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How to choose the right convector?

Basic information about choosing convectors

It is important to choose between the basic parameters

Why heat with convectors? Convectors use airflow to heat. Unlike other types of heating, they are easy to install and maintain and offer great shape variation. Some types of convectors can also be used for cooling. Why use a convector and not a radiator? Convectors contain only a small amount of water. Compared to radiators, they heat rooms significantly faster and use less energy. Another difference is the optimal heat distribution. Unlike radiators, convectors do not radiate heat into the wall, allowing it to be distributed efficiently throughout the room. Due to their design and method of operation, they are ideal under french windows and large glass surfaces. The best-selling convectors are fanless with natural convection. Another type is fan-assisted convector which serves mainly for heating but some types also for cooling.

Trench convector – InFloor

BOKI trench convectors are the perfect solution for any building where both aesthetics and functionality are needed. Due to the installation in the floor, this type of convectors is most often used in combination with french windows or large glazed surfaces. An immense advantage of these convectors is the small amount of water in the heat exchanger (compared to conventional radiators), which ensures fast heating of the room. Their installation in the floor makes them an optimal source of heat circulation in the room.
See InFloor convectors

Free-standing convectors

BOKI free-standing convectors are the perfect solution for those who need to achieve high output. Thanks to their construction, the convectors are installed 10 cm above the floor, which ensures even greater air circulation and thus greater convectors output. Thanks to the low height, the convectors can be used in rooms with large glass surfaces as well as in rooms with protruding windows. Thanks to the unlimited colour options, they can fit perfectly into any interior.
See free-standing convectors

Basic parameters of convectors

Trench convectors are divided into two basic groups: without fans (natural convection) and with fans (forced convection). Fanless convectors operate on the principle of natural convection. In this case, the convector is heated by the flowing water, releasing heat which has the natural function of rising upwards. Convectors with fans work with forced convection. In this case, the air heated by the heat exchanger is blown into the room by the fan. Convectors can come in different dimensions, outputs or types of ducts. They are supplied together with a grille. This can be stainless steel, aluminium in different colours or wooden (beech, oak).

Dimensions of convector

Each convector is dimensionally defined by its width, length and height. The dimensions of each convector can be found in the "Dimensions and connections" section.

Dimensions of the body

Depending on the dimensions, the convector is equipped with a certain type of heat exchanger and fan. Hence its heat output, given in Watts. The heat output varies depending on the temperature gradient. This indicates the inlet water temperature / outlet water temperature / desired room temperature. The most commonly used temperature gradient is 75/65/20 °C.

Temperature gradient

The temperature gradient, expressed in degrees Celsius, consists of three parameters: inlet water temperature / outlet water temperature / desired room temperature. Depending on this temperature gradient, the performance of the convector is determined. The most commonly used temperature gradient is 75/65/20 °C. Is the temperature gradient not suitable for you? Use the conversion calculator on our website.

Type of duct

The ducts of the convectors can be made of different materials. The most common is double-sided galvanized sheet painted in RAL 9005 black. There is also brushed stainless steel sheet according to DIN 1.4301. For pool environments, stainless steel sheet according to DIN 1.4404 is used. The duct can also be supplied with a set for height adjustment of the convector. Another option is the installation of flanges for external air supply.

Type of grille

In terms of type, the grille can be

1. Roll-up (transverse)

the slats together with the spacer rings are strung on a spring

suitable for all slat materials and all types and sizes of convectors

2. Rigid (linear, longitudinal)

made of duralumin or stainless steel slats only

supplied together with the grid support

cannot be used for convectors with fans (F1S, F2C, F2V, F4C, F4V)

Questions and answers about choosing a convector

You may find your answers here

For the smooth use of convectors, boilers for gas, biomass or solid fuels, electric boilers, heat pumps, district heating systems are required - in short, central heating. Convectors are not suitable for so-called stand-alone systems where a forced circulation pump is not used.

In most cases, yes, but you need to pay enough attention to choose the right convector. When determining its type and size, we must be guided by the purpose and the space available. The heat loss of the room, the temperature of the heating water etc. are also important.

First of all, the floor composition is important, which determines the building height of the convector, and then the heat loss of the room, which determines the choice of the type of convector. Carefully select the location of the thermostat and transformer, which are part of the electrical control (convectors with a fan). It is also essential to know the final type of floor covering and its colour (important for the choice of grilles and frames).

The advantage of convectors with a fan is their high performance and fast response - they are therefore designed primarily for conventional heating. Convectors without a fan are mainly suitable for rooms with lower heat consumption. In the case of fanless convectors, a temperature screen is created in front of the cooler glazed wall, thus ensuring thermal comfort in the room.

The convectors with a fan are supplied only with a safe voltage of 12 V and are also protected by a grille against the penetration of external objects. This prevents children from being injured. Even if a child were able to stick his or her finger through the grille, the motor is so weak so the child would not be injured.