Radiators: History, Types, and How They Work

by Joost Nusselder | Updated on:  June 14, 2022
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Radiators are a type of convector used to heat a room or building. They contain fins made of steel or copper that transfer heat by convection from hot liquid inside the radiator to the air surrounding it. Cooler air then takes over the hot air’s place, thus creating a continuous cycle of convection.

Let’s dive a little deeper.

What are radiators

In this post we'll cover:

The Science Behind Radiators: Radiation and Convection

Radiation, convection, and conduction are the three major modes of heat transfer. In the case of radiators, radiation and convection are the two primary methods of heat transfer.

  • Radiation refers to the transfer of heat through electromagnetic waves. In radiators, this occurs when the elements within the radiator heat up and transfer heat to the surrounding air.
  • Convection, on the other hand, refers to the transfer of heat through the movement of fluids or gases. In radiators, this occurs when the heated air rises and carries heat away from the radiator, attracting cooler air to take its place.

How do Radiation and Convection Occur in Radiators?

Radiation and convection occur in radiators through a combination of elements and phases.

  • The radiator is filled with a liquid, typically water, which is pumped through a pair of exposed pipes.
  • As the liquid flows through the pipes, it is heated by the thermal exchange that occurs between the liquid and the cast iron or convector fins that make up the surface of the radiator.
  • As the liquid is heated, it begins to circulate through the radiator, carrying heat to the exterior portion of the device.
  • As the heated air rises, it attracts cooler air to the radiator, creating a flow of air that carries heat away from the device.

Why is Understanding Radiation and Convection Important for Radiator Maintenance?

Understanding radiation and convection is important for radiator maintenance because it can help you identify potential problems with your device.

  • If you notice that your radiator is not heating up properly, it could be due to a problem with the radiation or convection process.
  • By understanding how these processes work, you can identify potential issues, such as obstructed pipes or damaged fins, and take steps to address them before they cause further damage to your radiator.

The Evolution of Radiators: Tracing the History of Heating Buildings

As the 19th century progressed, radiators became increasingly popular and affordable. The Victorian era brought about elaborate and decorative designs, with radiators becoming a major feature in public buildings and larger homes. The Queen herself even paid a visit to the leading radiator production company of the time, Briggs and Co.

The Modern Radiator: From Wrought Iron to Sectional Cast Iron

The continuous advancement of radiators brought about the birth of the modern radiator. Franz San Galli, a Russian businessman, developed an early radiator in 1857. The earliest radiators were made of wrought iron, but as production methods improved, sectional cast iron radiators became the norm. These radiators were more affordable and easier to install, making them a popular choice for homes and buildings.

The Role of Radiators in Modern Buildings

Today, radiators play a major role in heating buildings. They come in a variety of styles and forms, from traditional cast iron radiators to modern electric radiators. Radiators are an efficient and effective way to heat a building, providing heat through radiation and convection. They are also easy to maintain and can last for many years with proper care.

Choosing the Ideal Radiator Type for Your Property

Traditional radiators are the most common type of radiator found in homes. They are usually made of steel and come in a variety of shapes and sizes. Some of the main features of traditional radiators include:

  • They are usually connected to a hot water system
  • They require natural convection to work
  • They come in a range of finishes, including chrome and other metallic looks
  • They are great for providing a quick and powerful heat output
  • They are relatively cheap to maintain and run

Electric Radiators

Electric radiators are a popular choice for those looking for a radiator that is easy to install and maintain. They work by converting electricity into heat and sending it out through the radiator. Some of the main features of electric radiators include:

  • They are fully self-contained and do not require any additional plumbing or connection to a hot water system
  • They come in a range of styles and finishes, including vintage and art deco designs
  • They are ideal for properties where running additional plumbing is not possible or would be too expensive
  • They are slightly more expensive to run compared to traditional radiators connected to a hot water system

Double Panel Radiators

Double panel radiators are a great choice for those looking for a radiator with a higher heat output. They work by having two panels of steel connected together, providing a larger surface area for heat to be emitted from. Some of the main features of double panel radiators include:

  • They are available in a range of sizes and finishes
  • They are ideal for larger rooms or properties with high ceilings
  • They are slightly more expensive to purchase compared to single panel radiators
  • They are a great choice for those looking to improve the energy efficiency of their property

Column Radiators

Column radiators are a great choice for those looking for a radiator with a vintage or traditional style. They work by having multiple columns of steel connected together, providing a larger surface area for heat to be emitted from. Some of the main features of column radiators include:

  • They are available in a range of sizes and finishes
  • They are ideal for properties with a traditional or period style
  • They are slightly more expensive to purchase compared to single panel radiators
  • They are a great focal point for any room and can add a touch of art to your property

Remember, the choice of radiator type depends on the size and construction of your property, as well as your personal preferences and aesthetics. It’s worth considering the different types available and understanding the methods of running and maintaining them before making a decision.

Heating: Staying Warm and Cozy During Bitter Cold Winters

Radiators and convectors are designed to transfer thermal energy from one medium to another for the purpose of space heating. They allow you to create a warmer and more comfortable environment in your home during frigid winters and cold breezes blowing in from the lake. Here are some benefits of using radiators and convectors for heating your property:

  • Radiators and convectors are commonly used in homes as a reliable and necessary source of warmth during the colder months.
  • They are designed to lower energy consumption and supply additional benefits such as improved airflow and quiet working behind the scenes.
  • Radiators and convectors are also easy to maintain and are a cost-effective way to heat your home.
  • They are commonly powered by a furnace or boiler, which turns on and off as necessary to keep the temperature fluctuations to a minimum.
  • Radiators and convectors give you a cozy feeling as warm air blows out of the registers and enters the room, helping you stay warm and comfortable for hours on end.

Choosing the Right Radiator or Convector for Your Home

If you’re ready to purchase a radiator or convector for your home, here are some things to keep in mind:

  • Consider the size of the room you want to heat, as well as the layout and design of your home.
  • Think about the temperature fluctuations you can expect in your area, as well as the average temperature you want to stay at.
  • Decide whether you want a radiator or a convector, and whether you want one that blows warm air or circulates it more quietly.
  • Don’t hesitate to discuss your options with a heating professional, who can help you find the perfect radiator or convector for your needs.

Keeping Your Engine Cool: The Role of Radiators

Radiators are heat exchangers that play a crucial role in cooling internal combustion engines. They work by transferring heat from the engine to the surrounding air through a process of convection. As the engine heats up, coolant flows through the radiator, where it is cooled by the air passing over the fins. This cooled coolant then returns to the engine to absorb more heat, completing the cycle.

Why is Engine Cooling Important?

Engine cooling is essential for the proper functioning of an internal combustion engine. Without adequate cooling, the engine can overheat, causing damage to the pistons, cylinder walls, and other components. Overheating can also lead to engine failure and even fires, making proper cooling a matter of safety as well as performance.

Where are Radiators Used?

Radiators are used in a variety of applications, including:

  • Automobiles: Most cars and trucks use radiators to cool their engines.
  • Railway locomotives: Radiators are used to cool the engines of diesel-electric locomotives.
  • Stationary generating plant: Radiators are used to cool the engines of generators used in power plants.
  • Other internal combustion engines: Radiators are used in a variety of other applications, including motorcycles and piston-engined aircraft.

What are the Benefits of Radiators?

Radiators offer a number of benefits, including:

  • Efficient cooling: Radiators are highly efficient at transferring heat from the engine to the surrounding air, helping to keep the engine at a safe operating temperature.
  • Reliability: Radiators are simple, reliable components that require little maintenance and can last for many years.
  • Versatility: Radiators can be used in a wide range of applications, making them a versatile choice for engine cooling.

How Can You Maintain Your Radiator?

To keep your radiator working properly, it’s important to:

  • Check the coolant level regularly and top it up as needed.
  • Inspect the radiator for damage, leaks, and other issues.
  • Clean the radiator fins and other components to ensure proper airflow.
  • Replace the radiator if it becomes damaged or worn out.

Understanding the Inner Workings of Radiators

Radiators are an essential part of our lives, especially during the colder months. But how do they work? Here’s a breakdown of the process:

  • Radiators work by drawing heat from water or steam and use that heat to warm up surrounding air.
  • The hot water or steam flows through the radiator, and the metal body of the radiator allows the heat to be effectively transferred to the surrounding air.
  • This process is repeated, allowing the radiator to continuously produce heat and warm up the room.
  • Traditional radiators are built with metal because it is an excellent conductor of heat.
  • There are different types of radiators, including hot water and steam radiators, each with its own method of heating.
  • Hot water radiators typically require a boiler to heat the water, while steam radiators use a special type of boiler to generate steam.
  • Electric radiators work by passing an electrical current through an element, which gets hot and starts to produce heat.
  • Knowing the type of radiator you have is essential when it comes to understanding how it works and how to maintain it.

The Different Types of Radiators

Despite the obvious benefits of radiators, there are a couple of different versions to choose from:

  • Standalone radiators are the typical type of radiator that most people are familiar with. They are small and can be placed anywhere in the room.
  • Center heating radiators are designed to keep the entire room warm and are typically installed by a professional.
  • The material used to build the radiator is also important. High-quality materials like cast iron or aluminum can create a more efficient radiator.

Understanding the Process: How Electric Radiators Deliver Heat

There are several types of electric radiators available, including:

  • Thermal Fluid Radiators: These radiators contain a fluid that is heated by an internal element. The fluid then heats the surrounding air, providing warmth to the room.
  • Dry Element Radiators: These radiators contain an internal element that heats up and delivers heat directly to the surrounding air.
  • Storage Radiators: These radiators store heat during off-peak times and then release it during peak times, providing warmth when it is needed.

What is the Process of Repeated Heating and Cooling Called?

The process of repeated heating and cooling is called thermal cycling. This process can cause wear and tear on electric radiators over time, so it is important to choose a high-quality radiator that can perform well over the long term.

What is the Degree of Heat Delivered by Electric Radiators?

The degree of heat delivered by electric radiators can vary depending on the type of radiator and the size of the room. However, most electric radiators can deliver heat in the range of 60-80 degrees Fahrenheit.

What is the Most Popular Type of Electric Radiator?

The most popular type of electric radiator is the dry element radiator. This type of radiator is convenient and easy to use, making it a popular choice for many homeowners.

Understanding the Two Valves on Your Radiator

The two valves on a radiator are essential for controlling the flow of hot water that enters and exits the radiator. The first valve, typically called the ‘wheel valve,’ allows you to turn the heat up or down by controlling the amount of hot water that enters the radiator. The second valve, known as the ‘lockshield valve,’ balances the system by controlling how much heat comes out of your radiator. Together, these valves enable you to adjust the temperature of your radiator to ensure that your home is heated evenly.

Why are these valves important?

Having properly functioning valves on your radiator is crucial for a few reasons:

  • Safety: If your radiator is overheating, it can become a safety hazard. The valves allow you to control the temperature and prevent accidents.
  • Money-saving: By controlling the amount of hot water that enters your radiator, you can lower your energy bills and save money.
  • Comfort: The valves allow you to set the temperature to your desired level, ensuring that you are comfortable in your home.
  • System maintenance: Properly functioning valves help maintain the health of your heating system, preventing costly repairs down the line.

How do these valves work?

The wheel valve works by allowing hot water to enter the radiator when turned on, and shutting off the flow when turned off. The lockshield valve, on the other hand, controls the amount of hot water that exits the radiator, ensuring that the heat is distributed evenly throughout your home. It’s important to note that these valves need to be set properly to ensure that your heating system is working efficiently.

What should you do if you’re having issues with your valves?

If you’re having issues with your radiator valves, it’s best to call a professional to come and take a look. A local heating company can help you diagnose the issue and offer solutions to get your system back up and running. Before calling, make sure to do some research to find a reputable company in your area. Look for reviews and check their credentials to confirm that they are a good fit for your needs.

What are some tips for maintaining your valves?

To ensure that your valves are working properly, follow these tips:

  • Check your valves regularly to make sure they are working correctly.
  • Complete any necessary repairs or replacements promptly.
  • Choose a reputable company to help you with maintenance and repairs.
  • Confirm that your valves are set correctly to ensure that your heating system is working efficiently.
  • Offer your valves a bit of TLC by wiping them down with a towel to keep them clean and free of debris.

In the end, having properly functioning valves on your radiator is essential for maintaining a comfortable and safe home. By understanding how they work and taking the time to maintain them, you can ensure that your heating system is working efficiently and saving you money in the long run.

Why Radiator Heaters are a Great Choice for Your Home

  • Radiator heaters are a type of heating system that uses hot water or steam to heat your home.
  • Unlike forced-air systems, radiator heaters do not produce a breeze, which means you can feel warmer at a lower temperature.
  • Radiator heaters are also much quieter than furnaces, as there is no forced-air component to hot water heating.
  • Radiator heaters are equipped with safety features that prevent them from overheating or causing fires.
  • Electric radiator heaters are a better option for those who want to cut down on their power usage, as they are more energy-efficient than other types of electric heaters.
  • Radiator heaters are extremely versatile and can be built in different materials and forms to fit any room size or style.
  • Radiator heaters require little maintenance, making them a cost-effective option in the long run.
  • Radiator heaters are able to effectively heat a room without having to constantly start and stop, which ultimately cuts down on energy usage and extends the life of the unit.

Choosing the Right Type of Radiator Heater

  • There are different types of radiator heaters, including hot water and steam versions.
  • Hot water radiator heaters are the most typical and are able to effectively heat a room by supplying a constant flow of hot water.
  • Steam radiator heaters utilize a different process, where steam is produced and then circulated through the radiator element to heat the room.
  • When choosing a radiator heater, it’s important to consider the size of the room, the level of heat needed, and the type of radiator that will be most effective.
  • It’s also worth doing research on different brands and models to make sure you’re getting the best possible option for your money.

The Unfortunate Downsides of Radiator Heaters

Radiators can be noisy, especially when they start to age. The constant clanging and hissing can be a real annoyance, especially if you’re trying to concentrate or sleep. It’s not just the sound of the radiator itself either, as the pipes can also make noise as the hot water flows through them.

Cluttered Rooms

Radiators can take up a lot of space in a room, which can be a problem if you’re already short on space. They can also be an eyesore, especially if they’re old and rusty. If you’re trying to create a minimalist look in your home, radiators can really ruin the aesthetic.

Draughts and Cold Spots

Radiators can cause draughts and cold spots in a room, which can be uncomfortable and make it difficult to maintain a consistent temperature. This is because radiators work by heating the air around them, which then rises and creates a convection current. This can cause cold air to be drawn into the room from outside, which can be particularly noticeable if you have poorly insulated windows or doors.

Expensive to Run

Radiators can be expensive to run, especially if you have an older model. This is because they rely on hot water or steam to heat the air, which requires a lot of energy. If you’re looking to save money on your heating bills, a radiator may not be the best option.

The Portable Alternative

If you’re looking for a heating solution that doesn’t suffer from any of these downsides, you might want to consider a portable heater. These heaters are compact, easy to move around, and don’t require any installation. They’re also much quieter than radiators and can be a lot cheaper to run. Plus, they don’t clutter up your room or cause draughts and cold spots.

Ways to Keep Your Radiator in Tip-Top Shape

Maintaining your car’s radiator is crucial to ensure that it functions properly. Neglecting its upkeep can lead to costly repairs and even engine failure. Here are some reasons why maintaining your radiator is important:

  • A properly maintained radiator helps regulate your engine’s temperature, preventing overheating and engine damage.
  • Radiators that are not maintained can accumulate residue inside, which can lead to clogs and blockages, reducing the radiator’s efficiency.
  • Regular maintenance can stop small issues from becoming bigger problems, saving you time and money in the long run.

Basics of Repairing Radiators

If you notice any issues with your radiator, it’s best to get it repaired as soon as possible. Here are some basics of repairing radiators:

  • If your radiator is leaking, it may be due to a damaged hose or a crack in the radiator itself. A professional mechanic can diagnose the issue and repair it.
  • If your radiator is clogged, it may need to be flushed or replaced.
  • If your radiator is damaged beyond repair, it may need to be replaced entirely.

Remember, regular maintenance is key to keeping your radiator in good condition and preventing costly repairs.

Hot Water vs Steam Radiator: What Makes Them Different?

The major difference between hot water and steam radiators is the heating system they utilize. Hot water radiators have water that is heated from a central boiler continually flowing through them, while steam radiators have steam produced by a boiler that flows through the piping leading to the unit.


Hot water radiators are more efficient than steam radiators because they don’t require as much heat to produce the same amount of warmth. Hot water radiators also provide a more even heat distribution throughout the room, making them a more reliable option.


Both types of radiators require proper maintenance to function properly. However, hot water radiators are easier to maintain and fix compared to steam radiators. Hot water radiators have fewer moving parts, making them less prone to problems caused by piping and valves. On the other hand, steam radiators can encounter issues caused by air trapped in the system, leading to noisy and inefficient heating.


Hot water radiators are compatible with modern heating systems, such as gas and electric boilers. Steam radiators, on the other hand, are more commonly found in old buildings and homes that were originally built to utilize coal or wood as a heating source. Converting a steam radiator to a hot water system can be costly and time-consuming.

Replacement and Repair

When it comes to replacements and repairs, hot water radiators are easier and cheaper to replace than steam radiators. Hot water radiators can be easily disconnected and replaced without causing any damage to the rest of the heating system. Steam radiators, on the other hand, require professional help to replace or repair, and the process can be costly.


One common problem that people encounter with steam radiators is noise caused by the steam trap and valve. This issue can be fixed by bleeding the radiator to release any trapped air or replacing the valve. Hot water radiators, on the other hand, rarely produce any noise.

Warped Radiator

Another issue that can occur with steam radiators is a warped radiator caused by condensate buildup. This problem can be fixed by cleaning the radiator or replacing it entirely. Hot water radiators, on the other hand, rarely encounter this issue.


So, radiators are a way to heat a building using convection and radiation. They’re not as popular as they used to be, but they’re still used in many buildings. 

You should now know the ins and outs of radiators, so you can make the right decision when it comes to heating your home.

I'm Joost Nusselder, the founder of Tools Doctor, content marketer, and dad. I love trying out new equipment, and together with my team I've been creating in-depth blog articles since 2016 to help loyal readers with tools & crafting tips.