Difference Radiant Heat versus Convective Heat

Whether a room climate is comfortable or not is not determined solely by the room temperature. What is important is how the heat is absorbed by the person. Because: Heating not only influences the room temperature, it changes the entire room climate.

In general, there are two different types of heat transfer in enclosed spaces. While radiators transfer heat to the room through convection, surface heating systems work with radiant heat. But what is the difference?

Difference Radiant Heat versus Convective Heat

Whether a room climate is comfortable or not is not determined solely by the room temperature. What is important is how the heat is absorbed by the person. Because: Heating not only influences the room temperature, it changes the entire room climate.

In general, there are two different types of heat transfer in enclosed spaces. While radiators transfer heat to the room through convection, surface heating systems work with radiant heat. But what is the difference?

Which heating emits convection heat and which radiant heat?

Conventional radiators, air heaters, and convectors mostly work with convective heat. Surface heating (wall, floor, ceiling) and tiled stoves warm the room pleasantly and comfortably using soothing radiant heat. The heat is transferred directly from the surface to the body. 

Which heating emits convection heat and which radiant heat?

Conventional radiators, air heaters, and convectors mostly work with convection heat. Surface heating (wall, floor, ceiling) and tiled stoves warm the room pleasantly and comfortably with soothing radiant heat. The heat is transferred directly from the surface to the body. 

What is Radiant Heat?

Radiant heat can be compared to sunlight: When infrared rays hit a solid object, it is set into faster vibration and warms up. This energy is released as heat into the room. Thus, a person is warmed "from within."

Who doesn't know this? When sitting in the sun in a ski lodge in winter, a T-shirt is usually enough. In the shade, however, you need a ski jacket to avoid getting cold. 

What is Radiant Heat?

Radiant Heat can be compared to sunlight: When infrared rays hit a solid object, it is set into faster vibration and warms up. This energy is released into the room as heat. Thus, a person is warmed "from within."

Who doesn't know this? When sitting in the sun in a ski lodge in winter, a T-shirt is usually enough. In the shade, however, you need the ski jacket to avoid getting cold. 

Why does the wall heating, compared to the underfloor heating, act more as a radiant heater?

The rays spread out at a right angle to the surface. Humans are in direct radiation exchange with the floor with only a small percentage of the possible skin surface. In comparison, the radiation exchange with wall heating is higher, which is why wall heating is often perceived as more comfortable. 

Why does the wall heating, compared to the underfloor heating, act more as a radiant heater?

The rays spread out at a right angle to the surface. Humans are in direct radiation exchange with the floor with only a small percentage of the possible skin surface. In comparison, the radiation exchange with wall heating is higher, which is why wall heating is often perceived as more comfortable.

Advantages of Radiant Heat

The warmth is perceived as very comfortable.

The room air is gently heated and distributed, the humidity remains almost the same, and there is hardly any turbulence in the air. The room air temperature is perceived as higher with radiant heat than it actually is, as the heat is transferred directly to the body.  

The temperature in the room can be reduced by up to 2 °C. 

Each degree lowered saves around 6% in heating costs per year.

The radiation system also works for cooling in the summer.

The radiation system also works for cooling in the summer. The cool water circulates in the pipes, cooling the wall and ceiling surfaces. Through radiation exchange, heat is extracted from the body. This makes it pleasantly cool in the summer. 

Radiant heat is perceived as more pleasant compared to convection heat. However, it takes a little longer to become available. 

What is convective heat?

Convective heat warms the air and distributes it in the room. The heat is transferred from one place to another by means of convection. The air thus acts as the heat carrier. This often creates drafts in the room, which are perceived as unpleasant.

A convector moves the air and thus stirs up dust. This can be unpleasant for allergy sufferers. 

What is convection heat?

Convective heat warms the air and distributes it in the room. The heat is transferred from one place to another by means of convection. The air thus acts as the heat carrier. This often creates drafts in the room, which are perceived as unpleasant.

A convector moves the air and thus stirs up dust. This can be unpleasant for allergy sufferers. 

Advantages and Disadvantages of Convection Heat

The advantage of convection heat is that the heat is quickly available and spreads rapidly throughout the room. The disadvantage is that different temperature zones are created in the room. The warm air rises and the cold air sinks. This means: warm head and cold feet, even if the room temperature is quite high. The room does not become comfortable.

Advantages and Disadvantages of Convection Heat

The advantage of convection heat is that the warmth is quickly available and spreads rapidly throughout the room. The disadvantage is that different temperature zones are created in the room. The warm air rises, and the cold air sinks. This means: warm head and cold feet, even if the room temperature is quite high. The room does not become comfortable.

What is better: Surface heating or convector heating?

This question is clearly answered with "surface heating." In addition to the aforementioned advantages, it is a forward-looking and sustainable heating system. Since it heats over a large area, it can be operated with low flow temperatures of 25 °C to a maximum of 38 °C. Conventional radiators operate at a flow temperature of about 60 °C due to their small size. Thus, surface heating not only saves real money but also protects our environment.

What is better: Surface heating or convector heating?

This question can clearly be answered with "surface heating." In addition to the aforementioned advantages, it is a forward-looking and sustainable heating. Since it heats over a large area, it can be operated with low flow temperatures of 25 °C to a maximum of 38 °C. Conventional radiators operate at a flow temperature of about 60 °C due to their small size. Thus, surface heating not only saves real money but also protects our environment.