James Elston
Published November 5, 2024
Choosing the correct boiler for your needs can be an arduous task. There are many considerations, like whether you need a condensing or a non-condensing boiler. Which one is better for you? Which is more efficient? Is one more cost-effective than the other? Which has lower running costs? Which is better for the environment?
In this article, we will answer all of these questions and more. We’ll explore factors that affect the cost of these boilers and their key differences to help you determine which is best for you.
Key takeaways:
- Condensing boilers have an energy efficiency of 90% and are more eco-friendly.
- Non-condensing boilers are no longer legal in the UK but can be installed when special exemptions apply.
- Non-condensing boilers have an efficiency of 78% and lower upfront costs but are more expensive to run in the long term.
Contents
- 1 Condensing Boiler vs Non-Condensing Boiler
Condensing Boiler Vs Non-Condensing Boiler – Which Is Better?
The consensus is condensing boilers are better than non-condensing. This is mainly due to their higher efficiency and carbon emissions.
Let’s take a deeper look into both of the systems and what each has to offer.
Condensing boiler
What are condensing boilers? Condensing boilers are extremely energy efficient, lightweight and can be wall mounted. They are also suitable for any home or business, depending on the boiler size.
The thing that sets condensing boilers apart is their secondary heat exchangers. This is how they work:
- The heat from the burner is sent to the primary heat exchanger.
- Hot air then travels through this heat exchanger, where it remains until the temperature increases.
- This heat is then transferred to radiators.
- Exhaust gases are then transferred to the secondary heat exchanger.
- More heat is extracted during this process, and the water vapour in the exhaust gas condenses into liquid.
- This heat is then used to preheat the returning radiator water.
- The water vapour from flue gases is condensed into acid water. This liquid is safely expelled via a condensate pipe.
What are the advantages and disadvantages of a condensing boiler?
While their efficiency is the most distinguishing feature, condensing boilers have many advantages, But as with anything, they also have a few disadvantages.
| Pros | Cons |
|---|---|
| Extremely energy efficient (up to 99%) | Complex internal systems |
| Requires less fuel | More parts mean a higher chance of a malfunction |
| Lower energy bills | High initial costs |
| Aligns with green standards | More expensive to maintain |
| Longer life span (with proper maintenance) | |
| Safe and reliable |
Meta Title: Condensing Boiler vs Non-Condensing Boiler | Eco Happy
Meta Description: Condensing boilers are more efficient and have lower long-term costs. However, some homes are only suited to non-condensing boilers. Read more here.
Condensing Boiler vs Non-Condensing Boiler
Choosing the correct boiler for your needs can be an arduous task. There are many considerations, like whether you need a condensing or a non-condensing boiler. Which one is better for you? Which is more efficient? Is one more cost-effective than the other? Which has lower running costs? Which is better for the environment?
In this article, we will answer all of these questions and more. We’ll explore factors that affect the cost of these boilers and their key differences to help you determine which is best for you.
Key takeaways:
- Condensing boilers have an energy efficiency of 90% and are more eco-friendly.
- Non-condensing boilers are no longer legal in the UK but can be installed when special exemptions apply.
- Non-condensing boilers have an efficiency of 78% and lower upfront costs but are more expensive to run in the long term.
Condensing Boiler Vs Non-Condensing Boiler – Which Is Better?
The consensus is condensing boilers are better than non-condensing. This is mainly due to their higher efficiency and carbon emissions.
Let’s take a deeper look into both of the systems and what each has to offer.
Condensing boiler
What are condensing boilers? Condensing boilers are extremely energy efficient, lightweight and can be wall mounted. They are also suitable for any home or business, depending on the boiler size.
The thing that sets condensing boilers apart is their secondary heat exchangers. This is how they work:
- The heat from the burner is sent to the primary heat exchanger.
- Hot air then travels through this heat exchanger, where it remains until the temperature increases.
- This heat is then transferred to radiators.
- Exhaust gases are then transferred to the secondary heat exchanger.
- More heat is extracted during this process, and the water vapour in the exhaust gas condenses into liquid.
- This heat is then used to preheat the returning radiator water.
- The water vapour from flue gases is condensed into acid water. This liquid is safely expelled via a condensate pipe.
What are the advantages and disadvantages of a condensing boiler?
While their efficiency is the most distinguishing feature, condensing boilers have many advantages. However, as with anything, they also have a few disadvantages.
[table in Google Doc]
Popular condensing boiler brands
- Vaillant ecoTEC plus Combination Store gas condensing boiler
- Worcester Bosch Greenstar 4000
- Ideal Logic+ 30
- Viessmann Vitodens 050-W Gas Condensing Boiler
- Alpha Combi E-TEC Plus
Check out the Best Condensing Boilers of 2024.
Non-condensing boiler
Non-condensing boilers require a fuel source (usually gas or oil) to heat water. This water is then used to supply your home with heat. Boilers of this kind require a chimney for venting. They are also much heavier than condensing boilers.
As of 2005, non-condensing boilers are no longer legally allowed to be installed due to energy efficiency regulations. However, certain circumstances may allow for an exemption to this rule.
You may be allowed to install a non-condensing boiler if:
- Your property is a listed building, an older home or in a conservation area.
- There is no appropriate place for flue installation, or the flue extension requires significant structural alterations.
- It is impossible to install a proper drainage system for condensing boilers. This could include the likelihood of pipes becoming blocked or freezing.
- If the cost of installing a condensing boiler is notably higher than having a non-condensing boiler installed.
Grounds for these exemptions can only be determined after a certified installer has assessed the property.
What are the advantages and disadvantages of a non-condensing boiler?
At a glance, you may think that condensing boilers win hands down. But non-condensing boilers do have their merits. This is worth noting if your house or business is suited to installing a condensing boiler.
| Pros | Cons |
|---|---|
| Lower upfront costs | Lower efficiency (78%) |
| No standing charge | Higher fuel consumption |
| Fewer components, meaning less maintenance and easy repairs | Higher energy bills |
| No condensate pipe means no related issues | Higher carbon emissions |
| At risk of becoming obsolete due to energy efficiency regulations | |
| No secondary heat exchanger means wasted energy |
Popular non-condensing boiler brands
The only non-condensing boilers available in the UK are oil boilers manufactured by Mistral.
What Are The Costs Of Condensing And Non-Condensing Boilers?
The average cost of installing a condensing boiler is between £1,500 and £3,000, including installation.
The average cost of installing a non-condensing boiler (Mistral) is between £1,000 and £2,500 including installation.
Below is a breakdown of the costs for both condensing and non-condensing boilers.
Cost breakdown
Condensing boiler:
| Factor | Price Range |
|---|---|
| Boiler Unit | £500 – £1,700 |
| Boiler Installation | £600 – £1,000 |
| Average Running Cost | £500 – £1,500 (per year) |
| Average Standing Charge | £0.25 – £0.40 (per day) |
| Average Annual Maintenance | £100 – £120 |
Non-condensing boiler:
| Factor | Price Range |
|---|---|
| Boiler Unit | £1,000 – £4,000 |
| Boiler Installation | £200 – £500 |
| Average Running Cost | £1,200 – £1,500 |
| Average Standing Charge | No charge, not connected to the gas grid |
| Average Annual Maintenance | £110 – £150 |
As you can see, condensing boilers are the more cost-effective option despite their higher upfront costs. Non-condensing boilers have a higher running cost and a lower efficiency. Apart from the above costs, several factors further affect the prices of boilers.
As you can see, condensing boilers are the more cost-effective option despite their higher upfront costs. Non-condensing boilers have a higher running cost and lower efficiency. Apart from the above costs, several factors further affect the prices of boilers.
What factors affect the costs of condensing and non-condensing boilers?
Factors such as the type, installation, fuel source, standing charge, and maintenance have a large influence on boiler costs.
Type of boiler, model and size
The type, model and size boiler system you install will depend on your heating requirements and property size. There are three types of boilers for both condensing and non-condensing boilers:
- Heat only
- System boiler
- Combi boiler
System boilers are more expensive for condensing models as they require a hot water cylinder and more complex installation. Combi boilers are more cost-effective as they have a simpler design and installation process.
For non-condensing boilers, heat-only boilers are the most expensive due to the additional components and intricate installation. A non-condensing combi boiler is the more cost-effective option.
Installation
The installation costs will depend on several factors, such as
- Property size
- Property Location
- Installer’s prices
- Complexity of installation
- Removal of old or existing boiler systems
- Relocation of the boiler
Certain boiler installations may require additional water storage, condensate pipes, flues, and drainage systems. Besides this, a Gas Safe registered or heating engineer must be used.
Luckily, Eco Happy can help with the installation process. We’ll provide a quote in your area for condensing and non-condensing boilers for your home and business.
Fuel source
Your boiler’s upfront costs are further affected by the fuel source. Boilers using biomass and oil as fuel have higher costs, while natural gas and LPG are more affordable. Electric boilers have the lowest upfront costs.
The cost difference is due to the various complexities of the internal systems and the technology required to deal with each fuel source.
Standing charge
Daily standing charges remain constant and are a key consideration for the running costs of your boiler. This could add up to £110 – £182 per year. While oil boilers may not have a standing charge, other factors such as service or delivery fees will impact the overall running cost.
Maintenance
Annual maintenance is legally required for all boiler systems. This is over and above any repairs that may occur. Maintenance and servicing for non-condensing boilers is slightly cheaper than condensing boilers. Servicing costs are further influenced by your location and boiler accessibility. You might want to consider a boiler cover plan that includes annual servicing as well as any other unexpected repairs.
Which Boiler Is Best For Your Needs?
So, when it comes to condensing boilers vs non-condensing boilers, which one is best suited to your own needs?
Unless you meet specific criteria, you cannot install a non-condensing boiler on your property. But, even if you do meet the requirements, you may still be considering switching to a condensing boiler. Let’s have a look at the factors that will determine the best boiler for your needs.
Price
Boiler cost considerations include fuel source, unit, running, maintenance and installation costs. Those looking for an energy-efficient boiler that is also cost-effective should consider condensing combi boilers. This applies to both condensing and non-condensing models.
The most cost-effective fuel source is gas. Despite them being the most expensive to run, electric boilers have the lowest carbon emissions.
Installation
Non-condensing boilers have a higher upfront cost, which includes installation. They are limited in their placement and generally more cumbersome. If you have the option to switch to a condensing system, this would save money on installation. However, condensing boilers contain more parts and may require additional structural alterations.
Property size
The size of your property and central heating system will determine which boiler is best for your needs. Both systems provide adequate heat to homes but condensing boilers go a step further and ensure that no energy for heat is wasted. If you’re unsure about the size boiler you would need to meet your needs, you can try our Boiler Size Calculator.
Features
Between the two, condensing boilers are far superior when it comes to features. Apart from the mechanical features, such as:
- Secondary heat exchanger
- Condensing technology
- Lower flue gas temperatures
- Flue gas heat recovery
- Sealed combustion chamber
Condensing boilers can also be integrated with smart technology:
- Smart thermostats
- Energy monitoring
- Remote monitoring
- Diagnostics
- Weather compensation
- App control
- Zoning systems
Most non-condensing boilers do not have the capacity for such technology. If you want the convenience of these features, a condensing boiler is the one for you.
Energy efficiency
Condensing boilers are hands down the more energy-efficient boilers. They are also the more eco-friendly option compared to traditional oil boilers.
Safety
Condensing boilers are the safer option compared to non-condensing boilers.
Since the only non-condensing boilers available in the UK are oil boilers, owners should be aware of potential risks, such as:
- Carbon monoxide leaks
- Oil leaks
- Overheating
With the correct boiler maintenance, this potential hazard can be avoided.
Maintenance
The maintenance costs for a condensing boiler may be only slightly more than a non-condensing boiler. But remember, condensing boilers have more components. Apart from annual servicing, other repairs may be required at any given time for one or more of these components. Follow these 8 boiler maintenance tips to ensure your system stays in top condition.
Get A Quote For Condensing Or Non-Condensing Boilers Today
Visit Eco Happy today and get a free quote for boiler installation. Our expert team can answer any questions about condensing and non-condensing boilers for your home or business.
FAQs
How would I replace a non-condensing boiler with a condensing boiler?
If you have decided to get a new boiler, follow these steps:
- Contact a Gas Safe registered or heating engineer to assess your property and get an installation quote.
- Research any available government grants for your new boiler.
- Prepare for any alterations or modifications.
The installation will usually take up to two days.
Are there any government grants for switching to a condensing boiler?
Yes, there are a few government grants and incentives available to those wanting to make the switch, including:
How do I tell If I have a condensing boiler?
If you’ve moved into a new home, you may ask yourself “How Do I Know If My Boiler Is Condesning?”. You need to check for a flue pipe, condensate pipe and the efficiency rating. If you have the model number or serial number you could also do a quick online search.
Our Verdict
If you have the choice, switching to a condensing boiler is the more viable option. You will lower your carbon footprint, have better energy efficiency, and save on long-term costs. Those with non-condensing boilers can enjoy a few benefits but should prepare for government regulations to clamp down even further on these models. You should also be aware of the higher long-term running costs of non-condensing boilers and their lower efficiency. If you want to switch to a condensing boiler, contact us at Eco Happy for a free quote.
James Elston
Boiler Expert
James Elston is the top boiler replacement and heating expert at Eco Happy. He has over 20 years of experience in the industry, focusing on Gas Safe boiler installations and offering home-heating and energy-saving solutions to homeowners across the UK. From sourcing the most energy-efficient combi boiler to providing specialist heating advice, James ensures that Eco Happy maintains the highest standards and best customer service.