FGHRS or ‘Flue Gas Heat Recovery Systems’ are energy saving devices. They allow your boiler to reuse or ‘recycle’ heat that would otherwise be wasted as gases out of the flue.
We know that recycling is good for our wallets and the planet; so it probably won’t surprise you to learn that it’s good for our boilers too!
This means that you’ll need to burn less fuel to heat your home. Thereby saving you money on your energy bills, whilst also reducing your carbon footprint.
Using FGHRS is one of the four ways that new combi boilers can comply with the ‘Boiler Plus’ legislation.
Read on to find out everything you need to know…
What does Boiler Plus say about FGHRS?
Boiler Plus is a new (ish) set of rules on energy efficiency; which improves the way we use energy in our homes.
From April 6th, 2018, all boilers must now have a minimum ErP (Energy related Products) rating of 92%. And all gas and oil boilers must have appropriate time and temperature controls fitted.
In addition, when installed, combi boilers must have one of four energy saving devices fitted – one of which is FGHRS.
So, if you’re in the market for a new combi boiler; a boiler with this energy saving device might be a good option.
Some combi boilers have FGHRS built-in
In some cases, you don’t even need to consider whether to add FGHRS as an add-on to your boiler; because the boiler itself comes with the technology built-in.
You might like our related blog: How to choose an energy efficient boiler.
What is FGHRS?
FGHRS are energy saving devices that make boilers more efficient by capturing and reusing the waste heat from your boiler. This would otherwise have escaped out of your flue or chimney.
Your boiler produces fumes when running. A flue takes these fumes safely out of your home through a wall or your roof.
The flue gases are hot, and letting them go straight out into the atmosphere is a waste of up to 35% of the heat that your boiler is producing.
A boiler with FGHRS recycles hot flue gases that would otherwise be wasted to preheat the cold water entering the boiler.
Before the hot gases go outside; they go through a heat exchanger, where incoming cold mains water gets warmed up by the gases. This lowers the amount of energy needed to warm the water up for your heating system.
In the time it takes for the incoming water to pass through the heat exchanger; the water temperature rises from around 10°C; to between 20-40°C.
This means that your boiler doesn’t have to work as hard to heat the water. The much cooler flue gases are then vented out.
What are the benefits?
Lets take as look at what you stand to gain from this energy saving device:
FGHRS reduces your fuel consumption – and therefore your energy bills
Where FGHRS is fitted on a modern boiler, it will need to burn up to 7% less gas. But will deliver the same amount of heat.
This is because the cold water is being ‘pre-warmed’ by gases which would otherwise have been wasted. So, your boiler isn’t having to use as much energy to get cold water hot.
If FGHRS is added to an older non-condensing boiler, the fuel savings are even more significant. You could save up to 52% on a G rated boiler, and up to 35% on an older combi boiler.
By reducing your fuel consumption, you’ll reduce your energy bills.
FGHRS reduces your carbon footprint
As well as saving you money on your energy bills; using FGHRS will also reduce your carbon footprint, which is good news for the planet too!
The Boiler Plus regulations; which recognise FGHRS as being one of four important energy saving devices; were created as part of the government’s strategy to reach net-zero by 2050.
As part of the consultation process leading up to the implementation of Boiler Plus; independent tests were presented to the Government. They found that if half a million FGHRS were installed in homes; 56,209,150m3 of gas would be saved; and 114,734,118kg of carbon dioxide emissions saved.
It’s a low maintenance option
It’s straightforward for Gas Safe engineers to fit FGHRS. And once installed, you can just forget about them, and let them do their thing!
Older boilers can have FGHRS fitted
Older non-condensing boilers do not have any sort of built-in FGHRS. And their efficiency can be as low as 65%, which means they’re bad for your wallet and the environment.
If you have an old G-rated model, you’re probably best replacing it with a new boiler.
But it’s possible to increase the efficiency of your current boiler by attaching FGHRS.
If you choose this option, you’ll need space above your existing boiler to fit the system. These systems cost around £600. But according to the Energy Saving Trust, you could save up to £100 on your fuel bills each year.
If you’re thinking about a boiler replacement, contact us today for tailored advice on what the best options are for you.
How much do external ‘add-on’ FGHRS devices cost?
External or ‘bolt-on’ devices can cost from £500 – £800, depending on the type of boiler you already have.
Whilst you will see energy savings, it may take many years to recover this cost.
It might be a better option to consider replacing your old boiler with a more efficient one with integral FGHRS; such as the ATAG and Vaillant models we mentioned earlier.
A like for like replacement of an older combi for a new combi with built-in FGHRS; starts from £2500, depending on your current system, and chosen model.
To discuss your options, contact one of our friendly team at The Heating People.