0151 792 6245

Open Mon-Fri 8.30 to 5pm

Energy efficiency

7 ways to improve your boiler’s energy efficiency

7 ways to improve the your boiler’s energy efficiency…

If you want to reduce the money you’re spending on your fuel bills – and frankly, who doesn’t?! – improving the efficiency of your boiler is the answer.

This is because an efficient boiler gets the maximum heat energy out of the fuel it burns (usually gas), helping to reduce your fuel bills and lower your carbon emissions.

So, you can feel good that you’re not only saving money, but you’re helping the planet too!

And if you’re thinking that you already have an efficient boiler, stay with us – because unfortunately many ‘efficient’ boilers run 10-25% under their A-label efficiencies.

This is often because they’re the wrong size; haven’t been set-up properly; or they’re being used in an inefficient way.

In this blog, we’ll look at 7 ways you can improve your boiler’s efficiency, and hopefully save money.

What is boiler efficiency?

To start with, what do we mean by ‘boiler efficiency?’ Unfortunately, no boiler is 100% efficient.

A boiler’s ‘energy efficiency’ refers to the percentage of the total energy (fuel) used by the boiler to provide heating and hot water.

You can think of boilers as being a bit like cars. You know that if you put the same amount of petrol into two different models of car, you probably wouldn’t be able to drive the exact same distance in each.

One may be less energy efficient, or a ‘gas guzzler’!

Old boilers are generally gas guzzlers. They need to burn lots more fuel to produce the same amount of useful heat as their modern counterparts.

How do we measure boiler efficiency?

Since 2015, boilers have been given a rating from A-G under the European energy label ‘ErP’, which stands for ‘Energy-related Products’.

Under this scale, boilers are rated from A-G, with A being the most efficient, and G being the least efficient.

All new boilers must be A-rated for energy efficiency under the Boiler Plus regulations.

So that we can better understand what boiler efficiency is, and how it’s measured, let’s compare two different boilers.

Our first boiler is a modern a-rated model with an impressive 92% efficiency. Our second is an old G-rated boiler with 60% efficiency.

With our A-rated model, 92% of the energy (or fuel) used by the boiler produces useful heat for the home, and only 8% is wasted.

But with our ‘gas guzzling’ G-rated model, only 60% of the energy used produces useful heat for the home, and a staggering 40% is wasted.

So, you can see how important the energy efficiency of your boiler is when you’re trying to save money on your fuel bills!

Why are older boilers less efficient than modern ones?

A zombieIf you were surprised by our comparison of the A-rated versus the G-rated boiler, you might be wondering why it is that older boilers are so much less efficient than their modern counterparts.

The reason for this is that all modern boilers now have condensing technology.

A condensing boiler works by recycling the wasted exhaust gas that is created during a boiler’s normal operation.

By re-using the exhausted gas, water vapour and steam back through the system, some of the heat and water is retained making the boiler’s operation more efficient.

A condensing boiler can typically extract 90-92% of heat from fuel, compared to 50-80% that a non-condensing boiler can.

If I buy a new boiler, will I definitely make savings?

Unfortunately, the answer to this is – it depends.

If you’re swapping a G-rated boiler for an A-rated one, you’ll certainly see a huge difference on your fuel bills.

According to the energy saving trust, you could save as much as £340 a year on your gas bill if you’re trading in an old-style non-condensing boiler for a new condensing one.

If you’re replacing a boiler that’s not quite as old as a G-rated non-condensing boiler, you obviously won’t see as much of a difference.

And what you also need to understand here is that just because your shiny new boiler is A-rated on the box, doesn’t necessarily mean that it will achieve this maximum efficiency potential.

It’s a sad fact that many new boilers run 10-15% below their efficiency capability.

The main reason that new boilers are failing to meet their potential is because they’re not able to run at the lower temperatures that they need to hit what you could describe as their ‘sweet-spot’ in condensing mode.

There are a number of reasons why boilers are prevented from getting into their condensing stride which enables them to save energy for you.

7 Ways to improve your boiler’s energy efficiency

Now we know why the energy efficiency of your boiler is important; let’s look at how we can improve it…

1. Improve your boiler’s energy efficiency with an expert installer

The first (and most important way) to maximise the energy efficiency of your boiler is to have it installed by an expert to begin with.

Unfortunately, lots of installers oversize boilers for their customer’s homes; configure them poorly; and provide sub-standard controls.

It doesn’t matter how efficient your boiler is on the box, if it’s thrown on the wall by a Charleton.

To go back to a car analogy, if the best race car in the world is fine-tuned by a complete novice, and then put on the wrong track, it’s not going to perform as it should. And that wouldn’t be the car’s fault!

The same is true for a boiler.

How boilers should be sized

It really grinds our gears to see installers just using the physical size of your property and the number of radiators you have, to determine boiler size. This is completely inaccurate and isn’t following industry standards.

These installers will frequently choose a bigger than you actually need, ‘just in case’. This is a big problem when it comes to energy efficiency.

Oversized boilers heat up too quickly; run for a short time; and then will turn off; before the cycle starts again.

This constant stop-starting, or ‘boiler cycling’ uses more fuel, and prevents your boiler from getting into condensing mode.

So, your big boiler will have cost more for the initial purchase; will cost you more in fuel; and will potentially cost you on repairs and replacements, because this cycling will inevitably take its toll on your boiler.

Thankfully, you won’t find any of our engineers counting radiators or oversizing boilers.

We install boilers the right way, following the industry standard under Part L of the Energy Efficiency Regulations. This means that you’ll get the correct size boiler for your needs, that is able to perform to its A-rated efficiency potential.

To find out more about how to get the correct size of boiler for your needs, check out our related blog here.

2.   Improve your boiler’s energy efficiency with heating controls

You can have a very efficient boiler, but if it’s poorly programmed or has limited to no controls, you’ll be wasting lots of energy.

According to the energy saving trust, investing in a programmer, room thermostat and thermostatic radiator valves could save you £75 per year and 320kg of carbon dioxide.

Even the location of your controls can make a difference to the efficiency of your heating system.

For example, if you only have one thermostat in your home, which is in a room that is quite cool; it will be telling your boiler to generate more heat, when you’re already warm enough.

Smart controls

Smart controls offer even bigger energy efficiency savings, with some manufacturers promising energy savings of between 20-30%.

Tado says that its smart thermostat ‘will pay for itself within a year’ by reducing your heating bills by up to 31%.

Netatmo claims that its smart thermostat will reduce the energy you use by 37%.

According to Ofgem, a smart thermostat can bring savings of around £150 per year.  Ofgem (2014) estimates that a multi zoned heating system could save up to £400 on the annual dual fuel bill of £1385.

But all of these estimates assume that you previously left your heating on all the time, to maintain a constant temperature.

So if you already turn off the heating when you leave your home, you’re unlikely to save as much as the manufacturers claim.

Think about how you use your controls

As well as investing in heating controls (smart or otherwise) you should think about how you’re actually using them.

If you just turn your heating up to full blast in the winter, hoping for the best, this will waste energy because you don’t need the heating to be on full blast 24/7 to be comfortable, and you probably don’t need all your rooms to be at the same temperature at all times.

Government research has shown that turning down your thermostat by just 1 degree can save up to 10% on your heating bills.

So, if you want to be comfortable and save money, resist the temptation to turn your thermostat higher than your comfort level, and put an extra jumper on until your room gets to your desired temperature.

3.   Improve your boiler’s energy efficiency with an annual service

You wouldn’t dream of driving a car without having a valid MOT, and car manufacturers also provide a recommended process for car servicing too.

So, it shouldn’t be surprising that something as hard-working as your boiler also requires some upkeep.

An annual service by a Gas Safe engineer is vital to not only keep your boiler safe, by avoiding the risks of gas leaks; fires; and carbon monoxide poisoning; but in keeping it running smoothly too.

Over time your boiler will accumulate dirt and deposits making it less efficient and a breakdown more likely.

By having your boiler correctly serviced it will be fully inspected and any required maintenance can be carried out proactively, so you can detect any minor issues before they become major problems.

During your service, your engineer will ensure that the internal combustion areas are free of dirt and debris will improve the heat transfer, allowing your boiler to light more easily and burn efficiently, which can lead to lower heating bills.

4.   Improve your boiler’s energy efficiency by bleeding your radiators

This is a nice simple task that you can do yourself, which can help to improve your boiler’s efficiency.

Although they’re often overlooked, your radiators are just as important as your boiler in keeping you warm.

If you’ve noticed that your radiators are cold or have cold spots; or are making funny noises; this might indicate that air is trapped inside them, and needs to be released.

Otherwise, your radiators won’t heat up properly, and your boiler will be working much harder to warm up your home.

To bleed your radiators, you should start by switching your heating off and allowing the radiators to cool. While they’re cooling, prepare the area by putting a towel under the radiator and placing a container underneath the bleed valve on your radiator.

You can then fit your radiator bleed key to the bleed valve, which is found inside a round nut, usually at the top of your radiator.

Once you have fitted your radiator key to the bleed valve, slowly turn 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.

Once you have released the trapped air from your radiator, you need to close the valve quickly.

You should repeat these steps for all of your radiators that need bleeding.

You should finish by checking the water pressure gauge or indicator, which is usually on the front of your boiler. For most boilers, this should be set around the 1 bar.

5.   Improve your boiler’s energy efficiency with a power flush

If you’ve bled your radiators, and they’re still not getting hot as they should, your heating system may need a power flush to cleanse a build-up of ‘sludge’ from your pipes.

‘Sludge’ is the delightful term used to refer to all of the dirt and deposits which accumulate in your radiators and pipes over time.

This gunk prevents the hot water from circulating through your system as it should and prevents your boiler from heating your home efficiently.

You can’t really install a shiny new efficient boiler into a system of dirty and blocked pipes and expect it to do an efficient job of heating your home. So it’s a very good idea to get a power flush when you have a new boiler installed.

During a power flush, your engineer will connect a power flushing unit to your heating system. This sends water through your central heating system at high speed, dislodging any build-ups of sludge, rust and debris.

Your boiler and central heating will be far more efficient afterwards and  it should help to avoid bigger issues down the line.

6.   Improve your boiler’s energy efficiency by topping up the water pressure (if it’s low)

Modern boilers require constant water pressure to function properly. A pressure drop will under your boiler’s efficiency, and if left untreated can cause problems, such as the dreaded, no hot water, situation.

Topping up the water pressure is a straightforward task that you can do yourself to improve your boiler’s efficiency.

To check your boiler pressure, you need to look for the pressure gauge or indicator which will usually be on the front of your boiler.

If you have a digital gauge, you should see a flashing pressure reading, if there’s a low (or high) pressure warning.

If you have a hydraulic pressure gauge, the correct boiler pressure will be indicated with a green zone, and the maximum safe operating pressure with a red zone.

As a rule of thumb, the normal boiler pressure is between 1.0 and 1.5 bars. If the pressure in your heating system has fallen below 1 bar, it needs to be topped up.

Boiler pressure systems differ, so it’s always best to check your manual, to see if you can re-pressurise it yourself.

Re-pressurising your boiler means allowing more water to enter the system, from the water mains supply, through something called the filling loop. If in doubt, you should consult a professional.

7.   Improve your boiler’s energy efficiency by upgrading other parts of your home

Even if your boiler is working at its full efficiency potential, you may be losing heat through old windows or poorly insulated lofts and walls.  

If your heat is escaping from your draughty home, you’ll need to burn more fuel to keep your home warm and comfortable.

Although this isn’t your boiler’s fault, because it’s running efficiently, it’ll still be costing you money on your energy bills.

By making some home improvements, you can enhance your home’s overall efficiency.

According to the energy saving trust, an average semi-detached house that has no insulation, can see the following average savings on energy bills by making these simple changes:

  • £225 per year savings by insulating your walls;
  • £150 per year savings by adding 270mm of loft insulation;
  • £75-£85 per year savings by installing double-glazed windows;
  • £15 per year savings by draught proofing your chimney with a chimney balloon;
  • £20 per year savings by installing a letterbox cover on your front door;
  • £20 per year savings by installing an insulating jacket on your hot water cylinder.

Read our related blog: How to reduce heat loss at home.

Final thoughts…

We hope that you’ve found these tips helpful. You might like to read: 6 Top Tips for Buying a New Boiler.

If you’re looking to upgrade your heating system, call us today to book your free survey.

Useful Links:

Tado article about smart control savings

Which? Reviews on smart thermostats

Google comparison of smart thermostats

Government report on savings by making small changes

Government report on improving the efficiency of heating

Energy Saving Trust advice on reducing heat loss

Energy Saving Trust article on draught proofing.