Combi Boiler - Everything You Need to Know
Factory Heaters • Jul 01, 2021

There are three types of boilers which all operate in different ways, namely:

 

1.    Combi boilers

2.    System boilers

3.    Regular boilers (Heat only)

COMBI BOILERS

What is a Combi Boiler?


Combi boilers, or combination boilers, are considered to be the United Kingdom’s most popular type of boiler.


Usually installed as a single wall-hung appliance, commercial combi boilers are very compact and highly efficient, not only supplying all the heating requirements, but also hot water for sanitary use, such as bathing or showering, washing up, food preparation, hand washing etc,  


They ensure not only significant savings on installation costs, but also guarantee lower running costs too, making them the best choice for larger domestic properties or commercial applications, where both heating and hot water are required. 


Unlike traditional systems, the combi will instantaneously heat water when turning on the hot tap, so there is no need for a hot water storage cylinder, making this product the ideal choice for properties with limited space. 


  • Atag combi boiler

    Slide title

    Write your caption here
    Button

How a Combi Boiler Operates.


A combi boiler integrates a central heating boiler and a water heater, heating water via an integral heat exchanger directly from the cold mains. The boiler fires up if the room thermostat gives a signal to do so when the temperature falls below a set point, allowing heat to be injected into the central heating system. Additionally, the boiler may 'modulate' or turn itself down once you reach the thermostat set point, maintaining the heating at the proper temperature, which saves energy.


When a hot water tap is switched on, a valve inside the combi boiler redirects the heat into the hot water supply, producing hot water until you turn the tap off, at which point the valve resets to the ‘central heating' position. Heat may be delivered to either the hot water taps or central heating system, but never both simultaneously.

 

Due to the much higher efficiencies, it is now a legal requirement to have a condensing boiler instead of a non-condensing boiler when replacing a boiler or fitting a new one for the first time.


A non-condensing boiler only has one heat exchanger, so the waste gases that exit the boiler flue could reach up to 250°C. This is wasted heat that could be recycled and used in the system to reach maximum efficiency. A condensing gas boiler is able to recycle this heat from the waste gases and use it to heat the water.

A combi boiler, unlike an open vent boiler, operates on a closed system. Any air that gets into the stream has an impact on the heating, boiler, and pump. If the boiler loses any more pressure, it shuts down and displays an error code. A loose or rusted connection might result in a sudden loss of pressure.

 

To restore a combi boiler's pressure to the appropriate levels, one uses a filling loop. A pressure gauge is normally located next to the display on each boiler. The combination boiler's pressure should never be permitted to dip below 1 bar or rise above 3 bar. The safest range is between 11/2 and 2 bar.


How Do You Fuel a Combi Boiler?


As most UK Commercial properties are linked to mains gas via an underground network, gas is often used to fuel a gas combi boiler. However, this is not the only available method. Combi systems can also be powered by LPG, oil, or electricity. LPG is normally delivered in bottles that must be replenished on a regular basis. Similarly, you normally store oil in a tank that must be replaced on a regular basis.


The future of Combi Boilers


In an effort to reduce our greenhouse gas emissions by 80% by 2050, the UK government is seeking to change the way in which we heat our homes. According to recent figures, heating constitutes around 40% of the UK’s energy consumption. The introduction of fuel sources such as hydrogen could help us reduce our carbon emissions.             

 

Hydrogen would be used as an alternative to Natural Gas, LPG and oil, which all produce carbon dioxide as a by-product of the combustion that takes place. There have been many suggestions as to how hydrogen can be produced as a fuel source, including an electrochemical process where hydrogen is separated from the source fuel. In this case, the carbon emissions would have to be captured and permanently contained.

Should You Purchase a Combi Boiler for your Commercial Application?


A combi boiler needs enough mains water pressure to give a reasonable water flow rate; if the mains water pressure is too low, hot water only trickles out the tap. System boilers may be a better alternative for you if your mains water pressure is low or if your Commercial premises have more than one washroom facility.

 

It is also crucial to make sure the boiler's heat output is adequate for your requirements.

Combi boilers produce two types of heat: one for domestic hot water and another for central heating. Producing hot water requires more effort and thus more heat than heating radiators; as a result, the hot water output is generally what defines your boiler option. A Gas Safe Registered installer can assist you in determining what boiler you need to meet all your Commercial heating & hot water needs.

What are the advantages of a Combi Boiler?

Combi boilers offer the following benefits:


  • They are easy to use – The majority of combi boilers contain simple controls. You can program the system's heating to turn on when you need it due to the temperature and time controls. The ability to choose your desired temperature, at any given time, enhances the comfort of your premises, which reduces your fuel bills and gives you more control.


  • The boiler itself contains everything needed to supply heat to the radiators or hot water to the taps, eliminating the need for a central heating pump or hot water storage cylinder - ideal for commercial premises with limited space.


  • As a combi boiler does not require a water tank or a hot water storage cylinder, it requires less plumbing, which saves time and money during the installation process.


  • Lower maintenance costs - the integral heating and hot water functions are covered by the boiler manufacturer's warranty/guarantee.


  • No long wait times for hot water


Combi Boiler

What are the disadvantages of a Combi Boiler?

Combi Boiler
  • They do not work well in properties with poor flow rates and/or poor incoming water pressure.


  • Hot water flow rates are reduced when providing hot water to two or more outlets simultaneously, although this is really only a problem in properties with two or more washrooms.


  • A combi boiler system does not have backup immersion heaters to heat any hot water in the case of a breakdown.

Other common questions about Combi Boilers

Condensing boiler vs combi


When it comes to gas combi boilers, two of the most popular types are condensing and combi boilers. Condensing boilers are the most efficient type of boiler available, as they use a secondary heat exchanger to extract more heat from the fuel source. This means that they can reach up to 90% efficiency, making them an ideal choice for those looking to save money on their energy bills. Combi boilers, on the other hand, are a combination of a water heater and central heating system in one unit. They provide instant hot water on demand and are also highly efficient, reaching up to 95% efficiency. Both types of boiler offer great value for money and can be used in both domestic and commercial applications.

What is the optimum temperature to set a combi boiler?


The combi boiler has a control panel on it which allows you to set the temperature of water that will circulate around your home's heating system and come out as hot or boiling! Combination boilers often give the best results when heated to 75°C for central heating and 60 °C domestic hot water. Lowering this temperature will help reduce any risks of scalding, so it's important not only in your home but also at businesses where employees may use extremely high temperatures on certain tasks like cooking or taking care procedures!

Are there any combi boilers to avoid?


Combi boilers are an efficient and cost-effective way to heat your home, but there are certain situations where they may not be the best option. If you have a large family or live in a multi-story house, then a combi boiler may not be able to provide enough hot water for everyone. Additionally, if you have low water pressure or an old system, then a combi boiler may not be suitable as it requires a high level of water pressure to operate efficiently. If you're unsure whether a combi boiler is right for your home, it's best to consult with an experienced professional who can assess your needs and recommend the best solution for your situation.

Facts and Tips for Choosing the Best Residential Boiler


When it comes to residential heating systems, one of the most popular choices among homeowners is a Combi boiler. But what is a Combi boiler and why do many people opt for it over a traditional system or hot water cylinder? Combi boilers are relatively new, with the first models being introduced in the UK back in the early 70s. Since then, they have become increasingly popular due to their energy-saving potentials, lower running costs, and space-saving designs. With a Combi boiler, you get both heating and hot water supplied by the same unit, which eliminates the need for a separate hot water cylinder or cold water supply tank.


One of the most well-known brands of Combi boilers is Baxi combi boiler, which offers an extensive range of energy-efficient and reliable models to suit every household's needs and budget. But before investing in a new Combi boiler, it is essential to know how it works and what boiler do i need for my house. Typically, a Combi boiler is controlled similarly to a traditional system, with the added benefit of being able to adjust the heating and hot water controls separately. Combi boiler how it works is by heating cold water directly from the mains via a heat exchanger, which eliminates the need for a hot water tank or cylinder.


Although there are many benefits to a Combi boiler, it may not be the best option for those with a larger property or high hot water demand, as it may struggle to meet the demand, and a conventional or system boiler may be more suitable. However, if you're looking for a space-saving, energy-efficient, and cost-effective solution for your heating and hot water needs, a Combi boiler may just be what you need.

OUR COMBI BOILERS FOR SALE.


If you would like further advice regarding your hot water requirements, please do not hesitate to contact us directly either by


EMAIL CALL

Share.

Comment.

Shop Our Industrial Heating Solutions

FULL STORE

Latest.

energy-efficient fan coil water heater
By Factory Heaters 16 May, 2024
Upgrade to energy-efficient fan coil water heaters. Perfectly designed for UK businesses. Explore our range now!
A thermostat displays the temperature at 18 degrees celsius
By Factory Heaters 15 May, 2024
Optimise your commercial gas warm air systems with our control and comfort accessories. Enhance efficiency and comfort today!
Warm School Hall
By Factory Heaters 08 May, 2024
Upgrading your UK office or school with a commercial combi boiler is a savvy investment. These boilers offer a space-saving, efficient solution for both heating and hot water, eliminating the need for separate tanks. With models like RINNAI ZEN and ATAG , you'll find options tailored to larger buildings, featuring durable stainless steel heat exchangers and capable of delivering high-temperature heat efficiently. Whether you're looking to cut operational costs or enhance comfort, installation flexibility ensures these systems fit your specific needs. Opting for a commercial combi boiler not only modernises your facilities but also prepares your business for future demands with reliable performance. Discovering more will unveil the potential benefits further. Combi Boiler Basics Before diving into the specifics, it's crucial to understand that a combi boiler is a highly efficient, space-saving solution that provides both heating and hot water from a single unit, eliminating the need for separate water tanks or cylinders. When you're considering a combi boiler, you're looking at a system that can handle both high-temperature instantaneous hot water, perfect for kitchen facilities , and low-temperature instantaneous hot water, ideal for wash hand basins. This versatility ensures that your business can meet a wide range of needs without the complexity and space requirements of multiple systems. Combi boiler basics also highlight the flexibility of installation , with models suitable for both indoor and outdoor setups. This ensures that, regardless of your premises' layout or space limitations, there's a combi boiler solution that fits. Furthermore, the efficiency of these boilers means that they can deliver high temperature heat (60-70 degrees), crucial for maintaining comfort in offices and schools . RINNAI ZEN Models Overview Let's dive into the RINNAI ZEN models, offering a versatile and efficient solution for your heating and hot water needs. Whether you're considering an upgrade for your office or school, the RINNAI ZEN indoor-outdoor combination boilers come in various kW options to suit your specific requirements. These models, including the RINNAI ZEN-24 , ZEN-29, and ZEN-35, are designed to deliver high temperature (60 degrees) instantaneous hot water, perfect for kitchen facilities that need consistent, high-efficiency performance. Additionally, these boilers are capable of delivering low temperature (32 degrees) instantaneous hot water for wash hand basins, ensuring a versatile solution for all your hot water needs. What sets the RINAI ZEN series apart is the stainless steel heat exchanger, guaranteeing consistent high efficiency over time. This, alongside the year boiler warranty including parts and labour, ensures your investment is protected. Whether installed indoors or outdoors, the RINNAI ZEN range is built to meet the rigorous demands of commercial environments, offering a reliable, high-performance heating and hot water solution. With these models, you're not just upgrading your system; you're investing in a future-proof solution for your facility. ATAG Combi Options Turning our focus to the ATAG Combi Options, you'll discover a range of powerful boilers tailored to meet the higher demand of larger buildings. These ATAG combi boilers come in varying kW ratings, ensuring that regardless of your facility's size, there's a model that fits your needs perfectly. The key to their efficiency lies in their design, which includes a stainless steel heat exchanger known for its durability and effectiveness in transferring heat. What sets ATAG apart isn't just their robust performance in delivering high temperature heat—up to 70 degrees—but also their low energy consumption. This makes them an ideal choice for businesses looking to reduce their carbon footprint without sacrificing comfort. Each boiler is designed with an integral cylinder, streamlining the system and saving precious space within your utility areas. Moreover, the combination of high efficiency, a stainless steel heat exchanger, and the capability of delivering high-temperature heat efficiently makes ATAG combi boilers a top choice for UK offices and schools. They offer a reliable solution for heating and hot water needs, ensuring a comfortable environment for everyone, all while keeping operational costs in check. Installation Flexibility Having explored the robust performance and efficiency of ATAG combi boilers, it's important to consider how their installation flexibility can further benefit UK offices and schools. The qcr ATAG combi boiler kW range, from the compact 25kW model to the more powerful 51kW option, provides a versatile solution that can meet varying demands for high temperature heat. This adaptability is enhanced by the Rinnai Zen LPG modular solution, which offers an alternative for locations where natural gas isn't available. Moreover, the ability to choose between indoor and outdoor installation adds another layer of flexibility. Whether it's the space-saving requirements of a small office or the expansive layout of a school, these combi boilers can be adapted to fit the space available. The ATAG boiler manual provides clear instructions for both scenarios, ensuring a smooth and efficient installation process. Additionally, OpenTherm connection options extend the flexibility to include integration with existing heating controls, further optimising energy efficiency and comfort. This level of adaptability makes the ATAG and Rinnai Zen combi boilers an excellent choice for any UK office or school looking to upgrade their heating system with minimal disruption and maximum efficiency. Instantaneous Water Heating Instantaneous water heating ensures you get hot water when you need it, without the wait or waste. The QCR combi boiler is a prime example of efficiency, offering outputs of - W, and is designed with an integral cylinder to satisfy immediate high domestic hot water demand. This means you're not left waiting for hot water, whether you're washing hands or needing it for kitchen facilities in your office or school. It's tailored to provide exactly what you need, when you need it. Moreover, the QCR combi boiler is equipped with a stainless steel heat exchanger, ensuring consistent high efficiency over the entire lifetime of the boiler. This isn't just good for your water heating; it's also beneficial for your wallet in the long run due to the efficiency savings. Plus, with the possibility to control up to heating circuits with -way mixing valves, it allows for precise temperature control per circuit room. This feature is incredibly useful for buildings with varying hot water needs in different areas, ensuring comfort and efficiency across the board. High-Temperature Heat Delivery Understanding the efficiency of instantaneous water heating leads us naturally to explore high temperature heat delivery in commercial settings. For your UK office or school, delivering high temperature heat, especially in the range of 60-70 degrees Celsius, is crucial for several applications. This includes providing hot water for kitchen facilities, where regulations often require temperatures to be at least 60 degrees to ensure hygiene and safety. When considering a commercial combi boiler, you're looking at units capable of meeting these demands efficiently. For instance, models like the RINNAI ZEN-24 , ZEN-29 , and ZEN-35 , along with the ATAG Q series, offer varying outputs from 24kW to 51kW. These boilers are designed for both indoor and outdoor installation, providing flexibility in integrating high temperature heat delivery systems into your existing infrastructure. It's essential to select a boiler that not only fits your immediate needs but also anticipates future demand. The right boiler ensures you're not just compliant with current regulations but are also prepared for any updates in health and safety standards. Investing in a high-quality combi boiler means delivering consistent, high-temperature hot water efficiently, ensuring your facility remains operational, safe, and comfortable for all users. LPG Modular Solution In today's market, the RINNAI ZEN 24 LPG Modular Solution offers a flexible and efficient option for those requiring LPG fuelled heating and hot water systems in commercial settings. Priced at £1,500.00, this model stands out for its adaptability, able to be installed both indoors and outdoors, catering to the unique needs of UK offices and schools. You'll find it delivers high-temperature (60 degrees) instantaneous hot water, perfect for kitchen facilities, and low-temperature (32 degrees) water for wash hand basins, ensuring it meets a range of demands. Moreover, it's capable of providing high-temperature heat between 60-70 degrees, making it a versatile choice for various applications. The RINNAI ZEN 24 LPG Modular Solution isn't just about its functionality. Its design for LPG fuel use makes it an ideal choice for locations where natural gas isn't available, offering an efficient alternative that doesn't compromise on performance. Whether you're looking to upgrade your existing system or implementing a new one, this solution is designed to meet the high demands of commercial environments efficiently, making it a smart investment for the future of your business.
Share by: