There is a mass of information available online surrounding central heating systems, covering everything from the different types of heating concepts, type of boilers available on the market, confusing jargon on how they are installed etc. So, we’re going to keep things simple and focus on the three types of central heating systems commonly found in modern UK homes which are:

1) Combi Boiler Systems (sometimes we refer to this as a gravity fed systems).

2) Conventional Heating Systems.

3) Pressurised Central Heating Systems.

Why is it important to know what type of central heating system you have in your home? While the Maintracts team spend most of their time thinking and working with central heating systems, for most people, they only become interesting when there is a problem with the heating and hot water in their home. However, having a little knowledge about how your home and water is heated will be useful to you when the time comes to upgrade your heating system. Knowing the basics around what the different types of central heating systems can achieve, will help you match up the right one to the demands of your home, family or business. Heating systems have to be fitting to the building they are placed in, so there is no such thing as a one-sized-fits-all system. Some will be better suited to smaller buildings, while others might work more efficiently with a grander, more complex set up.

The first thing to clarify is that with about 2 million homes in the UK connected to the gas network, it is likely that the majority of our readers boast gas boilers rather than electric or oil operating ones. Secondly, there are many different types of central heating systems available, but most homes in the UK have a wet central heating system meaning that it uses hot water to heat the building (whereas an electric system would use electricity to generate heat for example). In a bid to help the majority of readers, we are going to focus on the three main wet central heating systems.

Combi boiler systems (contain combi boiler)

Nowadays, combi boilers are a great fit for most homes due to their compact size and ability to contain everything they need to heat a home within the boiler itself. No cylinder or water tanks in the loft are needed. Whenever hot water is needed, a combi boiler heats water directly from the mains and sends it straight to the tap. However, while their space-saving size hosts a heap of positives, it does mean that the amount of hot water they can provide is limited. Therefore, if your house has more than one or two bathrooms, this will probably not be the boiler for you.

Do I have a combi boiler? If you don’t have a hot water cylinder (located below a cold-water storage tank) then you have a combi boiler. Plus, you’ll likely hear your boiler fire into action every time you turn the hot water on – it’s a very distinctive sound.

To summarise the benefits:

  • Highly efficient as they only heat the water you need.
  • Water is run at mains pressure as it flows through the boiler cold and is then heated. This means water pressure throughout the home should be good.
  • No need for hot water tank. Ideal for small properties where space is limited.

Conventional heating systems (contain regular or conventional boilers)

Readers born in or before the nineties will probably remember these older style central heating systems by their need for a hot water unit, as well as a cold-water tank in the loft. They take up heaps of space and obviously require an actual loft space to house a tank and a loft or cupboard space on the highest floor (typically in a cupboard in the room directly below the tank in the loft).

Simply put, in a conventional system, cold water is controlled by mains pressure and stored in a cold-water tank in the loft. The boiler is used to heat this water which when warm, flows down to the lower floors via the radiators, into your radiators and out through the taps. All achieved by the natural pull of gravity (hence why this is sometimes referred to as a gravity fed water system).

Being reliant on gravity does mean that conventional systems are limited with regards to pressure capabilities and generally produce lower water pressure and flow. Plus, heating an entire hot water tank can be wasteful in terms of energy efficiency, as it may not all be used despite requiring heaps of energy to heat it up and keep it warm.

Where would a conventional heating system typically be used, I hear you ask? Well, they still have their uses. For example, we would generally replace an old regular boiler with a new one and we would also consider using one in locations where a building’s water pressure is low.

Do I have a regular or conventional boiler? If you have a large cold-water storage tank in your roof/loft and an old foam or jacket insulated copper hot water cylinder in your airing cupboard then it is likely that you have a gravity fed/conventional system.

Pressurised central heating system (contain a system boiler)

A pressurised system works in a similar wat to a combi system in that mains water is heated directly rather than in a hot water tank. The differentiator is that it is heated by a water cylinder rather than a hot water tank. The cylinder is a small piece of kit that you can be placed almost anywhere in your home and will heat water as it passes through. Basically, it means that hot water can be run at mains pressure from multiple appliances at once without worrying about the pressure dropping. They are also super-efficient.

So, what’s the catch? Well, they can be expensive and need to be checked regularly. Their complexity also means there is greater detail to their installation. They also need high mains pressure to function properly so if your local mains pressure is weak, this is not the system for you.

Where would a pressurised central heating system typically be used? Generally, in larger buildings and homes with multiple bathrooms, or where a lot of hot water is needed.

Do I have a system boiler? If you have a hot water cylinder but no tanks in the loft, then yes.

If you are in need of replacing or upgrading your central heating system, the Maintracts team would love to help! We can provide you with a quick quote, so you have some idea on what you need to plan and budget for. Alternatively, give us a call and we’ll take it from there – 020 8131 6267.