Column flow vpg 23 frog design. Gas instantaneous water heaters
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Instantaneous water heater VPG-23
1. Unconventional look on ecological and economiccal problems of the gas industry
It is known that Russia is the richest country in the world in terms of gas reserves.
From an environmental point of view, natural gas is the cleanest type of mineral fuel. When burned, it produces a significantly smaller amount of harmful substances compared to other types of fuel.
However, the burning of a huge amount of various kinds fuel, including natural gas, over the past 40 years has led to a marked increase in carbon dioxide in the atmosphere, which, like methane, is a greenhouse gas. Most scientists consider this circumstance to be the cause of the currently observed climate warming.
This problem alarmed public circles and many statesmen after the publication in Copenhagen of the book "Our Common Future", prepared by the UN Commission. It reported that climate warming could cause the melting of ice in the Arctic and Antarctica, which would lead to a rise in the level of the World Ocean by several meters, flooding of island states and the invariable coasts of the continents, which would be accompanied by economic and social upheavals. To avoid them, it is necessary to sharply reduce the use of all hydrocarbon fuels, including natural gas. International conferences were convened on this issue, intergovernmental agreements were adopted. Atomic scientists of all countries began to extol the virtues of atomic energy, which is detrimental to mankind, the use of which is not accompanied by the release of carbon dioxide.
Meanwhile, the alarm was in vain. The erroneousness of many forecasts given in the mentioned book is connected with the absence of natural scientists in the UN Commission.
However, the issue of sea level rise has been carefully studied and discussed at many international conferences. It revealed. That in connection with the warming of the climate and the melting of ice, this level is really rising, but at a rate not exceeding 0.8 mm per year. In December 1997, at a conference in Kyoto, this figure was refined and turned out to be 0.6 mm. This means that in 10 years the ocean level will rise by 6 mm, and in a century by 6 cm. Of course, this figure should scare no one.
In addition, it turned out that the vertical tectonic movement of coastlines exceeds this value by an order of magnitude and reaches one, and in some places even two centimeters per year. Therefore, despite the rise in the 2nd level of the World Ocean, the Sea in many places becomes shallow and recedes (the north of the Baltic Sea, the coast of Alaska and Canada, the coast of Chile).
Meanwhile, global warming may have a number of positive consequences, especially for Russia. First of all, this process will increase the evaporation of water from the surface of the seas and oceans, whose area is 320 million km2. 2 The climate will become more humid. The droughts in the Lower Volga region and in the Caucasus will be reduced and may be stopped. The border of agriculture will begin to slowly move northward. Navigation along the Northern Sea Route will be greatly facilitated.
Reduce winter heating costs.
Finally, it must be remembered that carbon dioxide is food for all terrestrial plants. It is by processing it and releasing oxygen that they create primary organic matter. Back in 1927, V.I. Vernadsky pointed out that green plants could process and convert into organic substances much more carbon dioxide than its modern atmosphere can give. Therefore, he recommended the use of carbon dioxide as a fertilizer.
Subsequent experiments in phytotrons confirmed V.I. Vernadsky. When grown under conditions of twice the amount of carbon dioxide, almost all cultivated plants grew faster, fruited 6-8 days earlier and yielded 20-30% more than in control experiments with its usual content.
Consequently, agriculture is interested in enriching the atmosphere with carbon dioxide by burning hydrocarbon fuels.
An increase in its content in the atmosphere is also useful for more southern countries. Judging by paleographic data, 6-8 thousand years ago during the so-called Holocene climatic optimum, when the average annual temperature at the latitude of Moscow was 2C higher than the present one in Central Asia, there was a lot of water and no deserts. Zeravshan flowed into the Amu Darya, r. The Chu flowed into the Syr Darya, the level of the Aral Sea stood at +72 m, and the connected Central Asian rivers flowed through present-day Turkmenistan into the sagging depression of the South Caspian. The sands of Kyzylkum and Karakum are river alluvium of the recent past, scattered later.
And the Sahara, whose area is 6 million km 2, was also not a desert at that time, but a savannah with numerous herds of herbivores, full-flowing rivers and Neolithic human settlements on the banks.
Thus, the combustion of natural gas is not only economically 3 profitable, but also quite justified from an environmental point of view, since it contributes to climate warming and humidification. Another question arises: should we conserve and save natural gas for our descendants? For a correct answer to this question, it should be taken into account that scientists are on the verge of mastering the energy of nuclear fusion, which is even more powerful than the energy of nuclear decay used, but does not produce radioactive waste and therefore, in principle, is more acceptable. According to American magazines, this will happen already in the first years of the coming millennium.
Probably regarding such short terms they are wrong. Nevertheless, the possibility of the emergence of such an alternative environmentally friendly type of energy in the near future is obvious, which cannot be ignored when developing a long-term concept for the development of the gas industry.
Techniques and methods of ecological-hydrogeological and hydrological studies of natural-technogenic systems in the areas of gas and gas condensate fields.
In ecological, hydrogeological and hydrological studies, it is urgent to solve the issue of finding effective and economical methods for studying the state and predicting technogenic processes in order to: develop a strategic concept for production management that ensures the normal state of ecosystems develop tactics for solving the complex engineering tasks contributing rational use deposit resources; implementation of a flexible and efficient environmental policy.
Ecological-hydrogeological and hydrological studies are based on monitoring data, which has been developed to date from the main fundamental positions. However, the task of continuous optimization of monitoring remains. The most vulnerable part of monitoring is its analytical and instrumental base. In this connection, it is necessary: unification of analysis methods and modern laboratory equipment, which would allow economically, quickly, with great accuracy to perform analytical work; creation of a single document for the gas industry that regulates the entire range of analytical work.
The methodological methods of ecological, hydrogeological and hydrological research in the areas of the gas industry are overwhelmingly common, which is determined by the uniformity of the sources of anthropogenic impact, the composition of the components that experience anthropogenic impact, and 4 indicators of anthropogenic impact.
The peculiarities of the natural conditions of the territories of fields, for example, landscape-climatic (arid, humid, etc., shelf, continent, etc.), determine the differences in character, and if the character is the same, in the degree of intensity of the technogenic impact of gas industry facilities on natural environments . Thus, in fresh groundwater in humid areas, the concentration of pollutant components coming with industrial waste often increases. In arid areas, due to the dilution of mineralized (typical of these areas) groundwater with fresh or low-mineralized industrial effluents, the concentration of pollutant components in them decreases.
Particular attention to groundwater when considering environmental problems follows from the concept of groundwater as a geological body, namely, groundwater is a natural system that characterizes the unity and interdependence of chemical and dynamic properties determined by the geochemical and structural features of groundwater, containing (rocks) and surrounding ( atmosphere, biosphere, etc.) environments.
Hence the multifaceted complexity of ecological and hydrogeological studies, which consists in the simultaneous study of the technogenic impact on groundwater, the atmosphere, the surface hydrosphere, the lithosphere (rocks of the aeration zone and water-bearing rocks), soils, the biosphere, in determining the hydrogeochemical, hydrogeodynamic and thermodynamic indicators of technogenic changes, in the study mineral organic and organic components of the hydrosphere and lithosphere, in the application of natural and experimental methods.
Both surface (mining, processing and related facilities) and underground (deposits, production and injection wells) sources of technogenic impact are subject to study.
Ecological-hydrogeological and hydrological studies make it possible to detect and evaluate almost all possible technogenic changes in natural and natural-technogenic environments in the areas where gas industry enterprises operate. For this, a serious knowledge base about the geological-hydrogeological and landscape-climatic conditions prevailing in these territories, and a theoretical justification for the spread of technogenic processes, are mandatory.
Any technogenic impact on the environment is assessed against the background of the environment. It is necessary to distinguish between the background natural, natural-technogenic, technogenic. The natural background for any indicator under consideration is represented by a value (values) formed in natural conditions, natural and technogenic - in 5 conditions experiencing (experienced) technogenic loads from outsiders, not monitored in this particular case, objects, technogenic - under the influence of side of the monitored (studied) man-made object in this particular case. The technogenic background is used for a comparative spatio-temporal assessment of changes in the steppe of the technogenic impact on the Environment during the periods of operation of the monitored object. This is an obligatory part of monitoring, providing flexibility in the management of technogenic processes and timely implementation of environmental measures.
With the help of natural and natural-technogenic background, an anomalous state of the studied media is detected and areas characterized by its different intensity are established. The anomalous state is fixed by the excess of the actual (measured) values and the studied indicator over its background values (Cact>Cbackground).
A technogenic object that causes the occurrence of technogenic anomalies is established by comparing the actual values of the studied indicator with the values in the sources of technogenic influence belonging to the monitored object.
2. EcologicalOther benefits of natural gas
There are issues related to the environment that have prompted much research and discussion on an international scale: issues of population growth, conservation of resources, biodiversity, climate change. The last question is most directly related to the energy sector of the 1990s.
The need for detailed study and policy development on an international scale led to the creation of the Intergovernmental Panel on Climate Change (IPCC) and the conclusion of the Framework Convention on Climate Change (FCCC) through the UN. Currently, the UNFCCC has been ratified by more than 130 countries that have acceded to the Convention. The first Conference of the Parties (COP-1) was held in Berlin in 1995, and the second (COP-2) was held in Geneva in 1996. COP-2 approved the IPCC report, which stated that there was already real evidence that that human activity is responsible for climate change and the effect of "global warming".
Although there are opinions that oppose that of the IPCC, such as those of the European Science and Environment Forum, the work of the IPCC in 6 is now accepted as an authoritative basis for policy makers and it is unlikely that the impetus given by the UNFCCC will not encourage further development . Gases. most important, i.e. those whose concentrations have increased significantly since the start of industrial activity are carbon dioxide (CO2), methane (CH4) and nitric oxide (N2O). In addition, although their levels in the atmosphere are still low, the continuing increase in the concentrations of perfluorocarbons and sulfur hexafluoride makes it necessary to touch them too. All of these gases should be included in national inventories submitted under the UNFCCC.
The effect of increasing gas concentrations, which causes the greenhouse effect in the atmosphere, was modeled by the IPCC under various scenarios. These modeling studies have shown systematic global climate change since the 19th century. IPCC is waiting. that between 1990 and 2100 the average air temperature on the earth's surface will increase by 1.0-3.5 C. and the sea level will rise by 15-95 cm. More severe droughts and / or floods are expected in some places, while how they will be less severe elsewhere. Forests are expected to die, which will further change the sequestration and release of carbon on land.
The expected temperature change will be too fast for individual animal and plant species to adjust. and some decline in biodiversity is expected.
Sources of carbon dioxide can be quantified with reasonable certainty. One of the most significant sources of increasing CO2 concentration in the atmosphere is the combustion of fossil fuels.
Natural gas produces less CO2 per unit of energy. supplied to the consumer. than other fossil fuels. In comparison, methane sources are more difficult to quantify.
Globally, fossil fuel sources are estimated to contribute about 27% of annual anthropogenic methane emissions to the atmosphere (19% of total emissions, anthropogenic and natural). The uncertainty intervals for these other sources are very large. For example. emissions from landfills are currently estimated at 10% of anthropogenic emissions, but they could be twice as high.
The global gas industry has been studying the development of scientific understanding of climate change and related policies for many years, and has engaged in discussions with renowned scientists working in the field. The International Gas Union, Eurogas, national organizations and individual companies participated in the collection of relevant data and information and thus contributed to these discussions. While there are still many uncertainties about accurately assessing the potential future impact of greenhouse gases, it is appropriate to apply the precautionary principle and ensure that cost-effective emission reduction measures are implemented as soon as possible. For example, emission inventories and mitigation technology discussions have helped focus attention on the most appropriate measures to control and reduce greenhouse gas emissions under the UNFCCC. Go to industrial types Fuels with a lower carbon yield, such as natural gas, can reduce greenhouse gas emissions at a reasonable cost-effectiveness, and such transitions are taking place in many regions.
The exploration of natural gas instead of other fossil fuels is economically attractive and can make an important contribution to meeting the commitments made by individual countries under the UNFCCC. It is a fuel that has minimal environmental impact compared to other fossil fuels. Switching from fossil coal to natural gas, while maintaining the same ratio of fuel-to-electricity conversion efficiency, would reduce emissions by 40%. In 1994
The IGU Special Commission on the Environment, in a report at the World Gas Conference (1994), turned to the study of climate change and showed that natural gas can make a significant contribution to reducing greenhouse gas emissions associated with energy supply and energy consumption, providing the same level of convenience, performance and reliability that will be required from the energy supply in the future. The Eurogas brochure "Natural Gas - Cleaner Energy for a Cleaner Europe" demonstrates the protection benefits of using natural gas environment, when considering issues from local to 8 global levels.
Although natural gas has advantages, it is still important to optimize its use. The gas industry has supported technology improvement efficiency programs complemented by the development of environmental management, further strengthening the environmental case for gas as an efficient fuel that contributes to environmental protection in the future.
Carbon dioxide emissions worldwide are responsible for about 65% of global warming. the globe. Burning fossil fuels releases CO2 accumulated by plants many millions of years ago and increases its concentration in the atmosphere above natural levels.
The burning of fossil fuels is responsible for 75-90% of all anthropogenic carbon dioxide emissions. Based on the most recent data provided by the IPCC, the relative contribution of anthropogenic emissions to the amplification of the greenhouse effect is estimated by the data.
Natural gas generates less CO2 for the same supply of energy than coal or oil because it contains more hydrogen to carbon than other fuels. Due to its chemical structure, the gas produces 40% less carbon dioxide than anthracite.
Emissions to the atmosphere from the combustion of fossil fuels depend not only on the type of fuel, but on how efficiently it is used. Gaseous fuels typically burn more easily and more efficiently than coal or oil. Waste heat recovery from flue gases is also easier in the case of natural gas, since the flue gas is not contaminated with solid particles or aggressive sulfur compounds. Thanks to chemical composition ease and efficiency of use, natural gas can make a significant contribution to reducing carbon dioxide emissions by replacing fossil fuels.
3. Water heater VPG-23-1-3-P
gas appliance thermal water supply
Gas appliance using thermal energy, obtained by burning gas, for heating running water for hot water supply.
Deciphering the instantaneous water heater VPG 23-1-3-P: VPG-23 V-water heater P - flow G - gas 23 - thermal power 23000 kcal/h. At the beginning of the 70s, the domestic industry mastered the production of unified flow-through water heating household appliances who received the HSV index. Currently, water heaters of this series are produced by gas equipment factories located in St. Petersburg, Volgograd and Lvov. These devices belong to automatic devices and are designed to heat water for the needs of local household supply of the population and household consumers. hot water. Water heaters are adapted for successful operation in conditions of simultaneous multi-point water intake.
A number of significant changes and additions have been made to the design of the instantaneous water heater VPG-23-1-3-P in comparison with the previously produced water heater L-3, which, on the one hand, improved the reliability of the device and ensured an increase in the level of safety of its operation, in in particular, to resolve the issue of turning off the gas supply to the main burner in case of violations of draft in the chimney, etc. but, on the other hand, led to a decrease in the reliability of the water heater as a whole and the complication of the process of its maintenance.
The body of the water heater has acquired a rectangular, not very elegant shape. The design of the heat exchanger has been improved, the main burner of the water heater has been radically changed, respectively - the ignition burner.
A new element has been introduced, which was not previously used in instantaneous water heaters - solenoid valve(EMK); a draft sensor is installed under the gas outlet device (hood).
As the most common means for quick receipt hot water in the presence of water supply, for many years, gas flow-through water heaters manufactured in accordance with the requirements are used, equipped with gas exhaust devices and draft breakers, which, in the event of a short-term violation of draft, prevent the flame of the gas burner from extinguishing, there is a smoke exhaust pipe for connection to the smoke channel.
Device device
1. The wall-mounted apparatus has a rectangular shape formed by a removable lining.
2. All main elements are mounted on the frame.
3. On the front side of the apparatus there is a gas cock control knob, a solenoid valve switch button (EMC), a viewing window, a window for ignition and monitoring the flame of the pilot and main burners, and a draft control window.
· At the top of the device there is a branch pipe for the removal of combustion products into the chimney. Below - branch pipes for connecting the device to the gas and water mains: For gas supply; For supply cold water; For hot water.
4. The device consists of a combustion chamber, which includes a frame, a gas exhaust device, a heat exchanger, a water-gas burner unit, consisting of two burners, an ignition and a main burner, a tee, gas cock, 12 water regulators, solenoid valve (EMC).
On the left side of the gas part of the water and gas burner block, a tee is attached using a clamping nut, through which gas enters the pilot burner and, in addition, is supplied through a special connecting pipe under the draft sensor valve; that, in turn, is attached to the body of the apparatus under the gas outlet device (cap). The draft sensor is an elementary design, it consists of a bimetallic plate and a fitting on which two nuts are mounted that perform connecting functions, and the upper nut is also a seat for a small valve attached in a suspended state to the end of the bimetallic plate.
The minimum thrust required for the normal operation of the apparatus should be 0.2 mm of water. Art. If the draft has fallen below the specified limit, the exhaust products of combustion, which are not able to completely escape into the atmosphere through the chimney, begin to enter the kitchen, heating the bimetallic plate of the draft sensor, located in a narrow passage on their way out from under the hood. When heated, the bimetallic plate gradually bends, since the coefficient of linear expansion during heating at the lower metal layer is greater than that of the upper one, its free end rises, the valve moves away from the seat, which entails depressurization of the tube connecting the tee and the thrust sensor. Due to the fact that the gas supply to the tee is limited by the flow area in the gas part of the water-gas burner unit, which occupies much less than the area of the thrust sensor valve seat, the gas pressure in it immediately drops. The igniter flame, not receiving sufficient power, falls off. The cooling of the thermocouple junction causes the solenoid valve to actuate after a maximum of 60 seconds. The electromagnet, left without electric current, loses its magnetic properties and releases the armature of the upper valve, not having the strength to keep it in a position attracted to the core. Under the influence of a spring, a plate equipped with a rubber seal fits snugly against the seat, while blocking the through passage for the gas that previously entered the main and pilot burners.
Rules for using instantaneous water heater.
1) Before turning on the water heater, make sure that there is no smell of gas, slightly open the window and release the undercut at the bottom of the door for air flow.
2) The flame of a lit match check the draft in the chimney, if there is draft, turn on the column according to the instruction manual.
3) 3-5 minutes after turning on the device re-check for traction.
4) Don't allow use the water heater for children under 14 years of age and persons who have not received special instructions.
Use gas water heaters only if there is draft in the chimney and ventilation duct Rules for storing instantaneous water heaters. Flowing gas water heaters must be stored indoors, protected from atmospheric and other harmful influences.
When storing the apparatus for more than 12 months, the latter must be subjected to conservation.
The openings of the inlet and outlet pipes must be closed with plugs or plugs.
Every 6 months of storage, the device must be subjected to a technical inspection.
How the machine works
b Switching on the apparatus 14 To switch on the apparatus, it is necessary to: Check the presence of draft by bringing a lighted match or a strip of paper to the draft control window; Open the common valve on the gas pipeline in front of the apparatus; Open the faucet water pipe in front of the device Turn the gas cock handle clockwise until it stops; Press the button of the solenoid valve and bring a lit match through the viewing window in the lining of the apparatus. In this case, the flame of the pilot burner should light up; Release the button of the solenoid valve, after turning it on (after 10-60 seconds), while the flame of the pilot burner should not go out; Open the gas cock to the main burner by pressing the gas cock handle in the axial direction and turning it to the right as far as it will go.
b At the same time, the pilot burner continues to burn, but the main burner does not yet ignite; Open the hot water valve, the flame of the main burner should flash. The degree of water heating is adjusted by the amount of water flow, or by turning the gas valve handle from left to right from 1 to 3 divisions.
b Turn off the machine. At the end of using the instantaneous water heater, it must be turned off, following the sequence of operations: Close the hot water taps; Turn the gas valve handle counterclockwise until it stops, thereby shutting off the gas supply to the main burner, then release the knob and without pressing it in the axial direction, turn it counterclockwise until it stops. This will turn off the ignition burner and the electromagnetic valve (EMC); Close the general valve on the gas pipeline; Close the valve on the water pipe.
b The water heater consists of the following parts: Combustion chamber; Heat exchanger; frame; gas outlet device; Gas burner block; Main burner; Ignition burner; Tee; Gas cock; Water regulator; Solenoid valve (EMC); Thermocouple; Thrust sensor tube.
Solenoid valve
In theory, the solenoid valve (EMC) should stop the gas supply to the main burner of the instantaneous water heater: firstly, when the gas supply to the apartment (to the water heater) disappears, in order to avoid the gas contamination of the fire chamber, connecting pipes and chimneys, and secondly, in case of violation of draft in the chimney (reducing it against the established norm), in order to prevent poisoning carbon monoxide contained in the products of combustion, the residents of the apartment. The first of the functions mentioned in the design of previous models of instantaneous water heaters was assigned to the so-called thermal machines, which were based on bimetallic plates and valves suspended from them. The design was quite simple and cheap. After a certain time, it failed after a year or two, and not a single locksmith or production manager even thought about the need to waste time and material on restoration. Moreover, experienced and knowledgeable locksmiths at the time of starting the water heater and its initial testing, or at the latest at the first visit (preventive maintenance) of the apartment, in full consciousness of their rightness, pressed the fold of the bimetallic plate with pliers, thereby ensuring a constant open position for the thermal machine valve, and also a 100% guarantee that the specified safety automation element will not disturb either subscribers or maintenance personnel until the expiration date of the water heater.
However, in the new model of the instantaneous water heater, namely HSV-23-1-3-P, the idea of a "thermal automatic" was developed and significantly complicated, and, worst of all, connected to a traction control automatic, assigning the functions of a thrust guard to the solenoid valve , functions that are certainly necessary, but so far have not received a worthy embodiment in a specific viable design. The hybrid turned out to be not very successful, capricious in work, requiring increased attention from the attendants, high qualifications and many other circumstances.
The heat exchanger, or radiator, as it is sometimes called in the practice of gas facilities, consists of two main parts: a fire chamber and a heater.
The fire chamber is designed to burn the gas-air mixture, almost entirely prepared in the burner; secondary air, which ensures complete combustion of the mixture, is sucked in from below, between the burner sections. The cold water pipeline (coil) wraps around the fire chamber with one full turn and immediately enters the heater. The dimensions of the heat exchanger, mm: height - 225, width - 270 (including protruding knees) and depth - 176. The diameter of the coil tube is 16 - 18 mm, it is not included in the above depth parameter (176 mm). The heat exchanger is single-row, has four through circulation passes of the water-carrying tube and about 60 plates-ribs made of copper sheet and having a wavy side profile. For installation and alignment inside the water heater body, the heat exchanger has side and rear brackets. The main type of solder on which the PFOTS-7-3-2 coil elbows are assembled. It is also possible to replace solder with MF-1 alloy.
In the process of checking the tightness of the internal water plane, the heat exchanger must withstand a pressure test of 9 kgf / cm 2 for 2 minutes (water leakage from it is not allowed) or subjected to an air test for a pressure of 1.5 kgf / cm 2, provided that it is immersed in a bath filled with water, also within 2 minutes, and air leakage (the appearance of bubbles in the water) is not allowed. Elimination of defects in the water path of the heat exchanger by tapping is not allowed. Almost the entire length of the cold water coil on the way to the heater must be tacked to the fire chamber with solder to ensure maximum water heating efficiency. At the outlet of the heater, the exhaust gases enter the gas exhaust device (hood) of the water heater, where it is diluted with air drawn in from the room to the required temperature and then goes into the chimney through a connecting pipe, the outer diameter of which should be approximately 138 - 140 mm. The temperature of the flue gases at the outlet of the gas outlet is approximately 210 0 С; the content of carbon monoxide at an air flow rate equal to 1 should not exceed 0.1%.
The principle of operation of the device 1. The gas through the tube enters the electromagnetic valve (EMC), the switch button of which is located to the right of the gas cock switch handle.
2. The gas shut-off valve of the water and gas burner unit sequences the firing of the pilot burner, supplying gas to the main burner, and adjusting the amount of gas supplied to the main burner to obtain the desired temperature of the heated water.
The gas cock has a handle that rotates from left to right with a lock in three positions: The leftmost fixed position corresponds to closing 18 of the gas supply to the pilot and main burners.
The middle fixed position corresponds to the full opening of the valve for gas supply to the pilot burner and the closed position of the valve to the main burner.
The rightmost fixed position, achieved by pressing the handle in the main direction until it stops, followed by turning it all the way to the right, corresponds to the full opening of the valve for gas supply to the main and pilot burners.
3. Regulation of combustion of the main burner is carried out by turning the knob within position 2-3. In addition to manual blocking of the crane, there are two automatic blocking devices. Blocking the flow of gas to the main burner during the mandatory operation of the pilot burner is provided by a solenoid valve operating from a thermocouple.
Blocking the gas supply to the burner, depending on the presence of water flow through the device, is carried out by the water regulator.
When the solenoid valve (EMC) button is pressed and the blocking gas valve on the pilot burner is open, gas flows through the solenoid valve to the blocking valve and then through the tee through the gas pipeline to the pilot burner.
With normal draft in the chimney (a vacuum of at least 1.96 Pa), the thermocouple, heated by the flame of the pilot burner, transmits an impulse to the valve solenoid, which in turn automatically holds the valve open and provides gas access to the blocking valve.
In case of violation of draft or its absence, the electromagnetic valve stops the gas supply to the device.
Rules for installing a flowing gas water heater A flowing water heater is installed in a one-story room in compliance with specifications. The height of the room must be at least 2 m. The volume of the room must be at least 7.5 m3 (if in a separate room). If the water heater is installed in a room with a gas stove, then it is not necessary to add the volume of the room for the installation of the water heater to the room with the gas stove. In the room where the instantaneous water heater is installed, should there be a chimney, a ventilation duct, a gap? 0.2 m 2 from the area of the door, window with an opening device, the distance from the wall must be 2 cm for an air gap, the water heater must be hung on a wall made of non-combustible material. If there are no fireproof walls in the room, it is allowed to install the water heater on a fireproof wall at a distance of at least 3 cm from the wall. The surface of the wall in this case must be insulated with roofing steel over an asbestos sheet 3 mm thick. The upholstery should protrude 10 cm from the body of the water heater. When installing the water heater on a wall lined with glazed tiles, no additional insulation is required. The horizontal distance in the light between the protruding parts of the water heater must be at least 10 cm. The temperature of the room in which the device is installed must be at least 5 0 С.
It is forbidden to install a gas instantaneous water heater in residential buildings above five floors, in the basement and in the bathroom.
How complicated household appliance, the column has a set of automatic mechanisms that ensure the safety of operation. Unfortunately, many old models installed in apartments today contain a far from complete set of security automation. And for a significant part of these mechanisms have long been out of order and have been disabled.
The use of dispensers without safety automatics, or with automatics turned off, is fraught with a serious threat to the safety of your health and property! Security systems are. Reverse thrust control. If the chimney is blocked or clogged and combustion products flow back into the room, the gas supply should automatically stop. Otherwise, the room will fill with carbon monoxide.
1) Thermoelectric fuse (thermocouple). If during the operation of the column there was a short-term cessation of the gas supply (i.e. the burner went out), and then the supply resumed (gas went out when the burner went out), then its further flow should automatically stop. Otherwise, the room will be filled with gas.
The principle of operation of the blocking system "water-gas"
The blocking system ensures that gas is supplied to the main burner only when hot water is drawn. Consists of a water unit and a gas unit.
The water assembly consists of a body, a cover, a membrane, a plate with a stem and a Venturi fitting. The membrane divides the internal cavity of the water unit into submembrane and supramembrane, which are connected by a bypass channel.
When the water intake valve is closed, the pressure in both cavities is the same and the membrane occupies the lower position. When the water intake is opened, the water flowing through the Venturi fitting injects water from the supra-membrane cavity through the bypass channel and the water pressure in it drops. The membrane and the plate with the stem rise, the stem of the water unit pushes the stem of the gas unit, which opens the gas valve and the gas enters the burner. When the water intake is stopped, the water pressure in both cavities of the water unit is leveled and, under the influence of a conical spring, the gas valve lowers and stops gas access to the main burner.
The principle of operation of automation to control the presence of a flame on the igniter.
Provided by the operation of EMC and thermocouple. When the igniter flame weakens or goes out, the thermocouple junction does not heat up, EMF is not emitted, the electromagnet core is demagnetized and the valve closes by spring force, shutting off the gas supply to the apparatus.
The principle of operation of traction safety automatics.
§ Automatic shutdown of the device in the absence of draft in the chimney is provided by: 21 Draft sensor (DT) EMC with thermocouple Igniter.
DT consists of a bracket with a bimetallic plate fixed on it at one end. A valve is fixed at the free end of the plate, which closes the hole in the sensor fitting. The DT fitting is fixed in the bracket with two lock nuts, with which you can adjust the height of the nozzle outlet plane relative to the bracket, thereby adjusting the tightness of the valve closure.
In the absence of draft in the chimney, the flue gases go outside under the hood and heat the bimetallic plate DT, which, bending, raises the valve, opening the hole in the fitting. The main part of the gas, which should go to the igniter, exits through the hole in the sensor fitting. The flame on the igniter decreases or goes out, heating of the thermocouple stops. The EMF in the electromagnet winding disappears and the valve shuts off the gas supply to the apparatus. The response time of the automation should not exceed 60 seconds.
Scheme of safety automation VPG-23 Scheme of safety automation of instantaneous water heaters with automatic shutdown gas supply to the main burner in the absence of draft. This automation works on the basis of the electromagnetic valve EMK-11-15. The draft sensor is a bimetallic plate with a valve, which is installed in the area of the water heater's draft interrupter. In the absence of thrust, hot combustion products wash over the plate, and it opens the sensor nozzle. In this case, the flame of the pilot burner is reduced, as the gas rushes to the sensor nozzle. The thermocouple of the EMK-11-15 valve cools down and it blocks the gas access to the burner. The solenoid valve is built into the gas inlet, in front of the gas cock. The EMC is powered by a chromel-copel thermocouple introduced into the flame zone of the pilot burner. When the thermocouple is heated, the excited TEDS (up to 25mV) enters the winding of the electromagnet core, which holds the valve connected to the armature in the open position. The valve is opened manually using a button located on the front wall of the device. When the flame goes out, the spring-loaded valve, which is not retained by the electromagnet, shuts off gas access to the burners. Unlike other solenoid valves, in the EMK-11-15 valve, due to the sequential operation of the lower and upper valves, it is impossible to forcibly turn off the safety automatics by locking the lever in the pressed state, as consumers sometimes do. As long as the lower valve does not block the gas passage to the main burner, the flow of gas to the pilot burner is not possible.
For blocking thrust, the same EMC and the effect of extinguishing the pilot burner are used. A bimetallic sensor located under the upper hood of the apparatus, when heated (in the zone of the return flow of hot gases that occurs when the draft is stopped), opens the gas discharge valve from the pilot burner pipeline. The burner goes out, the thermocouple cools down and the electromagnetic valve (EMC) shuts off gas access to the apparatus.
Maintenance of the machine 1. The owner is responsible for the supervision of the operation of the machine, and it is the responsibility of the owner to keep it clean and in good condition.
2. To ensure the normal operation of the instantaneous gas water heater, it is necessary to carry out a preventive inspection at least once a year.
3. Periodic maintenance flow gas water heater is made by employees of the gas facilities in accordance with the requirements of the rules of operation in the gas facilities at least once a year.
The main malfunctions of the water heater
|
Broken water plate |
Change plate |
||
|
Scale deposits in the heater |
Rinse the heater |
||
|
Main burner ignites with a pop |
Clogged faucet or nozzle openings |
clean the holes |
|
|
Insufficient gas pressure |
Increase gas pressure |
||
|
The tightness of the sensor on draft is broken |
Adjust traction sensor |
||
|
When the main burner is turned on, the flame knocks out |
Ignition retarder out of adjustment |
adjust |
|
|
Soot deposits on the heater |
Clean the heater |
||
|
When the water intake is turned off, the main burner continues to burn |
Broken safety valve spring |
Replace spring |
|
|
Safety valve seal wear |
Replace seal |
||
|
Foreign bodies under the valve |
Clear |
||
|
Insufficient water heating |
Low gas pressure |
Increase gas pressure |
|
|
Clogged faucet or nozzle hole |
clean the hole |
||
|
Soot deposits on the heater |
Clean the heater |
||
|
Bent safety valve stem |
Replace stem |
||
|
Low water consumption |
Clogged water filter |
Clean the filter |
|
|
The water pressure adjustment screw is too tight |
Loosen the adjusting screw |
||
|
Clogged hole in venturi |
clean the hole |
||
|
Scale deposits in the coil |
Flush the coil |
||
|
The water heater makes a lot of noise |
Large water consumption |
Reduce water consumption |
|
|
The presence of burrs in the Venturi tube |
Remove burrs |
||
|
Skewed gaskets in the water unit |
Correctly install gaskets |
||
|
After a short period of operation, the water heater switches off |
Lack of traction |
Clean the chimney |
|
|
Thrust sensor leaking |
Adjust traction sensor |
Electrical circuit break
There are a lot of reasons for circuit failures, they are usually the result of a break (breaking of contacts and joints) or, conversely, a short circuit before the electric current generated by the thermocouple enters the electromagnet coil and thereby ensures a stable attraction of the armature to the core. Circuit breaks, as a rule, are observed at the junction of the thermocouple terminal and a special screw, at the point where the core winding is attached to curly or connecting nuts. Short circuits can occur within the thermocouple itself due to careless handling (breaks, bends, shocks, etc.) during maintenance or failure due to excessive service life. This can often be observed in those apartments where the ignition burner of the water heater burns all day, and often for a day, in order to avoid the need to ignite it before turning on the water heater, which the hostess can have more than a dozen during the day. Circuit closures are also possible in the electromagnet itself, especially when the insulation of a special screw made of washers, tubes and similar insulating materials is displaced or broken. It will be natural in order to accelerate repair work everyone involved in their implementation, to have a spare thermocouple and an electromagnet with them at all times.
A locksmith looking for the cause of a valve failure must first get a clear answer to the question. Who is to blame for a valve failure - a thermocouple or a magnet? The thermocouple is replaced first, as the simplest option (and the most common). Then, with a negative result, the electromagnet is subjected to the same operation. If this does not help, then the thermocouple and electromagnet are removed from the water heater and checked separately, for example, the thermocouple junction is heated by the flame of the upper burner gas stove in the kitchen and so on. Thus, the locksmith installs the defective assembly by elimination, and then proceeds directly to the repair or simply replacing it with a new one. Only an experienced, qualified locksmith can determine the cause of the failure of the solenoid valve in operation, without resorting to a phased study by replacing supposedly faulty components with known good ones.
Used Books
1) Reference book on gas supply and use of gas (N.L. Staskevich, G.N. Severinets, D.Ya. Vigdorchik).
2) Handbook of a young gas worker (K.G. Kazimov).
3) Synopsis on special technology.
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These water heaters (Table 133) (GOST 19910-74) are installed mainly in gasified residential buildings equipped with plumbing, but not having a centralized hot water supply. They provide fast (within 2 minutes) heating of water (up to a temperature of 45 ° C), continuously coming from the water supply.
According to the equipment of automatic and control devices, the devices are divided into two classes.
Table 133
Note. Devices of type 1 - with the removal of combustion products into the chimney, type 2 - with the removal of combustion products into the room.
Top-class devices (B) have automatic safety and regulation devices that provide:
b) shutdown of the main burner in the absence of vacuum in
Chimney (apparatus type 1);
c) regulation of water flow;
d) regulation of the flow or pressure of gas (only natural).
All devices are provided with an externally controlled ignition device, and type 2 devices with an additional temperature selector.
Apparatuses of the first class (P) are equipped with automatic ignition devices that provide:
a) gas access to the main burner only in the presence of a pilot flame and water flow;
b) shutdown of the main burner in the absence of vacuum in the chimney (apparatus type 1).
The pressure of the heated water at the inlet is 0.05-0.6 MPa (0.5-6 kgf / cm²).
Appliances must have gas and water filters.
The devices are connected to water and gas pipelines using union nuts or couplings with lock nuts.
Symbol of a water heater with a rated heat load of 21 kW (18 thousand kcal / h) with the removal of combustion products into the chimney, operating on gases of the 2nd category, the first class: VPG-18-1-2 (GOST 19910-74).
Flowing gas water heaters KGI, GVA and L-3 are unified and have three models: VPG-8 (flowing gas water heater); HSV-18 and HSV-25 (Table 134).
Rice. 128. Flowing gas water heater HSV-18
1 - cold water pipe; 2 - gas valve; 3 - ignition burner; 4-gas outlet device; 5 - thermocouple; 6 - solenoid valve; 7 - gas pipeline; 8 - hot water pipe; 9 - thrust sensor; 10 - heat exchanger; 11- main burner; 12 - water-gas block with a nozzle
Table 134
| Indicators | Water heater model | ||
| HSV-8 | HSV-18 | HSV-25 | |
| Thermal load, kW (kcal/h) Heat output, kW (kcal/h) Permissible water pressure, MPa (kgf/cm²) |
9,3 (8000) 85 | 2,1 (18000)
18 (15 300) 0,6 (6) |
2,9 (25 000) 85
25 (21 700) 0,6 (6) |
| Gas pressure, kPa (kgf / m 2): natural liquefied The volume of heated water for 1 min at 50 ° C, l Diameter of fittings for water and gas, mm Diameter of a branch pipe for removal of products of combustion, mm |
|||
| Overall dimensions, mm; | |||
Table 135. TECHNICAL DATA OF GAS WATER HEATERS
| Indicators | Water heater model | |||
| KGI-56 | GVA-1 | GVA-3 | L-3 | |
| 29 (25 000) | 26 (22 500) | 25 (21 200) | 21 (18 000) | |
| Gas consumption, m 3 /h; | ||||
| natural | 2.94 | 2,65 | 2,5 | 2,12 |
| liquefied | - | - | 0,783 | |
| Water consumption, l/mn, temperature 60°C | 7,5 | 6 | 6 | 4,8 |
| Diameter of a branch pipe for removal of products of combustion, mm | 130 | 125 | 125 | 128 |
| Connecting fitting diameter D mm: | ||||
| cold water | 15 | 20 | 20 | 15 |
| hot water | 15 | 15 | 15 | 15 |
| gas Dimensions, mm: height |
15 950 | 15 885 | 15 | 15 |
| width | 425 | 365 | 345 | 430 |
| depth | 255 | 230 | 256 | 257 |
| Weight, kg | 23 | 14 | 19,5 | 17,6 |
The main components of a flowing water heater (Fig. 12.3) are: a gas burner, a heat exchanger, an automation system and a gas outlet.
Low pressure gas is fed into the injection burner 8 . The combustion products pass through the heat exchanger and are discharged into the chimney. The heat of the combustion products is transferred to the water flowing through the heat exchanger. A coil is used to cool the fire chamber. 10 , through which water circulates passing through the heater.
Gas instantaneous water heaters equipped with gas exhaust devices and draft breakers, which in the event of a short-term traction disturbance prevent the flame from extinguishing
gas burner device. There is a flue pipe for connection to the chimney.
Flowing water heaters are designed to produce hot water where it is not possible to provide it in a centralized manner (from a boiler house or heating plant), and are classified as instantaneous devices.
Rice. 12.3. circuit diagram instantaneous water heater:
1 – reflector; 2 – top cap; 3 – bottom cap; 4 – heater; 5 – igniter; 6 – casing; 7 – block crane; 8 – burner; 9 – fire chamber; 10 – coil
The devices are equipped with gas exhaust devices and draft breakers, which prevent the extinguishing of the flame of the gas burner device in the event of a short-term violation of draft. For accession to the smoke channel there is a smoke outlet branch pipe.
According to the rated thermal load, the devices are divided into:
With a rated thermal load of 20934 W;
With a rated thermal load of 29075 W.
The domestic industry mass-produces water-heating flow gas household appliances VPG-20-1-3-P and VPG-23-1-3-P. The technical characteristics of these water heaters are given in Table. 12.2. Currently, new types of water heaters are being developed, but their design is close to the current ones.
All the main elements of the device are mounted in an enameled casing of a rectangular shape.
The front and side walls of the casing are removable, which creates convenient and easy access to the internal components of the device for routine inspections and repairs without removing the device from the wall.
Water-heating flow-through gas apparatuses of the HSV type are used, the design of which is shown in fig. 12.4.
On the front wall of the casing of the device there is a gas cock control knob, a button for turning on the solenoid valve and a viewing window for observing the flame of the pilot and main burners. On top of the apparatus there is a gas exhaust device that serves to discharge combustion products into the chimney, on the bottom there are branch pipes for connecting the apparatus to gas and water networks.
Gas instantaneous water heaters
The main components of a flowing water heater (Fig. 12.3) are: a gas burner, a heat exchanger, an automation system and a gas outlet.
Low pressure gas is fed into the injection burner 8 . The combustion products pass through the heat exchanger and are discharged into the chimney. The heat of the combustion products is transferred to the water flowing through the heat exchanger. A coil is used to cool the fire chamber. 10 , through which water circulates passing through the heater.
Gas instantaneous water heaters are equipped with gas venting devices and draft breakers, which prevent the flame from extinguishing in the event of a short-term violation of draft
gas burner device. For connection to the chimney there is a chimney pipe.
Flowing water heaters are designed to produce hot water where it is not possible to provide it in a centralized manner (from a boiler house or heating plant), and are classified as instantaneous devices.
Rice. 12.3. Schematic diagram of instantaneous water heater:
1 – reflector; 2 – top cap; 3 – bottom cap; 4 – heater; 5 – igniter; 6 – casing; 7 – block crane; 8 – burner; 9 – fire chamber; 10 – coil
The devices are equipped with gas exhaust devices and draft breakers, which prevent the extinguishing of the flame of the gas burner device in the event of a short-term violation of draft. For connection to the smoke channel there is a smoke outlet.
According to the rated thermal load, the devices are divided into:
With a rated thermal load of 20934 W;
With a rated thermal load of 29075 W.
The domestic industry mass-produces water-heating flow gas household appliances VPG-20-1-3-P and VPG-23-1-3-P. The technical characteristics of these water heaters are given in Table. 12.2. Today, new types of water heaters are being developed, but their design is close to the current ones.
All the main elements of the device are mounted in an enameled casing of a rectangular shape.
The front and side walls of the casing are removable, which creates convenient and easy access to the internal components of the device for routine inspections and repairs without removing the device from the wall.
Water-heating flow-through gas apparatuses of the HSV type are used, the design of which is shown in fig. 12.4.
On the front wall of the casing of the device there is a gas cock control knob, a button for turning on the solenoid valve and a viewing window for observing the flame of the pilot and main burners. On top of the apparatus there is a gas exhaust device that serves to discharge combustion products into the chimney, below - branch pipes for connecting the apparatus to gas and water networks.
The device has the following units: gas pipeline 1 , blocking gas valve 2 , ignition burner 3 , main burner 4 , cold water connection 5 , water-gas unit with burner tee 6 , heat exchanger 7 , automatic traction safety device with solenoid valve 8 , thrust sensor 9 , hot water connection 11 and gas outlet 12 .
The principle of operation of the apparatus is as follows. Gas through the pipe 1 enters the solenoid valve, the power button of which is located to the right of the gas cock power handle. The gas shut-off valve of the water and gas burner unit performs a forced sequence of turning on the pilot burner and supplying gas to the main burner. The gas cock is equipped with one handle, turning from left to right with fixation in three positions. The extreme left position corresponds to closing the gas supply to the pilot and main burners. The middle fixed position (turning the knob to the right until it stops) corresponds to the full opening of the valve for gas supply to the pilot burner when the valve to the main burner is closed. The third fixed position, achieved by pressing the valve handle in the axial direction until it stops, followed by turning all the way to the right, corresponds to the complete opening of the valve for gas supply to the main and pilot burners. In addition to the manual blocking of the valve, there are two automatic blocking devices on the gas path to the main burner. Blocking the flow of gas to the main burner 4 with mandatory operation of the pilot burner 3 provided by a solenoid valve.
Blocking the gas supply to the burner, based on the presence of water flow through the apparatus, is performed by a valve driven through a stem from a membrane located in the water-gas burner unit. When the button of the valve solenoid is pressed and the shut-off gas valve is open to the pilot burner, gas through the solenoid valve enters the shut-off valve and then through the tee through the gas pipeline to the pilot burner. With normal draft in the chimney (vacuum is at least 2.0 Pa). The thermocouple, heated by the flame of the pilot burner, transmits an impulse to the solenoid valve, which automatically opens the gas supply to the blocking valve. In case of draft failure or its absence, the bimetallic plate of the draft sensor is heated by the outgoing products of gas combustion, opens the draft sensor nozzle, and the gas that enters the pilot burner during normal operation of the apparatus leaves through the draft sensor nozzle. The ignition burner flame goes out, the thermocouple cools down, and the solenoid valve turns off (within 60 s), i.e. stops the gas supply to the apparatus. To ensure smooth ignition of the main burner, an ignition retarder is provided, which operates as a check valve when water flows out of the above-membrane cavity, partially blocking the valve section and thereby slowing down the upward movement of the membrane, and, consequently, the ignition of the main burner.
Table 12.2
Specifications instantaneous gas water heaters
| Characteristic | Water heater brand | |||
| HSV-T-3-P I | HSV-20-1-3-P I | HSV-231 | HSV-25-1-3-B | |
| Thermal power of the main burner, kW | 20,93 | 23,26 | 23,26 | 29,075 |
| Nominal gas consumption, m 3 / h: natural liquefied | 2,34-1,81 0,87-0,67 | 2,58-2,12 0,96-0,78 | 2,94 0,87 | no more than 2.94 no more than 1.19 |
| Water consumption during heating at 45 °С, l/min, not less than | 5,4 | 6,1 | 7,0 | 7,6 |
| Water pressure in front of the apparatus, MPa: minimum nominal maximum | 0,049 0,150 0,590 | 0,049 0,150 0,590 | 0,060 0,150 0,600 | 0,049 0,150 0,590 |
| Vacuum in the chimney for normal operation of the device Pa | ||||
| Apparatus dimensions m: height width depth | ||||
| Apparatus weight, kg, not more than | 15,5 |
The upper class includes the water-heating flow-through apparatus VPG-25-1-3-V (Table 12.2). It manages all processes automatically. This ensures: gas access to the pilot burner only if there is a flame on it and a water flow; stopping the gas supply to the main and pilot burners in the absence of vacuum in the chimney; gas pressure (flow) regulation; regulation of water flow; automatic ignition of the pilot burner. AGV-80 storage water heaters (Fig. 12.5) are still widely used, consisting of a sheet steel tank, a burner with an igniter and automation devices (an electromagnetic valve with a thermocouple and a thermostat). A thermometer is installed at the top of the water heater to monitor the water temperature.
Rice. 12.5. Automatic gas water heater AGV-80
1 – traction chopper; 2 – thermometer sleeve; 3 – traction automatic safety unit;
4 – stabilizer; 5 – filter; 6 – magnetic valve; 7– - thermostat; 8 – gas valve; 9 – ignition burner; 10 – thermocouple; 11 – damper; 12 – diffuser; 13 – main burner; 14 – fitting for supplying cold water; 15 – tank; 16 – thermal insulation;
17 – casing; 18 – branch pipe; for hot water outlet to apartment wiring;
19 – safety valve
The safety element is a solenoid valve 6 . Gas entering the valve body from the gas pipeline through the valve 8 , lighting the igniter 9 , heats the thermocouple and enters the main burner 13 , on which the gas is ignited from the igniter.
Table 12.3
Technical characteristics of gas water heaters
with water circuit
| Characteristic | Water heater brand | |||
| AOGV-6-3-U | AOGV-10-3-U | AOGV-20-3-U | AOGV-20-1-U | |
| Dimensions, mm: diameter height width depth | – – | – – | – | – – |
| The area of the heated room, m 2, no more | 80–150 | |||
| Rated thermal power of the main burner, W | ||||
| Rated thermal power of the pilot burner, W | ||||
| Water temperature at the outlet of the apparatus ͵ °С | 50–90 | 50–90 | 50–90 | 50–90 |
| Minimum vacuum in the chimney, Pa | ||||
| Temperature of combustion products at the outlet of the apparatus, °C, not less than | ||||
| Connecting pipe thread fittings, inch: for inlet and outlet of water for gas supply | 1½ 1½ | 1½ 1½ | ¾ | ¾ |
| Efficiency, %, not less than |
Automatic gas water heater AGV-120 is designed for local hot water supply and space heating up to 100 m2. The water heater is a vertical cylindrical tank with a capacity of 120 liters, enclosed in a steel casing. In the furnace part there is a cast-iron injection gas-burner low pressure, to which a bracket with an igniter is attached. Gas combustion and maintaining a certain water temperature are automatically regulated.
The scheme of automatic regulation is two-position. The main elements of the automatic control and safety unit are a bellows thermostat, an igniter, a thermocouple and an electromagnetic valve.
Water heaters with a water circuit type AOGV operate on natural gas, propane, butane and their mixtures.
Rice. 12.6. Heating gas apparatus AOGV-15-1-U:
1 - thermostat; 2 – thrust sensor; 3 - shut-off and control valve;
4 - shut-off valve; 5 – fitting of the ignition burner; 6 – filter;
7 - thermometer; 8 - fitting direct (hot) water supply; 9 – connecting tube (general); 10 - tee; 11 – a connecting tube of the gauge of draft; 12 - impulse pipeline of the pilot burner; 13 - safety valve; 14 – connecting tube of the flame extinction sensor; 15 - fixing bolt; 16 - asbestos lining; 17 - facing; 18 – flame extinguishing sensor; 19 - collector; 20 – gas pipeline
AOGV type devices, unlike storage water heaters, are used only for heating.
The AOGV-15-1-U apparatus (Fig. 12.6), made in the form of a rectangular pedestal with a white enamel coating, consists of a heat exchanger boiler, a smoke exhaust pipe with a control damper as a draft stabilizer, a casing, a gas burner device and an automatic control and safety unit.
Gas from the filter 6 enters the shut-off valve 4 from which there are three outputs:
1) main - to the shut-off and control valve 3 ;
2) to fitting 5 top cover for supplying gas to the pilot burner;
3) to the fitting of the bottom cover for supplying gas to the draft sensors 2 and extinguishing the flame 18 ;
Through the shut-off and control valve, gas enters the thermostat 1 and through the gas pipeline 20 into the collector 19 , from where it is fed through two nozzles to the confuser of burner nozzles, where it mixes with primary air, and then goes into the furnace space.
Rice. 12.7. Burners vertical ( but) and adjustable with horizontal
tubular mixer ( b):
1 - cap; 2 - fire nozzle; 3 – diffuser; 4 - gate; 5 – nozzle nipple;
6 – nozzle body; 7 - threaded bushing; 8 - mixing tube; 9 – mouthpiece-mixer
Gas instantaneous water heaters - the concept and types. Classification and features of the category "Gas instantaneous water heaters" 2017, 2018.
