The manufacturers of heating system equipment have created units of connecting radiators in many different shapes and for various purposes.
For one-sided connection of radiators in systems with one-piped horizontal setting, special two-way units of connection with built-in bypass are manufactured (see Figure 94). In the lower part of the unit, the bypass is located which divides the hot warmth carrier, directing one of its parts into the radiator and the other part back to the pipeline. Units of connection are made in two types: with a balancing valve and without it. By screwing and unscrewing the valve, the supply of warmth carrier flowing from the radiator is regulated. Setting the balancing valve is done according to the charts of the manufacturer of the connection unit. In the high part of the unit, a thermostat is located which monitors the air temperature in the room and which shuts off the supply of warmth carrier into the radiator.
For two-piped heating systems almost the same unit was created by the manufacturers of heating equipment (see Figure 95). The only difference lies in the fact that the bypass of the two-piped unit is always closed. Different technical solutions make this possible, in this case, by the gasket on the valve stem. It should be noted that there are a lot of manufacturers of radiator connection units.
In Figures 94 and 95, the units of the company «Heimeier» are presented. Other companies use other technical solutions but the same main principles are used in them: low connection of pipelines to the unit, built-in bypasses and balancing valves.
There are universal radiator connection units (see Figure 96) with regulative built-in bypass which are designed both for one-piped and two-piped horizontal settings. By opening the bypass valve the flow of hot warmth carrier into the return pipeline is regulated. Complete closing of the hole in the bypass sends all the warmth carrier into the radiator. Partial opening divides the warmth carrier into two streams: one part is directed into the radiator, the other part into the pipeline and since the cone valves are located on one stem then it becomes possible to balance the heating contour, making the supply through the radiators more in the further heating and less in the closer ones.
To make the heating radiators more aesthetically appearing, the number of connecting nodes can be decreased and a so-called «single-point connection» is used (see Figure 97). Its main feature is the use of a special tube that is inserted into the radiator. Through this tube the hot warmth carrier is delivered deeply into the radiator and the cooled warmth carrier is removed through a hole which is located around the tube; or conversely, the hot warmth carrier is inserted through the hole and removed through the tube. These units of radiator connections are designed for both one-piped and two-piped horizontal settings of heating contours.
For some types of radiators, pipeline connections can be made in the low plane of the heating device. Special connection units have been invented for them by manufacturers of heating equipment. As with side radiator connections, they are made with a built-in regulative or non-regulative bypass and a balancing valve (see Figure 98).