What is a back boiler fire, why are they now illegal and what are the replacement options?
Back boilers or back boiler units are a type of central heating system that was invented in the 1960s and reached their peak of popularity during the 1970s and 1980s.
This compact boiler is installed behind the mantle of an open fireplace and uses the heat from the fire to heat the home and provide hot water.
However, as less expensive and more efficient modern boilers came into existence, back boilers lost favour.
PS We fit new boilers with gas safe installation nationwide. Simply answer these questions, get your fixed price and you could get it installed as quick as tomorrow.
Since the 2005 Building Regulations were issued, back boilers have been illegal in the UK.
Also, the government legislation called Boiler Plus, which came into effect in 2018, prohibited the installation of new back boilers.
This was primarily because back boilers do not meet government safety regulations and owing to their significant carbon emissions.
Back boilers can no longer be employed for newer installations.
Additionally, obtaining broken parts has become difficult and expensive owing to the ban, with few companies manufacturing replacement parts.
Consequently, most homeowners who own back boilers are looking for newer, more affordable, and more energy-efficient alternatives.
What Is A Back Boiler Fireplace?
Back boilers are also known as wetback heaters or wetback stoves.
They are attached to the back of a fireplace, chimney, or stove.
Initially, back boilers attached to a fireplace or chimney were more common.
However, boilers attached to stoves became the norm later.
Back boilers were used as the main heating system or as a supplemental heating source.
They were designed to use the exhaust heat from fireplaces, chimneys, and so on.
This is the energy that you otherwise lose up the chimney.
How Do Back Boilers Work?
Knowing about boiler functioning gives you a clear understanding of the heat exchange mechanism, efficiency, and more.
Back boilers are usually built behind a fireplace or a gas fire unit. They make use of the exhaust gasses and here is how they function.
Back boilers have a cold water inlet source located at the bottom.
The hot gasses that pass through the flue heat the heat exchanger, which is located at the end of the burning chamber.
The heat exchanger then heats the cold water. It then delivers the heated water to the output via an electrical pump.
To prevent pressure build-up, the hot water is reserved in a hot water cylinder that has an overflow vent.
Back Boiler Efficiency
The initial back boiler designs were not that efficient; however, later, the boilers were engineered to provide high efficiency.
While the earlier models were less than 70% efficient, the later models could provide around 80% efficiency.
However, they still cannot compete with the 90% and higher efficiency that many new combi boilers provide.
Pros And Cons Of Back Boilers Fires
Some advantages and disadvantages of back boilers are:
Pros
They take up less room and can be easily tucked away out of sight, making them ideal for small homes
Less expensive
Provide both room heating and hot water for domestic use
Can be used as a supplementary heat source for more efficient room heating and less load on either system
Can be connected to the central heating system, so you do not require an immersion heater to heat your home
When properly serviced and cared for, back boilers are quite reliable
Cons
The biggest drawback is their low efficiency. While modern boilers can provide up to 98% efficiency, back boilers can provide maximum efficiency of 80%. This greatly affects your carbon footprint and energy consumption, especially if you live in a cold climate
They are incapable of supplying instant hot water
Back boilers need ventilation as they are open-flued. In case of poor ventilation, where there is no access to fresh air due to problems with the boiler or the chimney flue, toxic fumes like of carbon monoxide can build up in your home, leading to serious health hazards
The same ventilation system, however, becomes the source of draughts and noise
As the boiler depends on the chimneys for ventilation, renovation plans are very limited
Also, with the British Government making it mandatory for new boilers to have a minimum efficiency of 86%, installing new back boilers is out of the question
Risks Associated With Back Boilers
Back boilers pose a high-risk factor when left unused for a long time. In the last 5-years, there have been several untoward incidents— 3 cases of serious injuries and one fatality.
This happens because old boilers may not get completely drained when you discontinue using them.
So, when they are reused, the residual water gets heated up and creates pressure, which may cause the boiler to explode.
Also, as the fireplace is situated close to the boiler, the heat and gas trapped in the fireplace without a flue system can affect the boiler (not in use, but not dismantled) and cause it to explode.
While these are rare occurrences, if you observe any overheating or other problems with the boiler, it is recommended to be cautious and consult a heating engineer.
Why You Should Replace Your Back Boiler
Back boilers were all the craze at one point in time, and although better solutions are available today, many homes still rely on this ancient technology.
If you haven’t retired your old friend yet, here are some reasons why you must think about it:
Back Boiler Safety Issues
Back boilers have a life expectancy of 20 to 30 years.
As already discussed, the risks associated with back boilers highly increase with age.
And as the last installations were somewhere in the 1980s, even they have reached the end of their course.
Also, with discontinued production and decreased usage, replacing damaged boiler parts has become very difficult, and sub-par servicing is often the only option. This increases the risk further.
Also, back boilers are constantly expanding and contracting. Although this is not a safety hazard, it may cause structural problems to the home.
Back Boiler Energy Efficiency
While there are no regulations on the old boilers, the newer regulations only allow the sale of boilers with high efficiency.
So, while your old back boiler will provide less than 70% efficiency, you have better options that can provide 90% or more efficiency.
This way, you save a lot on energy bills and heating bills.
Modern Renovations
Back boilers are permanent fixtures that require a fireplace close by.
This highly limits renovation plans and can significantly bring down the aesthetics of a home.
Although they are out of sight, back boilers are still space-consuming as they require both hot and cold water tanks, a requirement that modern options like combi boilers can eliminate.
They are aesthetically pleasing, easy to install, and compact systems that take up very little space.
Back Boiler Alternatives
When your back boiler system is broken, or you cannot find a damaged part, it is time for a replacement boiler.
Also, even if your boiler is working just fine, it is still better to replace it as there is a great risk factor associated with old back boilers, and they have very low energy efficiency.
When looking for boiler replacement options, the most common and the best ones are:
Combi Boilers
Combi or combination boilers are the latest trends. They are compact boilers and do not require any storage tanks.
They heat the house as well as provide hot water. Also, as they heat the water on demand, they are highly energy efficient.
However, they are suitable for smaller properties that do not have 2 to 3 baths running simultaneously.
System Boilers
They are suitable for large homes with high hot water requirements. They require more space as they have a hot water storage tank.
However, as they store heated water, the system can readily provide hot water to two or more baths simultaneously.
Regular Boilers
They are the highest space consumers, with two tanks—one for hot water storage and another for cold water storage.
They are one of the oldest types of boilers, also called conventional or traditional boilers.
They are heat-only boilers, meaning they will heat the house but will not heat water for domestic usage.
Back Boiler Fires Conclusion
Back boilers enjoyed their time of popularity.
However, their use has significantly decreased as a result of better alternatives and government restrictions.
Only very old houses have them.
In light of the low energy efficiency and high level of risk associated with back boilers, it is advisable to replace them with combi boilers, system boilers, or regular boilers.
Looking for the best deal on a new boiler?
If you’re aiming to get the best deal on a new boiler, consider getting a quote from us, here’s why:
Gas Safe installation within 24 hours.
Thousands of satisfied customers with an average score of 4.9 on Trustpilot, surpassing the market leader.
Which? Trusted Trader: Heatable is proudly recognised as a Which? Trusted Trader.
Price match guarantee: We will match any like-for-like cheaper quote.
Flexible payment options, including interest-free finance.
Up to 12-year guarantee on selected boilers.
Fixed price guarantee: No hidden costs.
Save your quote and decide later.
Get an instant fixed price on a new boiler, here.
To learn more about boilers, visit our advice section, check out our YouTube channel, or read customer testimonials here.
Heat Happy.
