas Safety (Installation and Use) (Amendment) Regulations 2018; you are under a statutory duty for the safety of your tenants in relation to gas safety.
During a gas safety check, our engineers will check that your appliances are:
The Domestic Minimum Energy Efficiency Standard (MEES) Regulations set a minimum energy efficiency level for domestic private rented properties.
If you have an external condensate pipe or an outside tap at your property; make sure it has a foam sleeve around it to prevent any issues when the temperatures drop.
If your property has a fireplace or log burner; you need to have your chimney swept at least once per year. This will ensure that carbon deposits are removed, minimising the risk of a chimney fire.
It’s important that you test smoke alarms and CO alarms at least once per year. There must be a working smoke alarm on each floor of the property.
If your heating is on, but you’ve got no hot water, it’s easy to get into a panic.
Forgive us for pointing out the obvious, but the first thing to do when your hot water goes off, is to check that your boiler’s working.
Some hot water problems are not actually caused by a fault with your boiler. It could be that there is a problem with the supply of your electricity, gas and water.
If your boiler’s hot water is controlled by a
Similarly, to checking your timer, you should also check your boiler’s thermostat.
Ah – the classic: have you tried switching it off and on again?!
Another reason why you might not be getting any hot water is if there’s no pilot light on the boiler or the boiler pilot light keeps going out.
If you have a sealed system or
If your hot water has suddenly gone off when it’s freezing outside, there’s a good chance that your
A leak somewhere in your heating system can cause the pressure to drop, which can stop your hot water from working.
If you’ve experienced a sudden problem with your hot water, it’s very unlikely you’ll need a new boiler. As you can see from above, there is often a cheap and quick fix to the dreaded no-hot-water situation.
We hope that this guide has been useful in helping you to troubleshoot some of the simpler causes of having no hot water.
10 Tips for keeping your home warm this winter
You wouldn’t dream of driving your car without a valid MOT; and you should think of your
The last thing you want when you’re paying to heat your home; is for all the
As well as losing heat through gaps around your windows and doors; heat also escapes through your roof and walls through conduction and convection.
Insulating your water pipes is called ‘lagging’ and by sealing in heat; it saves energy and prevents pipes from freezing and bursting in the winter.
If you have a hot water tank, check its insulation. Most hot water cylinders have some insulation; but if your tank has a jacket under 25mm thick, it could benefit from top-up insulation.
A common problem with radiators is that air can get trapped inside them; meaning that they don’t heat up properly. And your boiler will be working much harder to warm up your home.
Do you dry clothes by hanging them on your radiators? If so, stop! If you want your radiators to be able to heat your rooms effectively, they need to be unobstructed!
You’ve probably got a room (or rooms!) in your house that don’t get used as much as the others. If so, you’re wasting money on heating these rooms to the same temperature as the rooms you use all the time.
If your radiators still have cold spots or feel cooler than usual; and bleeding them hasn’t worked, your heating system might need a
Your
Heating controls
Unfortunately, boilers don’t last forever. If you’ve noticed your boiler is struggling to do what it used to do; or is breaking down regularly; or is not working at all; you might be wondering whether you should try to repair what you have; or
Nest Smart Learning Thermostat…
Like other smart thermostats, the Nest thermostat allows you to schedule your heating, with the promise of saving you energy, and therefore
Since Nest is a learning thermostat, it learns the temperatures that you like when you’re at home and then programs itself.
A Nest thermostat can help you to save energy by indicating (with a leaf symbol) when you’ve adjusted to an energy-efficient temperature.
It’s clear that a Nest thermostat can help you to save energy, but how much money could this save you?
When you buy a Nest Learning thermostat, you get two components: the smart thermostat and the Heat Link, which connects to your boiler.
Nest recommends that installation should be carried out by a professional.
Let’s start with the superficial stuff – it’s pretty, right?!
As we mentioned earlier, once you connect your thermostat to Wi-Fi, you can control it from anywhere. So, if you’re on your way home from a weekend away, you can adjust your temperature at home so that you arrive back to a lovely warm house.
As we’ve mentioned above, Nest has motion sensors which allow it to switch to Away mode when you go out, which will save you energy.
Nest now has OpenTherm technology. OpenTherm is a language that compatible thermostats and heating systems can use to talk to each other with two-way communication instead of simple one-way on/off commands from the thermostat.
Although the Nest thermostat is one of the best-known smart thermostats on the market, there are some drawbacks.
The Nest Thermostat remains one of the best and simplest smart heating systems available.
Thinking of replacing a
First off, it’s important to establish what your existing heating system is, and what you’re looking for.
Heat-only boilers are often thought of as the traditional way of heating a home. And out of the three types of boiler available (heat-only, system and combi) they take up the most space.
Since heat-only boilers store large quantities of hot water in a cylinder; they can meet a high demand for hot water.
If you’re thinking about switching to a combi boiler, you’re probably already aware of the drawbacks of a heat-only boiler.
Combi boilers are currently the most popular type of domestic boiler installed in the UK. We’ve dedicated a whole blog to what they are, which you can read in full
Combi boilers are very popular in the UK because they offer a lot of benefits:
Thanks to the
If you’ve currently got a heat-only boiler; you might have had occasions where you’ve used all of the hot water in the cylinder; and have had to wait for it to refill.
It sounds counterintuitive to say that a combi will never run out of hot water; and then say that it can’t meet high demands for hot water – but stay with us!
Installation
The
If you’ve decided that you want a combi boiler, your next challenge is
We hope you’ve found this guide useful in helping you to decide whether switching from a heat-only to a combi boiler sounds like a good option for you.
If you’re
A
The
We’ve dedicated an entire blog to the Greenstar 8000 LifeStyle range, which you can read
The second offering in the Lifestyle range, is the Greenstar 8000 Style, and it’s the premium offering from Worcester Bosch.
The popular Greenstar 4000 is available as a system boiler in 12kW, 15kW, 18kW, 21kW and 24kW outputs.
The Worcester Bosch Greenstar 8000 Life and Style boilers are available as system boilers in 30 and 35 kW power outputs.
A heat-only boiler is also known as a regular or conventional boiler. They are seen as being the traditional way of heating a home. They are usually installed as part of an unvented system, but they can be sealed too.
If you liked the look of the Worcester Bosch Greenstar 8000 Life combi boiler, but you need a heat-only boiler, you’re in luck!
Another good option in the heat-only range is the Worcester Bosch Greenstar Ri.
If you’re confused about what type of boiler you need, you should start by thinking about your heating and hot water needs.
If you’ve read our related blog:
Common combi fault codes…
Although there are many different fault codes that your boiler can display (in different combinations), there’s no need to panic when a code starts flashing.
Problems can arise, triggering a fault code, if your boiler is not receiving gas or if the gas pressure is too low.
If your boiler has stopped working when it’s freezing outside, there’s a good chance that your boiler’s
It is extremely important that you only perform actions on your boiler if your boiler manual instructs you to do so.