LT3412B - Method for regulation for hot-water heating system - Google Patents

Abstract

This invention belongs to heating techniques, more specifically, to the automatic adjustment of heating water systems.The purpose of this invention is to economize the energy used for heating.By implementing this method, the temperatures of air and water, which is fed into the heating system, and of water returning from the heating system, are measured. The new thing is that the feeding water temperature reliance on the outside temperature is adjusted by the desirable size of the feeding water temperature for each optional time interval, the feeding water temperature is kept equal to the adjusted temperature, and the circulating pump is switched on when the measured feeding and returning water temperature difference exceeds the proper one, according to the calculated difference of the adjusted feeding water temperature.

Description

The invention relates to heating technology, more particularly to automatic regulation of heating water systems.

Known heating control device (USSR a.l. No.1218262), which regulates the temperature of the water supplied to the heating system depending on the outdoor temperature and operates only with forced circulation of heating water.

The known device is low-cost due to the constant, constant dependence of the supply water temperature and the outdoor temperature, and the constant operation of the circulating pump.

A known method of heating control (USSR a.l. No. 1241029), in which the circulation pump is switched off periodically depending on the temperature of the heated room.

This method is low-cost, regulating heating in objects having several rooms with different thermal characteristics.

The closest to the proposed method is the method of regulating the heating water system (USSR a.l. No. 524044), which measures the temperature of the outdoor air, the water supplied to the heating system and the return water from the heating system and regulates the temperature of the supply water. The temperature of the supply water is regulated by a constant dependence of the difference between the supply and return temperatures on the outside temperature.

This method of regulation is quite versatile, but due to the constant difference between the supply and return temperatures, it is not economical to depend on the outdoor temperature. In addition, this method does not provide control of the circulation pump.

FIG.

The object of the invention is to save energy for heating.

The aim is achieved by adjusting the dependence of the outdoor water temperature on the desired supply temperature by adjusting the temperature of the outdoor water, the supply water to the heating system and the return temperature of the heating system by adjusting the supply temperature to each freely for a selected time interval, the supply water temperature is maintained at this adjusted temperature value, and the circulation pump is switched on when the measured difference between the supply and return water temperatures exceeds the required value calculated from the adjusted supply temperature.

The newly introduced operations - time-programmed temperature correction and position control of the pump depending on the temperature difference - are not substantially new and are known in various software and automatic control units. The main difference between the proposed methods is that the whole of the listed operations, when applied to regulate heating, gives a new feature - the energy efficiency of the heating system - which is not a consequence of any single operation. The following example illustrates how this method can save energy consumption for heating.

FIG. - a schematic diagram of a heating system implementing the proposed method and a variant of a supply water temperature control unit are shown.

The heating system comprises supply water temperature control unit 1, supply water pipe 2, return water pipe 3, circulation pump 4, heating devices 5, supply water temperature sensor 6, return water temperature sensor 7, outdoor air temperature sensor 8, regulator 9. Supply temperature The water temperature control unit 1 is comprised of actuators which change the temperature of the supply water according to the commands of the controller 9. This can be an adjustable heat source such as an electric or gas water heater. Using an unregulated heat source (solid fuel boiler, centralized heat supply), the temperature control unit of the supplied water can be realized according to Fig. 2. a circuit comprising an unregulated heat source 10, a water mixing valve 11 with an electric actuator 12.

As the method is implemented, the temperature of the outdoor air, the supply water and the return water is measured continuously or periodically. The desired supply temperature is calculated from the measured outdoor temperature and the dependence of the supply water temperature permanently programmed on the controller with the outdoor temperature (heating schedule). The controller stores a user-defined flow temperature correction program for each time interval of a certain duration, for example, for each hour of the day. This correction program is designed based on the purpose and usage characteristics of the heated object. For example, industrial premises are programmed to reduce the supply water temperature during non-working hours and increase prior to commencement of work, for residential premises to program the night-time temperature reduction.

The controller adds (subtracts) the temperature correction value corresponding to the current period read from the memory to the required supply temperature according to the heating schedule. This calculates the adjusted required supply water temperature. The controller maintains the supply water temperature in accordance with the well-known principle of stabilization of the parameter (temperature) with this adjusted required supply water temperature.

The regulator calculates the required difference between the supply and return water temperatures, based on the adjusted value of the required supply water temperature, compares the difference between the supply and return water temperatures according to the permanently programmed supply and return water temperature dependencies and actuates a circulating pump in the well-known principle of two-position control when the measured difference exceeds the required.

This maintains the supply water temperature in accordance with the heating schedule and the user-defined supply water temperature correction for each period, and the circulation pump is switched on when the measured supply and return water temperatures exceed the required. When designing the supply water temperature adjustment program, the user is guided by the desired change in the temperature regime of the heated object and the relationship between the change of the supply water temperature and the temperature of the heated object. This dependence is approximated by the design of the heating system and corrected during operation. For example, to change the temperature in a living room by 1 ° C, the supply water temperature should be changed by about 3 ° C.

The proposed method of regulating water heating allows saving energy consumption by adjusting the supply water temperature by optimally adjusting the heat supply to the heat demand of the heated object.

Extra energy is saved thanks to the continuous operation of the circulation pump.

Claims (4)

A method of regulating the heating water system, which measures outdoor air supply to the heating system 5 and adjusting the temperature of the return water from the heating system and adjusting the supply water temperature by adjusting the temperature dependence of the supply water temperature to the desired supply temperature 10 for each freely selected time interval, maintains the supply water temperature equal to this adjusted temperature value and switches on the circulation pump when the measured supply and return water temperatures exceed 15 required difference value calculated from the adjusted water supply temperature.