Last Updated: Sunday, 11th February 2024

Your Central Heating System Explained

Central heating systems have become an integral part of modern homes, ensuring a warm and cozy environment. If you are interested to understand how yours works, we'll be discussing it all here.

Understanding the Central Heating System

Central heating systems are designed to produce heat from a singular source, typically a boiler, and distribute it throughout a home in the form of hot water or air. The majority of homes in the UK are equipped with Wet Central Heating Systems, powered by hot water and radiators.

Professional installation of these systems is essential, however homeowners can undertake basic maintenance tasks if they grasp the underlying principles. We'll discuss how the pipework works, how the heat moves through to radiators and your rooms and finally how you can control the temperature of your home.

Pipework Essentials

In the UK, pipework can come in three forms. We'll discuss these now:

Single Pipe and Flow and Return Systems

Central heating systems play a crucial role in maintaining indoor comfort by distributing heated water from a boiler to radiators throughout a building. These radiators, in turn, release heat into rooms, ensuring a cozy environment.

Diagram explaining the difference between single pipe and flow and return heating systems in the home

The diagram provided shows the two most common types of plumbing configurations for central heating systems. Historically, a single pipe was used to connect radiators. However, modern systems employ a more efficient flow and return design. In this setup, hot water is pumped from the source to each radiator's entry point, reaching the last radiator in the sequence. Simultaneously, a 'return pipe' collects cooled water from the radiators, transporting it back to the boiler for reheating.

Microbore Systems

Another system to consider is the Microbore approach. With this system, the flow and return mechanism leads to a manifold, which branches off into narrower pipes measuring 8 to 10mm. These smaller pipes are then dedicated to supplying individual radiators on their separate circuits.

Diagram showing a microbore manifold radiator system

One of the perks of Microbore is its simplified installation process. The smaller pipe diameter, available in flexible coils, makes manoeuvring under floors and through confined spaces a breeze.


As discussed in this article, the fundamental concept of a central heating system is to distribute heat to radiators to warm your home. Radiators accomplish this by using the hot water to initiating convection currents in your rooms, efficiently dispersion that heat around your room.

Learn how radiators work here

Controlling the Temperature

Heating controls are the final piece of the puzzle. They are the components that allow homeowners to regulate the temperature of their homes. They determine when the heating turns on and off and at what temperature. These controls are essential for ensuring that the heating system operates efficiently, saving both energy and money.

Types of Heating Controls

  1. Room Thermostats
    These are the most common heating control around. They work by detecting the ambient air temperature in a room. When the temperature drops below the set level, the thermostat signals the boiler to start, and when the desired temperature is achieved, it instructs the boiler to stop. They can be placed anywhere in the home.

  2. Boiler Programmers
    These are timers that allow homeowners to set specific times for the heating system to operate. Some sophisticated models even allow different settings for weekdays and weekends, but usually this is one of the least preferred options as it is the least efficient and least flexible.

  3. Hot Water Cylinder Thermostats
    This is specifically for systems with a hot water storage cylinder. These thermostats regulate the temperature of the water in the cylinder and ensure that the water is neither too hot nor too cold. They can either let more hot water in from a heat exchanger, or they can trigger an immersion heater to directly heat the water inside the cylinder.

  4. Thermostatic Radiator Valves (TRVs)
    TRVs are usually used in combination with thermostats. They are valves fitted to radiators, allowing individual control of the temperature in each room. They self-regulate the flow of hot water to the radiator it is connected to based on the room's temperature.

  5. Smart Thermostats & TRVs
    These are the future of heating controls. Smart thermostats and TRVs, can be controlled remotely using smartphone apps. They can learn your heating preferences over time and adjust settings accordingly. Some even use geolocation to determine when you're on your way home and adjust the heating accordingly. They are designed to help you use the least energy possible when keeping your home warm.

The Importance of Heating Controls

Having the right heating controls in place can lead to significant savings on energy bills. For instance, reducing your room temperature by just one degree can lead to a 10% savings on your heating bill. Moreover, with advanced controls, homeowners can ensure that they heat only the rooms they use, further enhancing efficiency.

Any more questions?

If you have any queries or questions about the products we sell, or even your next project, give us a shout! We'll try our best to give you a hand.