In addition to the presented simple solutions of convectors, so-called. fan climate coils (also called valves). They have a built-in fan that draws air from the outside or from the room, depending on the position of the flap in the convector chamber. Fan convectors are characterized by high thermal efficiency. With their help, you can not only heat, but also ventilate the rooms. Noise associated with the operation of the fan can be annoying. They are sometimes used in public utility buildings, such as hotels, restaurants, administrative premises, e.t.c.
Fan convector. Marks: 1 – flap, 2 – filter , 3 – fan, 4 – air heater, 5 – outdoor air, 6 – indoor air, 7 – air supply to the room.
As the air flow rate through the convector casing increases, the intensity of heat transfer by convection also increases. The increase in speed is advantageous in view of the reduced deposition of dust on the surface of the finned heating cable. However, this increase also means an increase in flow resistance. A number of requirements are imposed on the construction of convectors: increasing the spacing between the heating ribs (4-7 Mm), selection of streamlined shapes of pipes and installation of blades on the air inflow and outflow or enlarging the area of inlet cross-sections. Fan coil units are rarely used for space heating. Much more often they are used as the so-called. convector heaters, donating approx 80% heat by convection. They can be free-standing, have its own power system (for example. from the electricity network) or be connected to the pipes of the heating system.
Among the frequently used are Convector heaters. Compared to cast iron section heaters, they have a lower surface temperature and a low water capacity. For example, for a radiator with a heat output of approx 1300 The water capacity is approx 0,4 dm3, and the water capacity of a traditional radiator, of the same strength, is 10-15 times greater. Means, that by using heaters with a small water capacity it is possible to reduce the amount of heating medium in the central heating system (for example. with 400 dm3na 40 dm3). Low water capacity also means low heating system inertia. The technical data of the solutions called GPM and GCM are summarized in the table.
Technical data of type heaters GPM i GCM-Prestige Plus
These heaters are also characterized by a well-developed heating surface. GPM types are side-fed heaters, a GCM with bottom flow and built-in thermostatic valve. Their maximum working pressure reaches 1 MPa (on request to 5 MPa), and maximum operating temperature +95°C.