If you’re looking for a new combi boiler but don’t know which one to choose, you may feel unsure where to start. That’s why we created our easy to use Boiler Selector Tool. This simple series of questions breaks down this process into small steps and takes the guesswork out of finding your new boiler.

Simply work your way through the questions and select “combi boiler” when you reach the “What type of boiler do you require?” question. But what do all these options mean, how do they influence your choice of model and exactly what is the best combi boiler for your home? 

Here we take a look at all the factors that determine the best combi boiler for you.

Checklist

Before you opt for a combi boiler, make sure you satisfy the following factors:

  1. You live in an area with normal or high water pressure
  2. You don’t often need to use several hot water appliances (sink, bath, shower) simultaneously
  3. The boiler is going to be relatively close to the furthest bath, shower or sink (less than 20 metres)

You can read more about combi boilers, including their pros and cons, in this article.

Property type

Options

First, you’re asked to decide between a detached house, semi-detached house, terraced house, bungalow and flat. 

Why we ask

The smaller the property, the less powerful your boiler needs to be, and vice versa. This is important because although the boiler uses mains pressure to deliver hot water, you may still notice a drop-off in pressure if your boiler is too small for the home. Also, the longer the pipework between the boiler and the tap, the longer you’ll have to wait for the hot water to emerge when you turn it on.

How many bedrooms do you have?

Options

We now ask how many bedrooms you have: 1, 2, 3, or 4 or more.

Why we ask

This will give us two indications: what will be the demand placed on the central heating system, and roughly how many people live in the home. Both of these factors feed into the calculation, as they determine the power and size your boiler will need to be. For example, if you have a large family, it’s more likely there will be simultaneous hot water demands, meaning the best new boilers for your home will be different from those for a smaller property.

How many bathtubs do you have?

Options

We ask whether you have 1, 2 or 3 or more baths.

Why we ask

Although most households have just one bath (usually with showers in addition), if you’ve got two, you need to know that you can use them at the same time. Two baths running simultaneously would be asking a lot, even of the best small combi boiler — a larger model would also struggle. In this case, it’s possible that the best fit may be a system boiler or conventional heat only boiler.

Alternatively, if your home happens to have two baths, but you hardly ever use them, or would never use both at the same time, select “1 bath”.

How many showers do you have?

Options

How many self-contained showers do you have: 1, 2, or 3 or more. If you have a shower that runs directly from your bath-tap mixer, discount it for the purposes of this question. Additionally, if you have an electric shower, ignore it – as it doesn’t run on gas, it has nothing to do with finding the best central heating boiler for your property. 

Why we ask

We need to know how many self-contained shower units you have that run from the boiler. Like baths, if you have several running simultaneously, it will put a demand on the boiler, and you could find the water comes out at lower pressure and temperature than you would like.

Again, if you have a house with several shower units but only ever use one at a time, select 1.

What type of boiler do you require?

Options

Here, you’re asked if you’d like a system, heat only or combi unit boiler.

Why we ask

The different types of boiler all come with their pros and cons. The main pros of the combi model is that they provide instant hot water and they don’t heat water unnecessarily, only heating the water that’s used. This means a combi boiler doesn’t require separate storage for water, making their compact size ideal for smaller properties.

Larger households with multiple occupants would often be best served by a system or heat only boiler setup, as they can deliver hot water to multiple taps at the same time.

However, for the purpose of this article, we’ve assumed you’ve opted for the combi boiler.

What kind of fuel does your boiler use?

Options

There are two options: Natural gas and LPG (bottled gas).

Why we ask

The majority of households in the UK use natural gas, i.e. mains gas. However, some isolated buildings are not connected to the gas network, and will therefore require gas to be delivered in LPG (liquid petroleum gas) bottles. This fact might influence the type of gas boiler you can use.

We'd suggest the following boilers for you

Options

You’ll now be given various options based on the facts and figures you’ve given us.

Why we ask

These are the combi boilers that will cope best, considering the information you’ve provided. Although you’ll be given some basic information at this stage (the duration of the warranty, its efficiency rating and what the unit looks like), we’d urge you to look deeper into the specifications before you make your choice. 

Ideally, this guide will give you a ball-park idea of the kind of boiler you’ll need and how much it will cost, but you should ask a professional installer to confirm your choice, as they’ll know if you’ve chosen the most appropriate and best rated combi boiler unit for your needs.

Controls and Accessories

Options

Finally, you’ll be offered a range of controls and accessories. These options will depend on the boiler you’ve chosen, but typically they’ll let you choose between different types of timer, manual connection thermostat and mobile-connected devices. You can select more than one accessory here.

Why we ask

The control is a crucial part of your central heating system, and will instruct the boiler to fire up to get your home warm. At its simplest, it’s just a thermostat that detects room temperature and turns on and off if it’s colder or hotter than your chosen setting.

Modern systems are connected to the internet via your Wi-Fi, and you can turn the heating on and off wherever you are – handy if you’re about to set off for home from work on a wintry day, but don’t want the heating to be on all day long.

Ultimately, it’s your choice. The simpler solutions cost less, but the modern ones give you more flexibility to help you keep your home at the ideal temperature.

Please get in touch if you need help

If you have further questions about finding the best central heating boiler for your home, please get in touch – we’ll be glad to help.

For more support, read about a range of central heating and boiler-related topics on our Tips and Advice page, or bookmark the Ideal blog for the latest news.

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