Solar water heater: building a do-it-yourself installation

Mounting

It remains only to fix the SV at the place of its further work.

If we are talking about a storage tank, then it is important to install reliable supports.The load from the weight of the tank itself, and even with water, will be considerable, so the frame of the shower or other support must be reinforced with metal corners

The length of the pipeline between the tank and the boiler must be minimal

The load from the weight of the tank itself, and even with water, will be considerable, so the frame of the shower or other support must be reinforced with metal corners. The length of the pipeline between the tank and the boiler must be kept to a minimum.

Flow-through SVs are installed on roofs or other hills so that at any time of the day, nearby objects do not block the light (fence, neighboring buildings, trees, etc.).

The slope of the solar collector is fixed (optimal for summer - 35).

Even simple homemade water heaters can save up to 60% on electricity costs. And don't let the opinion that the Russian climate is too cold for such technologies stop you. In the Moscow region, for example, the annual rate of solar energy is the same as in Germany, and there solar technologies are used with success!

Which one to choose for the pool?

The choice of a solar heater for a swimming pool is determined by its size, water volume, location and other criteria. Solar water heaters, the prices and parameters of which are in the best combination, can be manufactured in different design options. All available options can be used, from the simplest open structures to the most complex and expensive condensate chamber systems.

The simpler the complex, the cheaper and more reliable it is, but its efficiency will be correspondingly lower. The main selection criterion should be considered the size of the artificial reservoir and the frequency of recharge from the outside.Experts recommend for household purposes to do with simple and cheap flexible models, which are rubber planes with tubes soldered inside through which water is passed. They are inexpensive, but provide enough heat to maintain a normal temperature in the pool.

If it is necessary to heat water in artificial reservoirs for public or commercial use, it is recommended to purchase full-fledged complexes from vacuum tubes, or panel structures. They demonstrate high efficiency and allow you to get a sufficient amount of thermal energy. The parameters of such installations are detailed in the passport, which allows you to choose the complex that is most suitable in terms of performance.

How to make selective coating

The high efficiency collector has a high degree of absorption of solar energy. The rays fall on a dark surface, after which they heat it. The less radiation is repelled from the absorber of the solar collector, the more heat remains in the solar system.{banner_downtext}In order to ensure sufficient heat storage, it is necessary to create a selective coating. There are several production options:

• Homemade selective collector coating - use any black paint that, after drying, leaves a matte surface. There are solutions when an opaque dark oilcloth is used as a collector absorber. Black enamel is applied to the heat exchanger pipes, the surface of cans and bottles, with a matte effect.

Special absorbent coatings - you can go the other way by purchasing a special selective paint for the collector.The composition of selective coatings includes polymer plasticizers and additives that provide good adhesion, heat resistance and a high degree of absorption of sunlight.

Solar systems used exclusively for heating water in the summer may well get by with painting the absorber black with ordinary paint. Homemade solar collectors for heating a house in winter should have a high-quality selective coating. You can't skimp on paint.

Homemade or factory solar system - which is better

It is unrealistic to make a solar collector at home that can be compared with factory products in terms of technical characteristics and performance. On the other hand, if you just need to provide enough water for an outdoor shower, solar energy will be enough to operate a simple homemade water heater.

As for liquid collectors operating in winter, not even all factory solar systems can operate at low temperatures. All-weather systems, these are most often devices with vacuum heat pipes, with increased efficiency, capable of operating up to a temperature of -50 ° C.

Factory solar collectors are often equipped with a rotary mechanism that automatically adjusts the angle of inclination and direction of the panel to the cardinal points, depending on the location of the Sun.

An efficient solar water heater is one that is fully consistent with the tasks assigned to it. To heat water for 2-3 people in the summer, you can get by with an ordinary solar collector made with your own hands from improvised means. For heating in winter, despite the initial costs, it is better to install a factory solar system.

Video course on the manufacture of panel solar water heater

In which system to integrate a solar water heater

To hot water began to flow from the tap, it is important not only to choose a collector, but also to create a whole system for it from a storage tank, connecting pipes, taps and other elements

Circulation types

It is necessary to determine whether you can install the storage tank above the level of the collector. It depends on which of the two types of circulation will be in the system.

1. Natural circulation is created due to the difference in density between cold and hot water. The heated liquid tends to rise, which causes such an arrangement of the storage tank. If the roof has a complex structure, choose a well-lit place to place the collector and place the tank under the ridge.

2. Forced circulation systems work thanks to a pump that pumps warm water into a prepared tank. In this case, it becomes possible to place the elements of the system far from each other, for example, to put a storage tank in the attic or in the basement. This is better for the exterior, requires less effort on the thermal insulation of the tank itself. But the pipes leading from the collector to the tank must be provided with thermal insulation, otherwise there is a risk of losing all the heat along the way. Forced circulation requires the use of electricity, so if there is no or often no electricity in the country, this option will not work.

If you decide to use a coolant oil in the manifold, provide a pump for forced circulation. Otherwise, due to the low expansion coefficient of the oil, the system simply will not work.

Selecting the type of circulation circuit

Three types of systems are common:

1. Open loop.This is the easiest way to supply hot water to your home. Its main difference is that the coolant in the collector is necessarily water. First, it is heated in tubes, then it enters the storage tank, and then directly into the faucet in the kitchen or bathroom. That is, water does not circulate in a circle, but in an open circuit, a new portion is heated each time.

2. Single-circuit. It is preferable when using solar heat it is supposed to heat the house or make the operation of electric heating cheaper. Its difference is that the water heated by the sun enters the heating pipes. The coolant moves in the system in a circle. This is the closed circulation cycle. Since the solar collector is used in winter and off-season, choose vacuum models and include an additional heater in the system. An electric or gas boiler helps to bring the coolant to the desired temperature on cold and cloudy days, as well as at night.

3. Dual circuit. This option involves the transfer of heat from the collector to the system through a special heat exchanger. Since there is no direct contact between the coolant and water, oil or antifreeze is used in the collector. The system is optimal for country houses in which people live throughout the year. In it, the collector is used for both hot water supply and heating at the same time. As a rule, a boiler and / or boiler for additional water heating is also integrated into it, and several collectors are used (in depending on quantity living and climatic characteristics of the region).

Features of using homemade products

Industrial instantaneous water heaters undergo a serious check, which prevents the appearance of defective units on sale that pose a danger to users. When making such a device yourself, you must clearly understand that no one but you will diagnose and detect malfunctions. If you do something wrong and do not notice it in time, then the entire burden of the consequences will fall on the one who is closest to the damaged unit. Therefore, before the first start-up and every 2-3 months, be sure to check the condition of the wires, contacts and welds.

Do not forget to open the water first, then turn on the heating element. Otherwise, the water in the unit will boil, and the tubular electric heater will burn out. In those devices that are sold in the store, a complex sensor is installed that reacts to the movement of water and supplies electricity to the heater coil.

Install homemade devices in places where human activity is minimal. This will protect you and your loved ones if for some reason the unit leaks. The coolant in the heating system is under pressure up to 1 atmosphere, so the length of the jet through the leak can reach 1 meter. Water with a temperature of 70-80 degrees can severely scald (burns of the second degree), so take these recommendations seriously.

A flowing water heater can be made independently, however, such a device will cost much more than a purchased unit and will be less efficient and safe. Therefore, its independent production is justified only if the models offered by stores do not suit you.

The principle of operation of a solar water heater

Modern heaters act as equipment for converting sunlight into thermal energy. They are able to heat the house and provide water heating mainly in sunny areas, provided that they are installed in a large open area.

There are many types of solar heaters, but they all work on the same principle. All systems consist of a circuit with a series of devices that transmit thermal energy. The basis of the device are solar batteries, working at the expense of solar collectors.

The collector is a collection of interconnected pipes. Water, non-freezing liquid or ordinary air circulate through them, which provide cooling for the mechanism. Circulation is provoked by evaporation and a change in pressure inside the system.

The accumulation of energy is provided by special absorbers. Absorber - an iron plate attached to pipes, with a blackened surface.

In the manufacture of the cover of the water heater, a material is used that is able to transmit sunlight without problems (usually it is impact-resistant glass). Materials from various polymers can not tolerate direct exposure to ultraviolet rays, therefore, when using them, a high-quality cooling system is installed (mainly antifreeze is used).

If the device is installed for heating a small room without its own heating system, then a small single-circuit structure is being built. It should be noted that it will work only in sunny summer. In the case of installing the heater in two-circuit designs, it should be borne in mind that the collector will process only one circuit.The main load will be placed on the heating system built into the room.

Despite the dependence of this type of heaters on sunny summer weather, the market demand is growing every year. They found their recognition among people seeking to use natural energy to the maximum.

Do-it-yourself water heating: how to make a solar water heater from a soldering iron

This is another option that allows you to provide your shower on the site with hot water. Only in this case, the use of a soldering iron is required, which means that electricity is needed. The design of this type includes a water tank and a water heater. If there is already a shower cabin with a roof-mounted tank designed only for the supply of warm water heated by the sun's rays, then it will not be difficult to connect a new device with a blowtorch to this system.

First you need to slightly change the water supply scheme itself. It is required to bring the pipes outside the shower cabin, since the heater with the heat exchanger must be located outside on a shelf fixed on the side wall of the shower cabin. In this case, an ordinary blowtorch is used as a heater, which is installed on a shelf in such a way that the combustion chamber enters the heat exchanger coil. As a result, it will be possible to regulate the temperature of the jets by changing the intensity of combustion and the water supply. Thanks to the use of a blowtorch, the entire preparation of this installation for operation is carried out within 1-2 minutes.

Water must be supplied from the tank, which is located on the roof of the shower cabin, through steel pipes (0.5 inches) to the heat exchanger.It is necessary to provide the outlet pipe with a shut-off valve, which will serve to completely shut off the system, for example in the case of installing a heat exchanger, etc. Another valve should be placed directly in the cabin in front of the shower screen. It is required to regulate the water supply.

The most complex element in this system is the heat exchanger. It includes a coil and casing. The coil can be made from steel pipe (0.5 inches) twisted into a spiral of three turns. Outwardly, the coil resembles a thick compressed spring. The coils of this spring must be the same. To do this, you need to wind a thin pipe onto a thicker one (1.5 inches). The finished coil must then be inserted into a casing made from a piece of pipe and fixed by welding. The free ends should be bent up and connected to the main water supply at the couplings. This connection will allow you to remove the heat exchanger for the winter to prevent freezing of water in the pipes, from which they can burst.

You can use another version of the heating system. It involves an increase in the volume of the heat exchanger, which will allow heating water to higher temperatures.

In this case, you will need to install a mixer in the system to add cold water to it. To this end, it is necessary to equip the tank with another outlet connected to the mixer. Then you need to connect a pipe from the heat exchanger to it. The presence of hot water and a mixer with cold will greatly simplify the adjustment of the installation.

The enlarged heat exchanger will differ from the usual one by the presence of a six-turn coil and an elongated casing. The mixer in this system is recommended to use a standard one for city apartments.It just needs a little tweaking. You will first need to remove the flexible shower hose, plug the hole with a plug, install a short pipe with a shower screen instead of a tap. The standard faucet can be replaced with a homemade faucet made from three pieces of pipe (0.5 inch diameter) and one piece of pipe (1.5 inch diameter).

Manufacturing Recommendations

For those who prefer simple solutions, there is an option invented by our grandfathers long ago. One or more black-painted tanks are installed on the roof of the house or a separate shower room. Such a water heater works simply: warm water flows through a vertical pipe from the barrel directly into the shower, you just need to open the tap. To fill the tank, a water main is laid to it. With good solar activity in the summer, the water in the barrel heats up in just a few hours.

A simple rooftop tank is not as efficient as a solar collector, even if it is homemade. Therefore, having decided on the dimensions of the heat sink, it is necessary to make a case, where the coil should then be placed. It is preferable to assemble it from wood, it does not transmit heat as much as metal. Before laying the heat exchanger, the back wall must be insulated with a layer of foam. The general scheme of a solar water heater with a storage and make-up tank is shown in the figure:

Just assembling a heat receiver with your own hands is not all the work, you need to properly use it in the water supply system.The solar water heating installation shown in the diagram consists of a tank - an accumulator, a recharge tank and the collector itself. Do not install unnecessary pumping equipment, you must allow the water to circulate naturally. It is necessary to ensure that the battery is slightly higher than the heat sink, and the make-up tank is higher than the accumulating one.

The hot water tank must be insulated; any rolled material is suitable for this. In order for the storage water heater to function in automatic mode, a float valve must be installed in the second tank, which reacts to a decrease in the liquid level. A pipe from the water supply is connected to the valve nozzle. Now, during the consumption in the main tank, when washing, cold water will be supplied to its lower zone. Do not forget to provide a vertical air outlet, raised to the required height.

Average prices

Due to the fact that an increasing number of inhabitants of our planet are trying to use alternative energy sources in everyday life to produce heat, electricity and hot water, therefore, the range of products offered is quite wide.

Solar water heaters are produced by enterprises in our country and abroad. On the The installation cost is affected by the country and manufacturer, the design (flat or vacuum) of the water heater, the delivery set and the region of purchase.

The cheapest option will cost the buyer 1,500.00 rubles, for this money you can purchase a "Solar water heater for the pool" company "Intex" (China) with the following technical characteristics: the size of the heater sheet - 1200 x 1200 mm, designed for use with filter pumps with a productivity no more than 9500 l/hour, weight — 3.7 kg.

Solar water heater "DACHA-LUX" (Russia) with a volume of 125.0 liters will cost the buyer 28,850.00 rubles. The delivery set of this device includes: storage tank, a set of vacuum tubes (15 pieces), a controller. The absorbing area is 2.35 m2.

The German installation for hot water supply "AuroSTEP plus" can be purchased for a price of 190,000.00 to 450,000.00 rubles, depending on the configuration. For this money, the buyer purchases: a hot water supply system that excludes the possibility of boiling (Drain-back design), a water heater with a capacity of 150 - 350 liters. and 1 - 3 solar collectors.

The unit is equipped with a control regulator and an additional electric heater.

As can be seen from the above figures, the spread in cost is very large, so each potential purchaser can choose a device in accordance with the requirements for it.

How to make a solar water heater at home?

We bring to your attention detailed instructions for making a solar boiler with your own hands. The process is quite laborious, but the result is worth it.

First you need to prepare the necessary materials and tools for the job. You will need:

• Glass 3-4 mm thick;
• Wooden slats 20x30 millimeters;

• A bar measuring 50x50 millimeters;
• Boards 20 mm thick and 150 wide;
• Tin strip or fasteners for pipes;
• OSB sheet or plywood 10 mm thick;
• metal corners;
• Furniture hinges;
• Tin strip or fasteners for pipes;
• Insulation with a metallized coating;
• Sheet of galvanized sheet;
• Mineral wool;
• Metal and copper pipes with a diameter of 10-15 millimeters and 50 millimeters.

• Connecting clamps and couplings;
• sealant;
• Black paint;
• Rubber seal for doors and windows;
• Aqua markers;
• Plastic barrel or metal tank with a volume of 200-250 liters.

Once everything you need for work has been prepared, you can proceed directly to the manufacture of a solar water heater. The process itself is divided into four stages, which we will discuss in more detail later.

Stage 1. Making the box

At the beginning of the whole process, you need to make a case for the future water heater. This should be done based on the following sequence of actions:

• From the prepared boards, assemble a box of the size you need.
• Sew up the bottom of the case with a sheet of plywood or OSB.

• Upon completion of the assembly of the box, seal all joints and cracks.
• Cover the inside of the case with a heat reflector. This way you avoid heat loss.
• Cover all surfaces with a layer of mineral wool.
• Close the finished layer of thermal insulation on top with tin sheets and seal all cracks with sealant.
• Paint the inside of the case with black paint.
• Install a glazing frame made of wooden frames. To do this, cut the rails to the sizes you need and connect them using metal corners for this purpose.
• Install glass on both sides of the frame, pre-treating one fourth of the rails with liquid consistency sealing material.
• Attach the frame to the base of the case using furniture hinges.
• Glue rubber seal strips to the ends of the case.
• Prime and paint all exterior surfaces of the water heater body.

That's all, the assembly of the case is completed. Now you can safely move on to the next step.

Stage 2. Making a radiator

You can make a radiator for a solar water heater by following the following course of action:

1. Prepare two pieces of pipe with a diameter of 20-25 millimeters and the length you need.
2. In a pipe with a large diameter, drill holes with a distance of about 10 centimeters from each other.
3. Insert the sections of previously prepared pipes into the holes so that the ends protrude 5 millimeters from the back side.
4. Weld or solder connections.
5. Diagonally to the ends of pipes with a diameter of 50 millimeters, weld threaded bends for external connections. The rest of the ends need to be muffled.
6. Paint the radiator with black heat-resistant paint in several layers.

Stage 3. Mounting the collector

Immediately before installing the radiator in the box, you first need to outline the places in its walls, through which the outlets will pass for connecting the supply and withdrawal pipes. Thereafter:

1. Holes of the required diameter are drilled according to these marks.
2. Next, install the radiator in the housing close to the bottom and fix it along the entire length of each element. This should be done in 4-5 places using strips of tin or other fasteners intended for this purpose.
3. Now the collector housing is covered with a frame and rigidly fixed with self-tapping screws or corners.
4. Further, all cracks are sealed.

Final stage. Arrangement and connection of a solar water heater:

• Insert threaded taps into the container that you are going to use as a heat accumulator. One point must be made at the bottom of the container for supplying cold water, and the second must be arranged at the top for the heated liquid.
• After - the container must be insulated using mineral or stone wool for this purpose, as well as other heat-insulating material.

• An aqua chamber complete with a float valve is mounted 0.5-0.8 meters above the tank in order to constantly create a constant low pressure in the system. In addition, half of one pipe should be used to install the pressure pipeline from the water supply to the aqua chamber.
• After the container is completely filled, water will flow from the drainage hole of the aqua chamber. Next, you can turn on the water supply from the water supply and fill the tank.

That's it, your solar water heater is ready!

Advantages and disadvantages of solar collectors

The main advantages of solar water heaters:

• use of an inexhaustible and absolutely free source of energy;
• the consumption of traditional energy sources - gas, oil, coal - is reduced;
• the possibility of working all year round;
• you can easily reduce or increase heat by removing / supplementing the number of sections;
• changes in energy prices do not affect the operation of solar plants;
• reliable performance, convenient operation for a long time.

Main disadvantages:

• the cost of the solar collector itself and its installation, together with the strapping with all the complementary elements, will cost a rather large amount - this is quite an expensive pleasure:
• It is far from always possible to ensure efficient autonomous operation of a solar collector due to the intermittent presence of the sun in the sky, so the use of a collector alone without additional energy sources does not provide a person's needs for thermal energy.

The purpose of the solar collector, its advantages and disadvantages

A solar water heater (liquid solar collector) is a device that heats a coolant with the help of solar energy. It is used for space heating, hot water supply, water heating in swimming pools, etc.

The solar collector will provide the house with hot water and heat

The prerequisite for using an eco-friendly water heater is the fact that solar radiation falls on the Earth all year round, although it differs in intensity in winter and summer. So, for middle latitudes, the daily amount of energy in the cold season reaches 1–3 kWh per 1 sq.m, while in the period from March to October this value varies from 4 to 8 kWh/m2. If we talk about the southern regions, then the figures can be safely increased by 20-40%.

As you can see, the efficiency of the installation depends on the region, but even in the north of our country, the solar collector will provide the need for hot water - the main thing is that there are fewer clouds in the sky. If we talk about the middle lane and the southern regions, then the solar-powered installation will be able to replace the boiler and cover the needs of the heating system coolant in winter. Of course, we are talking about productive water heaters of several tens of square meters.

Table: distribution of solar energy by region

Average daily amount of solar radiation, kW*h/m2
Murmansk	Arkhangelsk	St. Petersburg	Moscow	Novosibirsk	Ulan-Ude	Khabarovsk	Rostov-on-Don	Sochi	Nakhodka
2,19	2,29	2,60	2,72	2,91	3,47	3,69	3,45	4,00	3,99
Average daily amount of solar radiation in December, kW*h/m2
0,05	0,17	0,33	0,62	0,97	1,29	1,00	1,25	2,04
Average daily amount of solar radiation in June, kW*h/m2
5,14	5,51	5,78	5,56	5,48	5,72	5,94	5,76	6,75	5,12

Advantages of solar water heaters:

• relatively simple design;
• high reliability;
• efficient operation regardless of the season;
• long service life;
• the possibility of saving gas and electricity;
• no permission is required to install equipment;
• small mass;
• ease of installation;
• complete autonomy.

As for the negative points, not a single installation for obtaining alternative energy can do without them. In our case, the disadvantages are:

• high cost of factory equipment;
• dependence of the solar collector efficiency on the time of year and geographic latitude;
• susceptibility to hail;
• additional costs for the installation of a heat storage tank;
• dependence of the energy efficiency of the instrument on cloudiness.

Considering pros and cons of solar water heaters, do not forget about the environmental side of the issue - such installations are safe for humans and do not harm our planet.

The factory solar collector resembles a construction set, with which you can quickly assemble the installation of the required performance

Options for homemade solar installations

A feature of do-it-yourself solar water heaters is that almost all devices have the same design of a heat-insulated box. Often the frame is assembled from lumber and covered with mineral wool and a heat-reflecting film.As for the absorber, for its production they use metal and plastic pipes, as well as ready-made components from unnecessary household equipment.

From a garden hose

A snail-shaped garden hose or PVC plumbing pipe has a large surface area, which makes it possible to use such a circuit as a water heater for the needs of an outdoor shower, kitchen or pool heating. Of course, for these purposes it is better to take black materials and be sure to use a storage tank, otherwise the absorber will overheat during the peak of the summer heat.

A flat-plate garden hose collector is the easiest way to heat your pool water

From the condenser of an old refrigerator

The external heat exchanger of a used refrigerator or freezer is a ready-made solar collector absorber. All that remains to be done is to retrofit it with a heat-absorbing sheet and install it in the case. Of course, the performance of such a system will be small, but in the warm season, a water heater made from refrigeration equipment parts will cover the hot water needs of a small country house or cottage.

The heat exchanger of an old refrigerator is an almost ready-made absorber for a small solar heater

From a flat radiator heating system

The manufacture of a solar collector from a steel radiator does not even require the installation of an absorbing plate. It is enough to cover the device with black heat-resistant paint and mount it in a sealed casing. The performance of one installation is more than enough for a hot water supply system. If you make several water heaters, you can save on heating the house in cold sunny weather.By the way, a solar plant assembled from radiators will heat utility rooms, a garage or a greenhouse.

Steel heating system radiator will serve as the basis for the construction of an environmentally friendly water heater

From polypropylene or polyethylene pipes

Metal-plastic pipes, polyethylene and polypropylene, as well as fittings and fixtures for their installation, allow you to build the contours of solar systems of any size and configuration. Such installations have good performance and are used for space heating and hot water for household needs (kitchen, bathroom, etc.).

The advantage of a solar collector made of plastic pipes is low cost and ease of installation.

From copper pipes

Absorbers built from copper plates and tubes have the highest heat transfer, so they are successfully used for heating the coolant of heating systems and in hot water supply. The disadvantages of copper collectors include high labor costs and the cost of materials.

The use of copper pipes and plates for the manufacture of the absorber guarantees a high efficiency of the solar plant

How to make a simple water heater with your own hands

Polycarbonate

One of the options for manufacturing a solar water heater involves using in cellular polycarbonate structures. The only requirement for this structural element is the light transmission of the material. Strength is also an important characteristic, but not the main one.

From the available materials, it can be various lumber or light profile metal elements, the frame of the device is made.A coil is constructed from copper tubes, preferably in one plane - this is the absorber of the device through which water will circulate.

At the ends of the copper tube, fittings are mounted to connect the supply pipe and the outlet of heated water. As a coil, you can use a similar design from an old refrigerator, but in this case, the parameters of the refrigerator coil will determine the geometric dimensions of the entire device.

The coil is placed in the body, the whole structure is insulated with heat-insulating material and covered from the outside with a polycarbonate sheet.

The water heater is mounted on a selected site in accordance with the geographical location and is connected to the cold water supply and the hot water consumption system.

From plastic bottles

The simplest water heater that uses solar energy to heat water can be make from ordinary plastic bottles with a volume of 1.5 liters (or similar).

The only condition is the uniformity of this structural element.

An important condition for the operation of such a device is the tightness and strength of the connections between the bottles. The best option would be when a hole is drilled in the bottom of the bottle corresponding to the diameter of the neck of the bottle, which allows you to insert one bottle into another. For fastening, you can use the caps from the same bottles, having previously drilled holes in them.

By connecting in this way, you can assemble several batteries, each of which will contain 3-4 bottles. The number of bottles in the battery is chosen by each individual.

Depending on the number of bottles in the battery and the number of such batteries, the geometric dimensions of the device are obtained, on the basis of which the frame of the water heater is made. The frame, as in the previous case, can be made from the materials at hand. Insulation is laid and, if possible, the receiving surface is darkened (the inner surface of the bottom wall of the frame).

Batteries of bottles are placed in the frame, which are interconnected in such a way that the upper parts of the batteries are connected to the cold water supply from the water supply, and the lower parts are connected to the outlet pipe with heated water.

The front side of the frame is sewn up with glass, polycarbonate or other transparent material that transmits sunlight well and retains heat inside the device.

To ensure proper water heating, shut-off valves must be installed on the inlet and outlet pipes.