SU736887A3 - Method and device for control of heat-transferring unit preferably with circulating heat-carrier - Google Patents

Abstract

A central heating system employing a hot water flow has a temp. controller which automatically regulates temp. of the inlet flow as a function of return flow temp. Ambient and demanded temps. are included. A principal source of energy comprising solar panels (46) heats water in accumulator reservoir (31). Heat from a conventional burner (52) is transmitted via thermal exchange surfaces to the water in the reservoir (31). A control unit (42) with temp. sensors (38, 40) in the flow and return pipes controls the burner (52) to maintain temp. within upper and lower limits. A second reservoir (54) for domestic hot water (30) is heated by solar panels (46) and by a secondary energy source (74) which is controlled by a control unit (70) with temperature sensors (66, 68) in the flow and return circuits.

Description

. I ..,. ;. The invention relates to methods and devices for controlling a heat transfer installation, especially a central heating installation with a circulating coolant, preferably hot water, with a constant amount of circulating medium. A known method of controlling a heat transfer installation involves measuring and controlling the temperature in the supply and return pipes 1. There is another method of controlling the heat transfer installation, mainly with a constant circulating coolant, which involves measuring the temperature of the supply and return water 2. However, this method does not ensure optimal operation of the installation depending on heat consumption. The purpose of the invention is to increase the efficiency of the installation in operation. This is achieved by the fact that according to the proposed method of controlling the heat transfer plant, preferably with a constant circulating coolant, which measures the flow and return water temperatures, the temperature difference between the forward and return water is also measured and the flow temperature is changed. until the measured temperature difference between the supply and return water reaches the specified value of the difference between these temperatures, calculated from the dependences of the external temperature from circulating water temperature for supply and return pipelines. A device for carrying out the proposed method, including temperature sensors in the supply and return pipes, is equipped with sensors to achieve the minimum allowable temperature in the supply and return pipelines, the control unit, the time delay unit and the engine of the supply, return and circulating water mixing valve. Moreover, the temperature sensors in the supply and return pipes and sensors to achieve the minimum allowable temperature in the supply and return pipes are connected through the control unit and the time delay unit to the engine of the mixing valve of the supply, return and circulating water.

FIG. schematically shows an arrangement for implementing a method for controlling the installation of a central water heating system; in fig. 2 - installation of central heating to obtain water for domestic use, for example, for bathroom installations and heating of swimming pools.

The supply water flows through pipeline 1 from the heating boiler, which operates on coke or liquid fuel and provides the circulating water with a constant temperature. Through a four-way mixing valve 2, the circulating water enters the supply pipe 3, through which it is pumped through a heating network through a pump 4. The return pipe 5 also enters the mixing valve 2, from where the return water through line 6 enters the heating boiler or fully or partially returns to the supply pipe 3.

The four-way mixing valve 2 is controlled depending on the temperature difference between the supply and return water. The control is carried out using the control unit 7, to which the temperature values are supplied via the supply water temperature sensor 8 and the return water temperature sensor 9. Sensors 10 and 11 are also provided for the minimum allowable temperature in the supply and return pipelines, which are also connected to the control unit 7. The latter drives the engine 12, installing the mixing valve 2 in accordance with the set temperature difference so that the return water is mixed in the feed supply pipeline If the set temperature difference, e.g. 10 ° C, cannot be observed and the return / water is colder than the supply line by 8 ° C, the valve is reset, so that a large proportion of the return water is mixed with the water of the supply line. If, due to heat breakthrough, the energy return is so small that the difference control no longer works, all the return water is directed to the supply line until the circulating network water reaches the set minimum temperature, which is sensed by sensors 10 and 11 to the control unit 7. When the minimum temperature is reached, the operating mode of the installation fluctuates between this temperature and the pore; the HOB value is about 10 or 20 ° higher, until the energy consumption and control is minimized to empty temperature can be replaced by temperature difference control. The rise and decrease in the range of the minimum allowable temperature, in addition to thermal advantages, allows

 it is also more likely to actuate thermostat valves, for example, on the radiator, which is necessary to maintain the operation of these valves.

In order to avoid spontaneous increase in temperature when opening the mixing valve connecting line 1 to supply pipe 3, vent 2 is raised gradually by means of motor 12 by means of time delay unit 13 connected to control unit 7.

which, after a short time, turns off the engine 12 again. As a result, the noise in the heating system is significantly reduced, and a constant movement in the water circuit is ensured. It is assumed that the circulating water has a constant temperature, which, in accordance with the need, is reduced to a certain level by partial mixing with return water.

FIG. 2 shows a building 14 in which a water circuit is provided, represented by solid lines 15, and a domestic water circuit, represented by dashed lines 16.

Line 15 includes a water storage tank 17, from which water is discharged through pump 19 through pipeline 19, one or more consumers 20, and return pipe 21

.water. In the pipe 21, temperature sensors 22 and 23 are connected to the control unit 24 to determine the temperature difference.

In order to heat the water in the storage tank 17, solar collectors 26 are provided as the main energy source on the roof 25 of the building 14, by means of which the water is heated. For this purpose, through the solar collectors 25, as well as the storage tank 17, the

Circuit 27, driven by a circulation pump 28. With increasing heat demand, a second parallel-connected circulation pump 29 increases the flow of water through the solar collectors. Circulating pumps 28 and 29 are driven by control unit 24, depending on the temperature difference established by sensors 22 and 23. As an additional energy source, a conventional heating boiler 30 is provided, which transfers its heat through the surfaces of the heat exchanger to the water in the storage tank 17. The heating boiler 30 is automatically turned on and off by the control unit 24. Water for domestic consumption is supplied

in the same way as circulating net water.

Claims (2)

Line 16 includes a storage tank 31, a pipeline 32 leading to the water intake area 33, and a return pipeline 35 provided with a circulation pump 34. A return pipe 36 includes a pipeline 36, in which fresh water accumulates when water is collected for domestic use. Temperature sensors 37 and 38 detect the temperature difference in the supply and return lines and report them to an additional control unit 39, which automatically switches on and off the secondary energy. In the same way as in the installation with circulating mains water, heating can be carried out by means of the circuit 40 passing through the collectors 40 and through the boiler 41. Appropriate devices can be provided in both circuits to maintain the minimum allowable temperature. Claim 1. Method of controlling a heat transfer plant with preferably a constant circulating coolant, including measuring the flow and return water temperature, characterized in that, in order to increase the efficiency of the plant, the temperature difference between the forward and reverse water is also measured and the temperature is changed feed water, the temperature of the feed water being changed until the measured difference in temperature, supply and return water, reaches a predetermined value of the difference between these temperatures; calculated from the dependence of the external temperature on the temperature of the circulating water for supply and return pipelines. 2. An apparatus for carrying out the method according to claim 1, comprising temperature sensors in the supply and return pipelines, characterized in that it is equipped with sensors for achieving the minimum allowable temperature in the supply and return pipelines, the control unit, the time delay unit and the engine of the mixing valve supply, return and circulating water, and temperature sensors in the supply and return pipelines and sensors to achieve the minimum allowable temperature {) s in the supply and return pipelines are connected via b approx control unit and a time delay to the motor of the mixing fan flow, and reverse circulating water. Sources of information taken into account during the examination 1. USSR author's certificate No. 503033, cl. F 24 D 3/00, 1972. 2. Chistovich S. A. Automatic control of heat consumption in heat supply and heating systems. L., Stroyizdat, 1975, p. 93-94. . / 7 / 7 k 1, 0- "M -m