Boiler Guide

At the Cheltenham boiler company, we offer a wide range of services, from servicing to repair and replacement to complete boiler installations in Cheltenham. For a full list of services please go to our Services page.

Choosing a new boiler can be a daunting task for most people, understanding heating systems can be pretty complex and that’s where we can help.

With our boiler guide, selecting a new boiler need not be an intimidating prospect. Take a look at some frequently asked question here.

Use our boiler guide to learn which system you currently have, and if you would like a direct replacement or to replace and customhouse a system that’s more suited to your needs.


Combination boilers , or more commonly referred to as a Combi boiler, are the UK’s most popular boiler.

They are a compact unit, acting as both an instantaneous water heater and central heating boiler.

Rather that storing and heating water, combination boilers will function as a single stand alone unit removing the need for tanks and cylinders.

Combination boilers are ideal for small to medium homes for people with 1 bathroom and an en-suite who do not need a lot of hot water at the same time.



With no water tank to heat up, combi boilers can provide an unlimited supply of hot water on demand. No waiting time!


Combi boilers are far less complex than traditional heating systems, which means that installations tend to be cheaper. It is also easier to find replacement parts if a problem occurs.

More Compact

As there is no need for a separate water tank, combi boiler systems take up much less space than conventional heating systems.

This makes them ideal for homes that have limited room.


Limited Use

With a combi boiler it is not possible to run more than one shower or bath at a time, or to turn on the hot tap while showering.

This may be an issue if you live in a large house with a number of bathrooms and en suites, or with lots of people.

No Immersion Heater

As there is no water tank, if your combi boiler breaks down then you will be left without hot water as well as central heating (unless you install an electric shower).



Conventional boilers, often known as heat only or regular boilers, are popular for larger households as they can heat your home and water efficiently.

Conventional boilers use a storage cistern with two feeds.

There is one feed for hot water and one for cold, and the water is pumped through the system to either be heated up or stored as hot water to be used when it is needed.

You might want to choose a conventional boiler if you have lots of people in your family and you have more than one bathroom.

This is because they can cope with delivering water to two or more outlets whereas a combi boiler will struggle to do this.



  • They still work well even if your mains pressure is low
  • You’ll still get hot water even if someone is running the shower and the kitchen taps at the same time
  • They’re easy to maintain as they have a simple design
  • You can install an immersion heater to the hot water cylinder to use if the boiler breaks down
  • Conventional boilers are compatible with older central heating system


  • Pressure flow for showers and hot water can be low
  • You’ll need space for the hot and cold feed tanks
  • Conventional boilers aren’t as efficient as combi boilers – there will be heat loss as hot water is stored
  • Your hot water can run out and take time to reheat
  • Hot water isn’t supplied on demand – you need to heat it in advance


System boilers are very similar to a conventional boiler as both require an open vented hot water cylinder or an un-vented cylinder.

The system boilers have all the major components built into the boiler itself.

Using an expansion vessel built within the boiler, it removes the need to have a tank in the loft and if used in partnership with an un-vented cylinder.

These boilers completely remove the need for any tanks in the loft at all whilst also giving you the capability to have hot water delivered at mains pressure.

System boilers would be an ideal set up in homes where water usage is higher, multiple bathrooms and hot water outlets.


The system boiler is ideal for homes where there is more than one bathroom.

System boilers can supply hot water to many outlets at the same time without fluctuation.

No need for tanks in the loft, freeing up space and eliminates risk of freezing, leaks and contamination.


Will need room for the cylinder.

The hot water can run out and will take time to reheat.

Find below an example of a system boiler with an open vented hot water cylinder.

Below find an example of a system boiler used with an un-vented cylinder.


Back boilers are attached to the rear of a fire place or stove. This type of boiler grew in popularity through out the 60’s, 70’s and 80’s.

With the introduction of the condensing boiler they have been predominantly replaced by more efficient models.  A drawback of a back boiler is the lack of energy efficiency.  

This type of boiler was once considered normal, but are now quite old fashioned and becoming obsolete.

Regulations now state that back boilers should be replaced with modern energy efficient boilers.

Boiler Servicing

Here at The Cheltenham Boiler Company we cover boiler installations in Cheltenham and surrounding areas.

We specialise in energy efficient heating systems, so if your boiler is costing you too much because it’s too old then it might be a good time to consider changing your boiler to save you money on high-energy bills.

Our specialised team are qualified and have great experience in boiler installations.

Full Boiler Servicing

The Cheltenham Boiler Company are happy to help you with all of your central heating needs. We specialise in boiler installations, replacements and boiler repairs.

Boilers require servicing a minimum of once a year which ensures safety and efficiency.

Installing a brand new boiler is an important job that needs to be done right first time, and there are many factors to consider.

Our service is second to none, we cover everything from providing you with a free non-obligation quote, right the way through to registering your new boiler and finally commissioning the finished system.

Health and Safety is an important factor within our everyday workplace, we strive to work in line with all legislative requirements.