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Combi Boiler vs Conventional Boiler


Lee Devlin

Published on: 04/04/2022
Combi Boiler vs Conventional Boiler - Homecure Plumbers London

Combi or conventional… what’s the difference? As busy London plumbers, we’ve heard the question before! And we’re aware that the word “Boiler” can often strike fear and dread for homeowners and tenants, especially if your old boiler breaks and you need emergency boiler repairs. It would be an understatement to say that our boilers play a pivotal part in running our homes. So, when it is time to replace our boiler, deciding which type can be quite complex. For instance, will it be more cost-effective to install and combi boiler? Or should you stick with your conventional boiler because if it’s still fully functional, why do you need to replace it?

At Homecure, we don’t just try to help our customers with boiler issues. We also like to educate our visitors with helpful guides and tips to help you get the most out of your existing boiler. Sometimes, it can be more sensible to replace your old boiler. Although it might be costly at first, you will save money with your gas and energy prices, which makes it more affordable going forward. So, we have created this blog to help you decide if a combi boiler is better than a conventional one.

Oh, and to make it a little easier, we have tried to help you identify which boiler is right for you and your home by discussing the different functionalities. We have tried to include as much information as possible for each boiler so that it can assist you in making the decision of either repairing, keeping your existing boiler, or choosing to install a combi or conventional boiler. First, we need to explain the difference between a combi and a conventional boiler.

Combi Boiler

In simple terms, a combi boiler or, in other words, a combination boiler can be described as a compacting heating device. A combi boiler can heat warm water on demand or constantly. Generally, a combi boiler has two distinct functions, it provides your home with hot water and central heating through one unit. So, the warm water supply comes directly through the main system, and the unit can heat the water on demand.

Rather than using a hot water cylinder or a cold-water supply tank, a combi boiler will provide hot water directly through the boiler. The combi boiler will automatically divert the hot water to the tap or the central heating system. One of the best parts of a combi boiler is that you will have more space as it’s all the main functions of a boiler are carried out through one system.

Moreover, a combination boiler functions and operates through valves in different directions. This boiler system means that the water will go directly to the taps or flow straight into the central heating system. It is worth keeping in mind that a combi boiler is not built to run both systems simultaneously. So, there might be times when your boiler drops in pressure. For example, if you have a shower at the same time as running the tap, you might notice a reduction in the flow of water pressure.

When we install a new combi boiler, we always try to explain to our customers that this type of boiler can only process one hot water request at a time. Thus, we would assert that a combi boiler is better as it is more cost-effective and modern than a conventional boiler, which we highlight in the next section.

Conventional Boilers

We have discussed what a combination boiler is and how it might be more appropriate for your home, depending on your energy usage. Generally, you will find a conventional boiler in older homes. Although, it is worth noting that some newly built homes still install conventional boilers, depending on the number of rooms. As mentioned, a combi boiler might struggle to process more than one hot water request at once.

For instance, if you have the hot water running downstairs, you might notice that the pressure drops, or cold water might flush through the tap at the same time as the shower. So, you might find that you have a conventional boiler if you have more than three rooms on your property. The reason conventional boilers are found in old buildings or larger homes is due to the additional space that is required for the two separate components.

A conventional boiler will come with two cold water tanks. You will normally find that one of the tanks is either in the loft or the airing cupboard. We normally recommend fitting a conventional boiler in the airing cupboard. It means it is easier to access if your boiler should develop a fault. Storage is key with these boilers, which is why a large property is advised if you opt for a conventional boiler.

A combination boiler heats water constantly or on-demand. In contrast, a conventional boiler heats several litres and then stores it within the hot water system/cylinder. Although a conventional boiler is more outdated than a combination boiler, it can be more effective in multiple bathrooms homes. You should also remember that you may have to wait up to thirty minutes or more for the water to heat inside the cylinder. So, it raises the question of which boiler is the best, a combi or a conventional boiler?

Which Boiler is Right for You?

We have reached the end of this article, so it’s time to decide which boiler is best for you and your home. Although we have provided you with the information, the decision is ultimately yours. We have highlighted that both boilers function differently. Moreover, the perfect boiler for your home comes down to your hot water usage, storage and the size of your home or commercial space.

Nowadays, most people opt for a combination boiler since you will have hot water constantly. The only downside to a combi boiler is that it cannot process more than one hot water request at a time. Generally, we find it is more cost-effective than waiting for the hot water tank to heat up. Some people who have a conventional boiler will keep the hot water turned on at all times, but this can end up being quite costly. Ultimately, there is no correct answer to which boiler is the best. As we have highlighted, it comes down to your household requirements and needs. Perhaps you are ready to upgrade from a conventional boiler to a combi boiler, but you have a large home. Then, why don’t you speak to Homecure, and we will visit your property and provide you with the best options and prices. Sometimes, we do not need to upgrade our boilers, especially if we schedule regular maintenance. We hope that we have helped you identify the difference between a combination and a conventional boiler.

Lee Devlin
Publication date: 04/04/2022

Lee Devlin is the managing director of Homecure Plumbers, London's favourite local plumbing service. Since 2009, Lee's been leading a large team of gas safe plumbing and heating engineers as well as growing a successful business built on quality customer service and workmanship, in a competitive industry within the Capital. He's been in the game for a long time, so he regularly shares his knowledge and experience with the public. His expert tips have been featured in lots of well known publications such as: The Sun, Metro, Insider, Homes And Gardens, Country Living and more!

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