KR20030052608A - Plasma heat-exchanger and boiler using it - Google Patents

Abstract

PURPOSE: A plasma heat exchanger and a boiler using the plasma heat exchanger are provided to remove pollutants, to minimize the loss of superheat generated by the discharge of vacuum plasma, and to efficiently heat-exchange the superheat with water. CONSTITUTION: A plasma heat exchanger(100) is composed of a plasma chamber body(10), a high frequency power matching machine(20), a vacuum pump(30), a gas source, and a sequence controlling high frequency power supplier(50). The plasma chamber body comprises channels recessed to an outer peripheral surface of the chamber body to communicate with each other and closed by a channel cover(13), a plurality of heat absorbing projections(14) protruded at an inner peripheral surface of the chamber body, and a circular plate-shaped plasma curtain(15) shielding inner and outer spaces of the chamber body from plasma. The chamber body is laid with a pair of first and second radiators(11a,11b) mutually connected by a channel piping(16) and covered with heat insulating materials. The high frequency power matching machine inserted and arranged between the radiators and an outlet(23) of an inductive coil(21) is electrically coupled with an inlet(22) of the inductive coil, a spiral tube, communicated with a channel of the first radiator. The vacuum pump makes the inside of the chamber body vacuous through a vacuum piping having a vacuum valve(31) and a vacuum sensor(32). The gas source supplies gas for a plasma reaction to the chamber body through a gas piping having a gas valve(41). The sequence controlling high frequency power supplier controls the vacuum valve, the vacuum sensor, and the gas valve, supplies high frequency power from the power source through an input connector(24) to the high frequency power matching machine, and generates plasma inside the chamber body. Therefore, water of the channel heated by plasma reaction is circulated from the outlet of the chamber body to the inlet of the inductive coil.

Description

Plasma heat exchanger and boiler using same {PLASMA HEAT-EXCHANGER AND BOILER USING IT}

The present invention relates to a plasma heat exchanger for exchanging high heat generated during plasma discharge in water with water and a boiler using the same. In particular, the present invention not only controls the operation of the heat exchanger through a sequence-controlled high frequency power supply, In the configuration of the boiler using the heat exchanger according to the operation of the heat exchanger and the boiler can be harmonized by controlling various valves, temperature sensors, switches.

In general, conventional heat exchangers such as gas and oil boilers have been developed with an emphasis on how to effectively heat exchange the medium (heated in water) and the same medium circulated for hot water / heating and deprived of heat. However, since the conventional heat exchanger is based on the use of conventional fossil fuels, it is inevitably limited by fuel, and the pollutants are discharged by the use of fossil fuels, thereby preventing environmental pollution such as global warming. It is a cause of enormous foreign currency waste in Korea, which is caused by lack of underground resources.

In addition, in the field of heaters, heaters using thermal oils, which have recently been in the spotlight, aim to improve thermal efficiency, but have a problem in that the construction is complicated and the limitation of use due to the enlargement and the use of fossil fuels are also used.

Recently, the late night electricity is inexpensively supplied as a policy. However, the use of the late night electricity is not a breakthrough in terms of thermal efficiency since it does not escape the heat exchange structure of a conventional heating wire type.

Considering the power generation efficiency in addition to the midnight electricity, the development of a new concept heat exchanger and a boiler using the same is urgently required.

The present invention has been made to solve the problems posed in the conventional heat exchanger or heat exchange structure and the boiler using the same, the present invention is

Firstly, there is provided a plasma heat exchanger capable of efficiently exchanging heat with water while minimizing heat loss without high pollutant emission and vacuum plasma discharge,

Secondly, to provide various boilers using the plasma heat exchanger,

Third, an object of the present invention is to provide an apparatus and a system capable of efficiently performing operation control in the heat exchanger and a boiler using the same.

In order to achieve the above object, the plasma heat exchanger according to the present invention is formed in the outer circumferential surface of the chamber body so as to communicate with each other, and a water channel sealed by the water channel cover, a plurality of heat absorption protrusions protruding from the inner circumferential surface of the chamber body, and the inside and the outside of the chamber body from the plasma. A plasma chamber body including a plasma curtain on a circular plate that shields a space, the pair of first radiators and a second radiator connected to each other by a waterway pipe and wrapped in a heat insulating material; A high frequency power matcher inserted / arranged between the radiators and connected to an inlet of an induction coil which is a spiral tube whose outlet is in communication with a channel of the first radiator; A vacuum pump for evacuating the inside of the chamber body through a vacuum pipe and a vacuum sensor provided with a vacuum valve; A gas source for supplying a plasma reaction gas into the chamber body through a gas pipe provided with a gas valve; And a sequence controlled high frequency power supply controlling the vacuum valve, the vacuum sensor, and the gas valve, and supplying high frequency power from a power source to the high frequency power matcher through an input connector to generate plasma in the chamber body. And the heated water of the water passage is circulated from the outlet of the chamber body to the induction coil inlet by the plasma reaction.

In addition, the boiler using the plasma heat exchanger may be configured as a heating, hot water, heating / hot water combined as needed, the boiler according to the present invention according to the detection temperature in the temperature sensor mounted on the chamber body of the heat exchanger A boiler using water from a channel heated by a sequence-controlled high frequency power supply and heated to a set temperature, the inlet distributor being configured to receive water heated from an outlet of a heat exchanger formed in the chamber body through a pipe to an inlet; A hot water storage tank equipped with a temperature sensor and a water level switch to supply / store / supply hot water from the inlet distributor through a first hot water valve; A heating pipe equipped with a temperature sensor receiving the heating water from the inlet distributor through a first heating valve; Hot water from the hot water storage tank is passed through a second hot water valve, and the heating water from the heating pipe is circulated from the export port back to the induction coil inlet by the suction power of the circulation pump. Organically connect the necessary components in the circulation device consisting of an outlet distributor to form a hot water, heating or heating / hot water combined boiler, the temperature sensors, water level switch, valves and the circulation pump is the sequence control high frequency power supply To be controlled.

1 is a schematic diagram showing an example of a heating / hot water combined use boiler using a plasma heat exchanger according to the present invention,

2 is a schematic view showing the type of high frequency coil used in the plasma heat exchanger according to the present invention;

Figure 3 is a schematic diagram showing an example of configuring a heating dedicated boiler using a plasma heat exchanger according to the present invention,

4 is a schematic view showing an example of a boiler for hot water using the plasma heat exchanger according to the present invention.

Explanation of symbols on the main parts of the drawings

100: heat exchanger 10: chamber body

11a, 11b: first and second radiators 12: channel

13: channel cover 14: heat absorption protrusion

15: plasma curtain 16: channel piping

17: insulation 18: heat exchanger outlet

19: plasma discharge region

20: high frequency power matching device 21: induction coil

22: guide coil inlet 23: guide coil outlet

24: high frequency power input connector 25: high frequency insulator

30: vacuum pump 31: vacuum valve

32: vacuum sensor

41: gas valve 42: gas inlet

50: sequence control high frequency power supply

60: hot water storage tank 61: water level switch

62, 63: first and second hot water valve

70: import division 71: import branch

80: export division 81: export division

82: circulation pump

90: heating pipe 91,92: first, second heating valve

ST1, ST2, ST3: Temperature sensor 200: Heating / hot water circulation

300: heating circulation device 400: hot water circulation device

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. In the drawing --- ] Indicates the control relationship between the sequence control high frequency power supply and the components. ---- ▶] and [---- ▶] indicate the flow direction of water, gas and electricity. In addition, the [---- ▶] mark written together with the reference numerals is a mark for the reference numeral.

1 is a schematic view showing an example of a heating / hot water combined use boiler using a plasma heat exchanger according to the present invention. First, the heat exchanger 100 according to the present invention has a plasma chamber body 10 and an induction coil 21. A high frequency power matcher 20, a vacuum pump 30 for evacuating the chamber body 10, a gas source for supplying a plasma reaction gas into the chamber body 10, sequence control high frequency for controlling the components It consists of a power supply 50.

The plasma chamber body 10 is formed by combining the first and second radiators 11a and 11b. The outer circumferential surfaces of the radiators 11a and 11b are recessed so that the channels 12 communicate with each other, and the channels 12 are sealed by the channel covers 13. The size of the channel 12 varies according to the capacity of the plasma heat exchanger 100. The water channel cover 13 is coupled to cover the water channel 12 of the radiator so that water flows along the water channel and prevents water leakage. In particular, when the floats are attached and the heat exchange is not well performed, the water channel cover 13 is easy to clean. It is removable so that it is characterized. In addition, a plurality of heat absorbing protrusions 14 protrude from the inner circumferential surfaces of the radiators 11a and 11b. The upper and lower portions of the radiators are formed with a circular plate-shaped plasma curtain 15 that shields the inner and outer spaces of the chamber body 10 from the plasma. The plasma curtain 15 prevents the plasma heat generated at the center of the induction coil 21 from escaping to the outside of the radiators 11a and 11b to increase thermal efficiency. In addition, the plasma curtain 15 has a thickness of about 7 mm in order to efficiently transmit heat, and a circular hole of about 2 mm is formed in a circular center circumference thereof, and pipes are connected to the holes to form the plasma discharge region 19. It allows gas supply and vacuum exhaust in the inside, and helps to absorb heat by plasma. The radiators 11a and 11b of this structure are installed to form the chamber body 10, and the two channels 12 are connected to each other by the channel pipe 16. The channel pipe 16 is connected to the lower channel of the first radiator 11a to inject water warmed from the induction coil 21 and the first radiator 11a back into the second radiator 11b. Is further heated to the heat exchanger outlet 18.

This chamber body 10 may be hexahedral or cylindrical in shape, the outside of which is wrapped with a heat insulator 17. The thermal insulation material 17 is for preventing heat generated in the induction plasma heat exchanger 100 from being lost to the outside. Non-ferrous metals such as copper and aluminum having good thermal conductivity may be used as the materials of the first radiator 11a and the second radiator 11b.

The chamber body 10 including the radiators 11a and 11b has an induction coil 21 inserted / arranged through a hole formed in the upper plasma curtain and between the hole and the induction coil 21 for sealing the plasma. The high frequency insulator 25 is interposed. The high frequency insulator 25 surrounds the induction coil 21 in an airtight manner, and upper and lower edges of the high frequency insulator 25 are attached to the chamber body 10 and the curtain 15 to maintain a vacuum tightness. The plasma is prevented from being generated by the current flowing in the induction coil 21 from the outside of the body 10. The inlet 22 of the induction coil 21 exposed to the outside is electrically connected to the high frequency power matcher 20.

The induction coil 21 is a circular tube which is a kind of electricity flowing metal and is composed of an induction coil inlet 22 for injecting water and an induction coil outlet 23 for discharging water, and the induction coil outlet 23. ) Is electrically coupled to the center of the first radiator (11a) to become a common ground terminal of the high-frequency power supply and to flow the discharged water to the water channel (12). That is, water entering the inlet 22 of the induction coil 21 is introduced into the channel 12 of the first radiator 11a through the induction coil outlet 23. The shape of the induction coil 21 and the size of the tube vary according to the capacity of the induction plasma heat exchanger 100.

In addition, by inserting the induction coil 21 so that the plasma discharge region 19 is formed in the chamber body which is electromagnetically shielded and vacuum-tight, it uses heat absorbed by the induction coil itself and shields electromagnetic radiation to the outside. This eliminates the need for a separate electromagnetic shield. Two types of the induction coil 21 are schematically illustrated in FIG. 2, but similar results can be obtained using either 2-1 type or 2-1 type, but in a large induction plasma heat exchanger having a large capacity. Since a large area radiator should cover the plasma discharge area as a whole, a 2-1 type spiral is advantageous.

The high frequency power matcher 20 is composed of a tuning circuit in which two variable capacitors are connected in series or in parallel, and an output thereof is connected to an inlet 22 of the induction coil 21. It receives the high frequency power generated in the through the high frequency input connector 24 and consumes the high frequency power and transfers it to the induction coil 21 which is handled as a load without loss and is automatically controlled by the electronic circuit.

The vacuum pump 30 is for evacuating the interior of the chamber body 10 before the plasma discharge, and a vacuum valve 31 is installed on the pipe connected to the chamber body 10. The vacuum sensor 32 installed in the chamber body 10 senses the vacuum degree in the chamber body 10 and monitors whether the sensed vacuum degree is within a set range.

The gas source (not shown) is for supplying a gas for plasma reaction, and a gas valve 41 is installed on a pipe connected to the chamber body 10. Unexplained reference numeral 42 denotes a gas pipe inlet. As the gas for plasma reaction, an inert gas type such as argon, oxygen, or nitrogen is used.

The sequence control high frequency power supply 50 controls the vacuum valve 31 and the gas valve 41, and supplies the high frequency power from the power source to the high frequency power matcher 20 through the input connector 24. To generate a plasma in the chamber body (10).

The induction plasma heat exchanger 100 can be made in various sizes depending on the capacity.

The induction plasma heat exchanger 100 according to the present invention as described above may be used as a heating / hot water combination shown in FIG. 1, only the heating shown in FIG. 3, and the hot water shown in FIG. The capacity and the amount of high frequency energy supplied vary. In addition, the capacity of the induction plasma heat exchanger 100 varies depending on the size of the radiators 11a and 11b and the size of the induction coil 21, the amount of water passing through and the amount of water per unit time depending on the size. The time required to raise the temperature to the set temperature varies.

First, referring to the heating / hot water combined boiler shown in Figure 1, the heating / hot water combined boiler according to the detected temperature in the temperature sensor (ST1) mounted to the chamber body 10 in the plasma heat exchanger (100) The boiler is controlled by the sequence control high frequency power supply 50 and uses water from the channel 12 heated to a set temperature.

The import port distributor 70 receives the heated water from the heat exchanger outlet 18 formed in the chamber body 10 to the import port 71 through a pipe. The hot water from the inlet distributor 70 is supplied to the hot water storage tank 60 equipped with the temperature sensor ST2 and the water level switch 61 via the first hot water valve 62 to be used for hot water. In addition, the heating water from the inlet distributor 70 is supplied to the heating pipe 90 equipped with the temperature sensor ST3 via the first heating valve 91 and used for heating. Water used for hot water or heating first passes through a second hot water valve 63 from the hot water storage tank 60 in the case of hot water, and then second heating from the heating pipe 90 in the case of heating water. The water circulation system 200 made up of the outlet distributor 80 is configured to circulate from the outlet 81 back to the induction coil inlet 22 by the suction force of the circulation pump 82 via the valve 92. Configuration. The temperature sensor ST2 (ST3), the water level switch 61, the valves 62, 63, 91, 92, and the circulation pump 82 are controlled by the sequence control high frequency power supply 50. do.

In the case of the heating-only boiler shown in FIG. 3, the heat exchanger is the same as the heating / hot water boiler shown in FIG. 1, and in the circulation device 300, there is no configuration of the hot water storage tank 60 for hot water use. Instead, a water supplement 60a for replenishing water consumed by evaporation or the like is provided. In addition, valves 91 and 92 are not needed in FIG.

In the case of the hot water-only boiler shown in FIG. 4, the heat exchanger is also the same as the heating / hot water boiler shown in FIG. 1, and there is no configuration of the heating pipe 90 for heating use in the circulation device 400. .

Plasma heat exchanger 100 of the present invention described above was mainly focused on heat exchange with water, but by modifying the channel portion 12 of the radiators 11a and 11b to make a heat sink and blowing it between the heat sinks with a fan as a plasma warmer. It can be used without any problems.

Hereinafter, with reference to the accompanying drawings will be described the operation of the plasma heat exchanger and the boiler using the same according to the present invention.

The plasma generation gas is supplied from the gas supply source into the vacuum chamber body 10 evacuated using the vacuum pump 30 to obtain a gas partial pressure, and the high frequency power is controlled by the sequence control high frequency power supply 50. When supplied through the matcher 20, the strong plasma region 19 is symmetrically generated about the induction coil 21 by the alternating magnetic field of the induction coil 21, thereby generating high temperature plasma heat.

The generated plasma heat is absorbed by the heat absorbing protrusions 14 of the first and second radiators 11a and 11b and the induction coil 21 itself so that the channels 12 of the radiators 11a and 11b are absorbed. ) And the temperature of the water flowing in the induction coil 21 is quickly increased.

The water heated by the plasma heat is discharged to the heat exchanger outlet 18 of the induction plasma heat exchanger 100 to the inlet distributor 70 through the inlet 71 of the circulators 200, 300, and 400. Enter

In the case of a combined heating / hot water boiler using the circulation device 200 of FIG. 1 or a hot water boiler of FIG. 4, hot water supply to the hot water storage tank 60 is performed by a key input to the sequence control high frequency power supply 50. When the temperature sensed by the temperature sensor ST2 installed in the hot water storage tank 60 becomes lower than the set value in the state of selecting and setting the temperature of the hot water temperature, the first hot water valve installed in the inlet distributor 70 ( 62) and the induction plasma heat exchanger 100 in which the second hot water valve 63 installed in the outlet distributor 80 is opened and plasma is generated from the hot water storage tank 60 by the circulation pump 82. After circulating to the induction coil inlet 22 to raise the set value temperature, the high-frequency energy supplied to the induction plasma heat exchanger 100 is cut off, and the first hot water valve 62 and the second hot water valve ( 63) Close.

Meanwhile, in the case of the heating / hot water boiler of FIG. 1 or the heating-only boiler of FIG. 3, in order to send the heating water to the heating pipe 90, heating is selected and input by a key input to the sequence control high frequency power supply 50. In the state where the set value of the temperature is specified, if the temperature sensed by the temperature sensor ST3 installed in the heating pipe 90 is lower than the set value, the first heating valve 91 and the number installed in the inlet distributor 70 The second heating valve 2 installed in the outlet distributor 80 is opened and the water of the heating pipe 90 is circulated to the induction coil inlet 22 of the induction plasma heat exchanger 100 by the circulation pump 82. After that, the temperature is raised to the set temperature, and then the high frequency power of the sequence control high frequency power supply 50 is intermittently supplied to the induction plasma heat exchanger 100 to automatically adjust to fall within the deviation of the heating set temperature value.

Particularly, when the hot water selection and the heating selection are simultaneously selected by key input to the sequence control high frequency power supply 50 in the heating / hot water combined boiler shown in FIG. 1, heating is preferentially selected so that the heating temperature is set to a set value. The above operation is performed to increase the temperature of the water in the hot water storage tank 60 at the remaining time. That is, when the temperature sensed by the heating temperature sensor ST3 falls below a set value deviation, heating is selected even though the temperature of the water in the hot water storage tank 60 does not reach the set value, thereby providing hot water to the heating pipe 90. Supply.

The water level switch 61 detects the water level in the hot water storage tank 60. There are two types of the high water level switch and the low water level switch. ) Will be adjusted automatically.

Referring to the experimental conditions of the induction plasma heat exchanger 100 as follows. Argon gas is injected into the chamber body 10 evacuated by the vacuum pump 30 through the gas inlet 5 to adjust the vacuum degree in the vacuum chamber 10 to be 0.1 Torr to 1 Torr, and the frequency is 13.56 [. MHz] or 27.12 [MHz] is supplied to the induction plasma heat exchanger 100 from 50 [W] to 2000 [[W] depending on the capacity of the induction plasma heat exchanger 100 and the heating pipe 90 The temperature sensor (ST3) and the temperature sensor (ST2) installed in the hot water storage tank (30) to detect the actual temperature of the heating and hot water, compare it with the temperature set value and if the actual temperature is high cut off the high frequency energy and low In this case, proportional time control is executed by intermittent supply. The vacuum degree in the vacuum chamber 10 is appropriately 0.2 Torr to 0.5 Torr in consideration of the efficiency of the induction plasma heat exchanger 100, and the magnitude of the high frequency energy is independent of the capacity of the induction plasma heat exchanger 100. It should be more than 50 [W] to efficiently obtain plasma thermal energy. In addition, in order to maximize the efficiency of the high frequency energy supplied to the high frequency generator and the efficiency of the induction plasma heat exchanger 100, the size of the output is fixed to the maximum output.

As an effect of the plasma heat exchanger and the boiler using the same according to the present invention,

First, since the heat exchanger according to the present invention is heat exchanged using the plasma, there is no emission of pollutants, and the high heat generated by the vacuum plasma discharge through the chamber body in the form of one body and the water flowing in the channel while minimizing the heat loss. Can exchange heat efficiently

Second, not only can provide a hot water / heating / heating / hot water combined boiler using the plasma heat exchanger, can also be applied to a hot air fan by modifying the heat exchanger,

Third, it is a very advanced invention that can efficiently perform operation control by systemizing a heat exchanger and a boiler using the same through a sequence control high frequency power supply that controls various temperature sensors, vacuum sensors, valves, and components.

Claims (4)

The channel 12 is formed in the outer peripheral surface of the chamber body 10 so as to communicate with each other, the channel 12 sealed by the channel cover 13, the plurality of heat absorbing protrusions 14 protruding from the inner peripheral surface of the chamber body 10, and the chamber from the plasma. Including a circular plate-shaped plasma curtain 15 to shield the inner and outer space of the body, a pair of first radiator (11a) and the second radiator (11b) connected to each other by the water pipe 16 is installed to the heat insulating material ( A plasma chamber body 10 enclosed in 17); An inlet 22 of the induction coil 21 which is a spiral tube inserted / arranged between the radiators 11a and 11b and whose outlet 23 is in communication with the channel 12 of the first radiator 11a. An electrically connected high frequency power matcher 20; A vacuum pump (30) for evacuating the inside of the chamber body (10) through a vacuum pipe and a vacuum pipe (32) provided with a vacuum valve (31); A gas source for supplying a plasma reaction gas into the chamber body 10 through a gas pipe in which a gas valve 41 is installed; And The chamber body is controlled by controlling the vacuum valve 31, the vacuum sensor 32, and the gas valve 41, and supplying high frequency power from a power source to the high frequency power matcher 20 through an input connector 24. And a sequence controlled high frequency power supply (50) which generates a plasma within (10). The heated water of the channel (12) is induced by the plasma reaction from the outlet (18) of the chamber body (10). A plasma heat exchanger (100) adapted to be circulated through a coil inlet (22). The plasma heat exchanger (100) according to claim 1 is controlled by the sequence control high frequency power supply (50) according to the detection temperature of the temperature sensor (ST1) mounted to the chamber body (10) and heated to a set temperature. As a boiler using water from the channel 12, An inlet outlet distributor 70 receiving water heated from the heat exchanger outlet 18 formed in the chamber body 10 to an inlet port 71 through a pipe; A hot water storage tank (60) equipped with a temperature sensor (ST2) and a water level switch (61) for supplying / storing / supplying hot water from the inlet distributor (70) via a first hot water valve (62); A heating pipe (90) equipped with a temperature sensor (ST3) for receiving the heating water from the inlet distributor (70) via a first heating valve (91); Hot water from the hot water storage tank 60 passes through the second hot water valve 63 and the heating water from the heating pipe 90 passes through the second heating valve 92 to the suction power of the circulation pump 82. By the water outlet circulator 200 consisting of an outlet distributor 80 is circulated from the export port 81 to the induction coil inlet 22 again, the temperature sensor (ST2) (ST3), the water level switch (61), valves (62, 63) (91) (92), and circulating pump (82) are to be controlled by the sequence controlled high frequency power supply (50). The plasma heat exchanger (100) according to claim 1 is controlled by the sequence control high frequency power supply (50) according to the detection temperature of the temperature sensor (ST1) mounted to the chamber body (10) and heated to a set temperature. As a boiler using water from the channel 12, An inlet outlet distributor 70 receiving water heated from the heat exchanger outlet 18 formed in the chamber body 10 to an inlet port 71 through a pipe; A heating pipe (90) equipped with a temperature sensor (ST3) for receiving the heating water from the import port distributor (70); Heating consisting of an export distributor (80) configured to circulate the heating water from the heating pipe (90) from the export outlet (81) back to the induction coil inlet (22) by the suction force of the circulation pump (82). The water circulation device 300, wherein the temperature sensor (ST3) and the circulation pump 82 is to be controlled by the sequence control high frequency power supply (50). The plasma heat exchanger (100) according to claim 1 is controlled by the sequence control high frequency power supply (50) according to the detection temperature of the temperature sensor (ST1) mounted to the chamber body (10) and heated to a set temperature. As a boiler using water from the channel 12, An inlet outlet distributor 70 receiving water heated from the heat exchanger outlet 18 formed in the chamber body 10 to an inlet port 71 through a pipe; A hot water storage tank (60) equipped with a temperature sensor (ST2) and a water level switch (61) for supplying / storing / supplying hot water from the inlet distributor (70) via a first hot water valve (62); The hot water from the hot water storage tank 60 may be circulated from the export port 81 to the induction coil inlet 22 by the suction force of the circulation pump 82 via the second hot water valve 63. The outlet distributor 80 is a hot water circulation device 400, the temperature sensor (ST2), the water level switch 61, the valves (62, 63) and the circulation pump 82 is the sequence control high frequency power supply ( Hot water boiler which is supposed to be controlled by 50).