In this article we will touch on the problem of heating water. It happens that the task arises to heat water. This task most often arises in hotels, recreation centers, i.e. where it is necessary to provide a large number of people with hot water.
How can you heat water?
There are many ways to prepare hot water:
By using heat pump
By using gas boiler
Using a diesel boiler
Using a solid fuel boiler
Using an electric boiler or tenami
By using solar collector or panels
And so on, we won’t list everything, otherwise the article will turn out to be too long. We have listed the main methods. Everything seems simple: you have network gas, and you need to heat several boilers indirect heating. To do this, it is enough to connect the gas boiler and boilers with a pipeline. They called a plumber, bought pipes and fittings, the plumber put everything together - and voila!... the boilers do not even have time to heat up to 50°C.
What is the reason?
The thing is that your boiler is simply not suitable for heating such an amount of water. And most likely, you simply did not calculate the power sufficient to heat the water.
How to calculate the required power for heating water?
It's not very difficult task, and you can calculate the power required to heat water yourself. Arm yourself with a calculator, paper and pen. To heat one liter of water by one degree Celsius you need thermal power 1.16 W.
For example, you have a water container with a volume of 500 liters, and you need to heat the water in it from 20°C to 80°C. We believe that 80°C – 20°C = 60°C is our delta. 500 l. * 60°C * 1.16 W = 34,800 W/hour or 34.8 kW/hour. This is the required power to heat 500 liters, from 20 °C to 80 °C in one hour.
And if you have a gas boiler installed with a capacity of 25 kW/hour, then naturally it will not be able to heat 500 liters. water up to 80°C in one hour. Therefore, if the initial power is insufficient, these powers are compensated only by heating time. What entails an increase in boiler volume. In addition, you need to understand that heat losses still occur in the system. Therefore, the figures given are approximate.
It is worth noting that consumption hot water directly related to the number of people who use it. According to SNiP for hotels, with a shower in each room, water consumption per person will be 140 liters per day. According to our data, real consumption hot water in hotels is 50 liters per day, per person.
Heating of water with a solar collector.
Let's calculate how to heat water correctly with the sun. Let's imagine that there is a hotel in which the water needs to be heated using solar energy. This hotel has 40 triple rooms and 20 double rooms. We want to organize heating of hot water using solar energy.
We calculate the maximum occupancy of the hotel: (40*3) + (20*2) = 160 people will live in this hotel. They will need 160 people. * 50 liters = 8,000 liters of hot water per day. In hotels, as a rule, there are two peaks of water withdrawal: in the morning (from 8.00 to 10.00) and in the evening (from 17.00 to 20.00). This means that we need to provide at least 3,000 liters of hot water for the morning water draw, and at least 5,000 liters of water for the evening water draw, since the evening water draw is usually larger.
It is worth noting that by the term “hot water” we mean water with a temperature of 60°C. To avoid installing storage boilers with a volume of 5,000 liters, you can heat water up to 80°C. This will reduce the capacity volume to 3,500 liters.
We calculate the required power: 6,500 liters * 60 °C * 1.16 W, we get 452.4 kW/hour we need to spend to heat this amount of water.
How many solar collectors are needed?
Now we are counting how many solar collectors we will need. The roof of our hotel faces south, so we believe that solar vacuum collectors will operate at full capacity.
Power of one vacuum tube with 24mm. capacitor is conventionally equal to 65 W/hour. Solar collectors will operate 10 hours a day, from 9.00 to 19.00 ( perfect option). Under such conditions, one tube will produce 650 W/hour in one day. Divide 452.4 kW/hour by 0.65 kW/hour (650 W/hour) and we get 696 tubes. These are 23 solar collectors of 30 tubes each, or 35 collectors of 20 tubes each.
And how many collectors with 14 mm are needed? capacitor? One tube of such a collector produces at its peak about 50 W/hour or 500 W/hour in ten hours. Divide 452.4 kW/hour by 0.5 kW/hour (500 W/hour) and we get 905 tubes. These are 30 solar collectors of 30 tubes each or 45 solar collectors of 20 tubes each.
We carried out all these calculations under ideal conditions, in excellent sunny weather, and did not take into account water consumption during heating. If you need more accurate calculations, please contact us. We will calculate, supply equipment and install you an excellent and, most importantly, working solar system.
There are two main ways to prepare hot water. First, the water is heated while moving through the heater and supplied to the water tap. Such a heater is called a flow-through heater.
The second method is to heat a large volume of water in a thermally insulated container, then gradually consume it. Such a heater is called a storage heater. The energy source is usually gas, electricity or heated coolant from the heating system.
Flow-through – high peak power
The instantaneous heater must be relatively powerful in order to provide the required flow of hot water to the tap. For a shower head, a power of at least 10 kW is required, for filling a bath - from 15 kW, for two hot water taps - from 20 kW.
Heating water with an electric instantaneous heater is not cheap. In addition, you need a three-phase connection (over 6 kW) and a special permit for higher power.
It is optimal to provide several taps, install a compact electric one on each of them flow heater. At the same time, protection is installed against their simultaneous operation, so as not to overload the network.
More cheap option- heating water using gas. Are used geyser, or the second circuit of the heating boiler. The power of such devices can be enough for two taps, and hot water is cheaper.
Disadvantages of flow-through
With a flow-through circuit, the heater should be located as close to the tap as possible in order to drain less water until it gets hot. The recommended distance is no more than 5 meters. But in any case there will be excessive consumption of water and energy. A similar drawback is typical for a storage heater.
Another disadvantage of a flow-through DHW (hot water supply) circuit is the inability to pick up some hot water. Each device has its own minimum power. Therefore, when water flow is low, it simply does not turn on.
This also results in waste of water and energy.
Pressure surges in the system cause discomfort because they change the outlet water temperature.
IN retail outlets in order to sell an unsuitable flow-through electric heater, they simply indicate that it produces so many liters of water at such a temperature, for example, +50 degrees, which at first glance is acceptable. But it is not indicated at what temperature the water is heated. Key Feature of such an apparatus is the heating temperature difference. After all, cold water is usually +6 - +10 degrees, and not +15 or +20.
Storage water heating system
The main advantage of electric storage tank with a power of 1.5-2.0 kW is that it can be installed everywhere, in any house and apartment where there is a 220 V power supply. Its volume is usually 25 - 150 liters (running volume 50 - 100 liters). The water in it is heated gradually to a predetermined temperature, and when withdrawn, a large flow rate is possible; the temperature decreases gradually.
It is cheaper to heat water with a gas storage heater with a low-power burner (up to 3 kW). The fact is that such a heater does not require a special chimney. But it can only be installed in agreement with Gorgaz, probably by separate project. Provided with air from the room (with an exhaust system).
Disadvantages of savings
- Limited amount of water, which can create difficulties. For example, if one portion of the tank volume is consumed for bathing, then it takes a lot of time to prepare the next volume.
- The heater must be installed next to the water supply; if the bathroom and kitchen are separated, then a separate storage tank must be installed on each tap.
- Energy is wasted due to cooling of unused hot water in the heater.
- Excessive consumption of water when draining water from the tap, which has cooled in the pipeline.
Indirect heating boiler - stable hot water system
The advantage of an indirect heating boiler is that it uses energy from the heating system for heating, which is abundant and usually not expensive. Therefore, there can be a lot of hot water, its temperature is stable, and water is cheaper.
An indirect heating boiler is a storage tank with a capacity of 100 - 300 liters. Heating is carried out by a spiral pipeline through which the coolant heated to 80 - 90 degrees moves.
Heating systems are created in such a way that when the hot water supply cools below a threshold value, for example +50 degrees, the boiler switches to heating the boiler. At the same time it issues elevated temperature operates at full power, heating the hot water supply to the upper threshold value, for example, +60 degrees. After which it switches back to heating.
With buffer capacity – the largest energy reserve
In a buffer tank, the opposite is true - a large-volume container is used, about 1 ton or more filled with coolant, and the heated water moves in a spiral, i.e. direct-flow heating occurs. But when additional taps are opened, its temperature changes slightly, since the design has a large reserve in terms of the amount of transmitted energy.
The temperature of the hot water will be the same as that of the heating fluid. Sometimes this is not suitable, so the water supply scheme also includes mixing unit to reduce temperature...
Heating systems with solid fuel boilers are mainly supplied with a buffer tank.
Other features of heating water by heating
Single-circuit gas or liquid boilers are often equipped with a boiler.
Another feature of the system is the ability to create constant circulation of water through a ring water supply pipeline. Then, when you open the tap, you immediately get hot water. Cooling of water is not considered a loss of energy, because it is spent on heating the house.
There is still an opportunity to save - an additional heating coil is placed in the boiler and connected to the solar collector. The sun's energy is called free energy, the consumption of solar collectors is in this case pays off. This makes it possible to heat water in the summer; if there is not enough energy, the boiler is connected.
Layered heating boiler
The main disadvantages of a conventional direct-flow heating system with gas heater(second circuit of the boiler) or electric is solved by installing a layer-by-layer heating boiler. One or more per tap. It is a heat-insulated container into which hot water is supplied from above. Its fence is also carried out from the same level.
Such a boiler makes it possible to simultaneously obtain a lot of hot water at a stable temperature. With it you can pick up “a little water” and also ensure the least amount of cold drainage. A conventional heating boiler can also be used as such an intermediate storage tank.
Error - incorrect connection of the DHW boiler
One of the common mistakes when creating a hot water supply system in a house is connecting an indirect heating boiler to the second circuit of a double-circuit boiler. This circuit itself is designed for preparing hot water, so it has a maximum temperature limit of +60 degrees to prevent thermal burns.
Now the most comfortable and economical solution to create a hot water supply system is to install an indirect heating boiler, where this can be done. The rest of the hot water supply schemes can be considered forced decisions, which are dictated by circumstances, for example, savings when creating...
Solve the problem of hot water in an apartment or private house; at the dacha you can heat the water using electric water heaters. There are several types, and in order to decide which water heater is best for your situation, you need to know their advantages, disadvantages and operating features of each type of water heating equipment.
What types of household water heaters are there and how do they differ?
- flow type - heat the water passing through the device;
- storage type - the water in the heater tank is heated;
- flow-storage - have two operating modes;
- liquid
It’s difficult to say which water heater is better. If speak about appearance, then the main thing external difference- this is the size. Cumulative models are large, flow-through models are small. But size is not all that is needed to understand what is best for you. You need to know the advantages and disadvantages of each type of equipment.
Cumulative models
A storage water heater (also known as a boiler) has a capacity of considerable size - from 30 to 200 liters. Inside there is a heating element- Heating element. It may be one or several. The heating elements can be switched on in parallel (they always work simultaneously) or in cascades (they are switched on as needed). When switched on in cascade, there are several heating modes for more efficient energy consumption.
Many more models contain a thermometer to conveniently control the water temperature and a thermostat to maintain the set temperature. The desired temperature is set by turning the thermostat control knob to a certain position.
A storage water heater constantly contains a certain volume of water. It is heated using electric heaters. There are two types:
- heating element ( T ribbed E lectro N heater). Inexpensive classic solution. They are quickly and easily changed, and any specialty store has a wide selection in stock. Disadvantage - it takes a long time to heat the water.
- Spiral heating element. More powerful heaters that quickly heat large volumes of water allow you to accurately maintain the required temperature. But they are more expensive (affects the price of the water heater), and their replacement is also more difficult.
Principle of operation
Regardless of the type of heater installed, the principle of operation of a storage water heater is the same. When the set temperature is reached, the thermostat turns off the power supply and heating stops. Further, the temperature is maintained automatically. When the water cools by 1 degree or cold is added to the tank during consumption, the heating is turned on. As soon as the set temperature is reached (or rather, a degree higher than the set one), heating stops. That's how they work storage water heaters with automation. They are convenient because they do not overheat (if the automation is working properly) and you always have hot water available, which is heated the way you wanted. Such equipment usually has two operating modes - with temperature maintenance or without - in manual mode.
To keep the water temperature as long as possible, insulation is used. It is placed between the walls of the tank and the body. With good thermal insulation, even with hot water, the body remains cold, maybe a little warm. It is clear that if the temperature lasts a long time, the costs of maintaining it are small. Even if you turn off the keep warm function, the water will be hot even after 24 hours.
There are very simple electric water heaters that do not have a thermostat. They are turned on/off by a toggle switch - manually. As you understand, in this case there is a possibility that the water heater will boil and fail (if you forget to turn it off).
There is one more nuance - stepwise activation of heating elements. There are usually two or more of them installed in a housing, and several heating modes are also available. One is more powerful, in which all heaters are turned on, the rest are softer - one or two heating elements can work, depending on their total number. What is this for? In summer you can use heating in a gentle mode - the water will heat up quickly, in winter they usually use all heaters - wait less. In general, you can regulate the heating rate of the boiler in this way. If you have drained all the hot water and need the next batch quickly, turn it on at full power, there is no such need - you can avoid overloading the networks by turning it on at half power.
What materials are tanks made of and features of their maintenance?
Storage water heater tanks are made of stainless and ordinary steel. Regular steel is covered with protective layers of enamel; stainless steel does not need them. From this point of view, it is easy to say which water heater is better - with a stainless steel tank. But it is also more expensive. But the service life of such equipment is much longer - the enamel, even the highest quality, flakes off over time.
To extend the service life of the enameled coating, magnesium anodes are installed in storage steel water heaters. They require periodic replacement - they “melt” during operation, and their condition is monitored by a special sensor with an indicator displayed on the front panel. The status of the indicator monitors the need to replace the anode.
How to choose and which one is better
In most cases, storage water heaters are installed in private houses or in apartments of multi-storey buildings where there is no centralized supply of hot water. Equipment is selected according to tank volume. If you don’t like restrictions, you can calculate it at the rate of 50 liters of hot water per family member. This should be enough. In the tank it heats up to, say, 70°. It is unrealistic to use this, you will dilute it. As a result, there will be 100-150 liters of warm water per person (depending on the temperature of the water in the water supply). This does not take into account the fact that during consumption the water is also heated.
Everything is clear about the material of the tanks: there is a possibility, it is better to take a storage electric water heater with a tank made of of stainless steel. The number of operating modes is not so critical, but it is also a good option, although such models are more complex circuit, are more expensive.
| Name | Tank capacity | Power | Dimensions (W*D*H) | Heating time | Tank | Min/max pressure | Control | Price |
|---|---|---|---|---|---|---|---|---|
| Electrolux EWH 50 Centurio DL | 50 l | 433*255*860 mm | 70 min | stainless steel | 0.7-6 Bar | electronic | 190$ | |
| Ariston ABS VLS Evo PW 100 | 100 l | 2.5 kW | 506*275*1250 mm | 91 min | stainless steel | 0.2-6 Bar | electronic | 185$ |
| Atlantic Vertigo 30 | 30 l | 1 kW | 490*290*601 mm | 46 min | enamel | 0.5-6 Bar | mechanical | 240$ |
| Thermex Flat Plus IF 80 V | 80 l | 1.3 kW | 493*270*1025 mm | 80 min | stainless steel | electronic | 300$ | |
| Zanussi Smalto ZWH/S 50 | 50 l | 2 kW | 470*250*860 mm | 95 min | enamel | 0.75-6 Bar | mechanical | 180$ |
| Gorenje OTG50SLB6 | 50 l | 2 kW | 420*445*690 mm | 115 min | enamel | 0.75-6 Bar | electronic | 155$ |
About which company is better to choose. No one can objectively tell you which water heater is better - people have different needs and requests. But we can draw some conclusions from operating experience. People speak well of storage heaters from the following companies:
- Termex. If we talk about prices for water heaters with a stainless steel tank, then this company has no competitors in terms of price. It’s hard to say about the quality, reviews vary.
- Real. Good storage boilers, the main thing is that you have the consumables in your city.
- OSO. Very good, but expensive.
- Electrolux (AEG). Famous company with stable quality.
Instantaneous water heaters
The instantaneous water heater has more modest dimensions. This is a small box that is attached to the wall. Inside there is also a tank with a heating element, but their dimensions are very miniature, and heating elements usually have the form of a spiral - in order to better heat the passing water.
One of necessary elements flow sensor. It monitors the appearance of water movement in the device (the tap is opened) and sends a command to turn on the heating element. When the tap closes, the flow sensor turns off the power supply.
There is also a thermostat that sets the water temperature. It may be a rotary type with a scale; there are models with an electronic display with push-button or touch controls.
Pressure and non-pressure instantaneous water heaters, their connection
There are two options for instantaneous water heaters - system and individual. System ones cut into cold and hot water risers, also called pressure ones. Several points can be provided at once - for example, a shower, sink and washbasin. There are system instantaneous water heaters 220 V with relatively low power consumption (about 8-9 kW), but they can heat up a small amount of water. There are very powerful units - up to 32 kW, but they are three-phase - 380 V.
There are two broad classes of pressure flowers.
Individual instantaneous water heaters - non-pressure - are connected to cold water. At the outlet they have a flexible hose with a nozzle or, as an option, a faucet for washing. These devices are good for periods when the hot water supply is turned off or as a solution to the problem of hot water in the country.
Please note that the shut-off valve is only for supply and you can only turn off hot water using it. Connecting shut-off valves at the outlet will sooner or later lead to a rupture of the tank in which the water is heated. This happens when the automatic water shutoff does not work. But it is not intended to track water consumption, but only monitors its appearance/disappearance at the inlet. So sooner or later a failure occurs.
When connecting pressure and non-pressure options, grounding is required. In general, it is advisable to run the power supply to such connections using a separate line - high power consumption, the combination of water and electricity is an unsafe combination. Conventional wiring may not hold up. Therefore, a separate line is needed from the one on which the machine and the RCD are located.
Control type
There are two types of control for instantaneous water heaters:
- Hydraulic. When there is a flow sensor at the input (the first photo in the section), the signal from which turns the heating element on/off. The disadvantage of such a system is that it always turns on at the same power. Some models have several power modes, but they must be changed forcibly each time (by pressing buttons).
- Electronic. The operation is controlled by a microprocessor that monitors the state of the device using several sensors. These systems allow you to maintain the required temperature.
Tankless water heaters with hydraulic controls can only add a certain number of degrees to the water temperature. Exactly what depends on the power of the heating element, but on average it is about 20-25°C. This means that in the summer you will get quite warm water- about +40°C, and in winter it will be only slightly warmer than +20°C, since the incoming one is very cold and it is simply not possible to heat the device to higher temperatures.
More powerful models - system ones, with the Sistem prefix - have electronic control and can cope with the task of maintaining the set temperature. Their disadvantage is that they require more power and are expensive. But if you have such an opportunity, the automation will maintain a constant (set by you) temperature at any time of the year. The installation rarely operates at full power, but it is still necessary to pull the power supply line at maximum power and use it to calculate the machine and the RCD.
What are flow heaters made of?
The internal filling can be:
- Made of copper. These models have very good characteristics - they quickly heat the water. Copper has high thermal conductivity and quickly transfers heat.
- Made from stainless steel. Not a bad option, durable (if the water is not hard).
- Made of plastic. The cheapest and not the most durable. Even though special plastic is used, it is better not to buy such flow tubes.
The choice of instantaneous water heater based on this criterion is obvious. If possible, buy one with a copper “filling,” but stainless steel ones also work well.
They draw power with a copper wire with a cross-section of at least 3.5 mm (with a power consumption of up to 7 kW) and 4 mm - up to 12 kW. The machine is selected based on the current consumed; the RCD is taken one step higher with a leakage current of 10 mA. With this connection method and properly functioning grounding there will be no problems.
Features of choice
When choosing an instantaneous water heater, you need to focus on several indicators:
All these parameters should be in the description. Having selected several models, you can then, based on reviews, or based on technical characteristics, decide which water heater is better. If we talk about companies, then German and Italian devices are better in quality. With Chinese ones, it depends on your luck, although many companies have moved production to China. And now most of household appliances has dual “citizenship” - usually written - the homeland of the brand and the place of production. Most of this equipment works reliably, as companies value their name and introduce strict control over product quality.
| Name | Power | Dimensions | Performance | Amount of points | Control type | Operating pressure | Price |
|---|---|---|---|---|---|---|---|
| Thermex System 800 | 8 kW | 270*95*170 mm | 6 l/min | 1-3 | hydraulic | 0.5-6 Bar | 73$ |
| Electrolux Smartfix 2.0 TS (6.5 kW) | 6.5 kW | 270*135*100 mm | 3.7 l/min | 1 | hydraulic | 0.7-6 Bar | 45$ |
| AEG RMC 75 | 7.5 kW | 200*106*360 mm | 1-3 | electronic | 0.5-10 BAR | 230$ | |
| Stiebel Eltron DHM 3 | 3 kW | 190*82*143 mm | 3.7 l/min | 1-3 | hydraulic | 6 Bar | 290$ |
| Evan B1 - 9.45 | 9.45 kW | 260*190*705 mm | 3.83 l/min | 1 | mechanical | 0.49-5.88 Bar | 240$ |
| Electrolux NPX 8 Flow Active | 8.8 kW | 226*88*370 mm | 4.2 l/min | 1-3 | electronic | 0.7-6 Bar | 220$ |
Specific models
There are instantaneous water heaters of non-standard format. The most common is a faucet with an instantaneous water heater. This interesting option for a dacha, for example, but it’s difficult to say how things stand with maintainability - there are not very many users of such devices yet and the operating experience is very small.
Which water heater is better: instantaneous or storage?
Deciding which water heater to buy - a boiler (storage) or a flow-through - is, in principle, not difficult. First of all, the limiting factor is the power consumption: for storage water heaters the maximum is 3-4 kW, for instantaneous water heaters it is pointless to take less than 7-8 kW - they can only heat a very small volume of water. Not everyone has the opportunity to install such powerful equipment.
Secondly, you need to look at whether you will use the electric water heater constantly or only periodically. With occasional use, especially in summer period Instantaneous water heaters are convenient, so open type(individual, which are installed next to the sink). For example this great way heat the water to a comfortable temperature if the sun cannot cope with this task. This is also a way to solve problems in apartments when the hot water supply is turned off for repairs.
For constant and regular use, storage water heaters are more economical and convenient. Modern models They “keep” the temperature for more than a day, so the electricity consumption here will be less rather than more.
Flow-through storage water heaters
This is a combination of the two devices described earlier. They work in two modes. If the water consumption is small, water is supplied from the storage tank; if it increases, flow-through heating is also connected. The equipment is very convenient, but expensive. There aren't many options. This is Stiebel Eltron SHD for 30 liters and 100 liters. Price - $1500-1750.
Bulk water heaters
An excellent solution for a summer cottage or when you are away from home tap water. A tank water heater is a container with a lid in which a heating element is mounted. The container can be made of stainless steel, plastic, ordinary steel coated with enamel. The temperature is regulated by a thermostat. A shower hose is attached to the body.
There are two types of such devices - gravity and with pressure created by a small built-in pump (Alvin EVBO). Gravity tank water heaters must be hung above your head. You can take a shower, but the water flow will be weak. Models with a pump have more pressure, but the tank capacity must be decent and such a model cannot be called a camping one.
The functions here could be:
Bulk water heaters are an original Russian invention and all manufacturers are Russian. There are similar electric water heaters of the following brands:
- Success;
- Alvin Evbo;
- Aquarius;
- Elbet;
- Mr. Heath Summer Resident;
- Fairy tale.
The devices operate on a 220 V network, the power is about 1-2 kW, the price is from $20 to $100, depending on the functionality and material of the tank. Which water heater is best in this category? Stainless with pressure, but these are just the most expensive models.
Every year, traditional energy sources become more expensive, and there is no end in sight to this price race. Meanwhile, the most powerful source of energy, which we see almost every day, “works” completely free of charge. And if humanity has not yet learned how to efficiently obtain energy directly in the form of electricity, then thermal energy Anyone can use the sun, if only they wish!
Indeed, in a sunny area, the luminary sends out approximately 1 kW of energy every hour. It would be a sin not to use such a source at least to heat water. At the same time, the costs of creating and installing a water heating device are minimal. Inventors across the country have long been using a variety of installations for heating water.
Among them there are the simplest and more complex, with automatic control. It all depends on technical preparedness, financial capabilities and, of course, desire.
How do craftsmen get hot water from the sun today?
Create solar heater It’s not at all difficult to do it yourself.
This is the simplest option.
A regular container in the form of a barrel, an old tank, is installed on the roof summer shower or at home, barn and connect through a hose to a regular tap.
If the container is painted black, heating will occur faster.
By the end of the day the water warms up to about 45C. These data are valid for a polyethylene tank of 200-300 liters. It is desirable that it be flat - this increases the heating efficiency.
The only downside is that all the water must be used in the evening, because... in the morning it will become cold.
To “eliminate” this drawback, you will have to insulate the container itself or drain the heated water into an again insulated tank. You can simply feed the water into the boiler and, when it cools down, heat it up. At least some electricity is saved.
Another option is to keep the boiler permanently connected to a tank installed on the roof. Then the water will constantly circulate; it can be used online.
A significant drawback of the system is that it does not work at temperatures below +20C. Therefore, there are other ways to heat water in the off-season.
Solar water heater – collector
This device is considered the most effective. It's all about the material from which the collector is made. Most often this is:
- steel
- brass.
But assembly using metal is labor-intensive (soldering, welding, seals, etc.), so other materials are used. There is a use case polypropylene pipes- they are cheaper. However, their connection can also cause difficulties associated with sealing the joints.
Another disadvantage is significant deformation when heated; this is not so noticeable with metal-plastic pipes, but polypropylene has a high coefficient of thermal expansion. This deficiency can cause leaks in the system.
There is an original and simple solution that involves using a garden hose as a solar collector. The entire assembly process is limited to twisting it into a spiral and placing it in a suitable box.
Excellent flexibility, no connections guarantee no leaks, and the length of the hose allows it to be connected directly to plumbing fixtures without intermediate connections.
The performance of such a system depends on the length of the hose. With a diameter of 2.5 cm and an air temperature of at least +25C, one meter of hose heats 3.5 liters of water to +45C.
It turns out that on a sunny day, by the evening, 10 meters will “give” you 280 liters of hot water. The system operates when the temperature drops to +8C.
How does the water heating process occur?
The sun's rays hit the spiral through the glass and heat the spiral. Heated water becomes a source of long-wave radiation, which is reflected from the glass. Those., Sun rays find themselves in a kind of thermal “trap”.
- To create this heating device, you will need a box where a spiral of black hose will be placed; using other colors will lead to a loss of 5% of the heat. It can be rubber or PVC. Diameter - no less than 1.9 cm, wall thickness no more than 2.5 mm.
- The hose will be connected to the boiler, which should be higher than the spiral. The bottom of the box must be insulated with foam plastic, painted black.
- The box itself is covered with window glass on top (organic is not suitable due to the fact that it does not retain solar radiation well).
- A rubber gasket must be installed between the glass and the box.
Water heater made from PET bottles
The idea is to first create modules (3 bottles each, 4 or 5 are possible), then connect each of them to plastic pipe, which is connected on one side to the source cold water, on the other hand, it produces hot liquid. It is best to use bottles with a capacity of 2-2.5 liters. They must be connected according to the “neck to bottom” principle. 
- To do this, a hole is cut in the bottom for a neck with a diameter of 26 mm. The hole must be located strictly in the center. Therefore, first mark the center by drilling a hole with a 3-6 mm drill.
- To ensure sealing, lubricate the threads on the neck with sealant and leave the structure motionless for 2-3 days. Make a hole in the bottom of the top bottle!
- A module of three bottles is connected in the same way (you can think of some other way) to a plastic pipe, into one end of which cold water enters.
The number of modules can be large. To get 200 liters of hot water you need about 110 bottles - that’s three square meters area.
- Place the resulting block in a box covered with window glass. The tilt angle is from 10 to 30 degrees.
The resulting system is much more efficient than a black barrel of water installed on the roof.
Majority homemade designs heating water by the sun in summer saves 70-80% of the energy spent on heating. In autumn, spring – up to 40%. At the same time, up to 400 kW/h per person is “taken” from the luminary per year! Something to think about.
If you have built a swimming pool at your dacha, then it is important to solve a number of technical problems that are aimed at maintaining this structure. One of them is heating the pool water. There are many methods for heating pool water. In this article we will look at the most common techniques.
Considering that the volume of water in the pool can be large, it will require a lot of energy to heat it. And here it is important not to overdo it by installing too powerful equipment. The temperature of the water affects not only the comfortable stay in it, but also the health of swimmers. For this reason, the temperature indicator is normalized by sanitary rules, along with the content in water chemical substances and microorganisms that can harm the human body.
Based on SanPiN 2.1.2.1188-03 for water quality control in swimming pools, the water temperature should be from 24 to 28 ° C, in health pools - from 26 to 29 ° C, for children under 7 years old - from 30 to 32 ° C, for children over 7 years old - from 29 to 30°C, in hydromassage baths - from 35 to 39°C.
Based on these numbers, you should make sure that the temperature is within the specified recommendations.
As mentioned at the beginning of this article, today there are many ways to warm up the water in a pool, here are some of them:
Does anything influence the choice of technology? Yes, there are several factors that should be taken into account, namely:
- customer preferences;
- volume of water in the pool;
- features of existing communications;
- the amount of water to be heated.
To decide which method is right for you, you should familiarize yourself with each technology in more detail.
One of the most simple ways and relatively inexpensive water heating for small pools - the use of flow-through electric heaters. Their operating principle is that they heat a continuous flow of liquid with a small pressure drop. The dimensions of the equipment are quite compact, so there is no need to additionally equip the technical room. A small booth will be enough.
As for the electric heater itself, its body is made of high-quality stainless steel, titanium or plastic. Heating elements are able to withstand high temperature and this is achieved thanks to the stainless steel alloy.
When choosing this heater, keep in mind that its power must be equal to the volume of water. For example, if you have a shallow pool that is located in a heated room, then most likely a power of 3 kW will be sufficient.
The maximum that instantaneous electric heaters can produce is 18 kW, which is not a lot. Therefore, for a large outdoor pool, you will have to look for an alternative, and in particular if the pool has more than 36 cubic meters of water. Plus, the wiring in the house may not be able to handle such a powerful heater.
So, if we talk about the advantages of this unit, it is quite fast warming up, the ability to control the water temperature, set the automatic control mode, as well as the presence of a sensor that, in the absence of circulation, turns off the heating system. Well, we have already discussed some of the disadvantages, namely low power, high energy consumption and restrictions for houses with weak wiring.
This equipment, unlike the previous one, has more advantages, in particular in terms of energy consumption. Water is heated by connecting a heat exchanger to the heating system of a residential building. In appearance, it resembles a flask with a coil inside. Water moves along it. During circulation, the water is heated to the required temperature. As for the flow of water into this flask, it is regulated by a pump and valve. This valve is controlled by a thermostat. The coil is washed with chilled water from the pool. As you can see, everything is quite simple.
If you install such a water heating system, then the desired temperature is set on the thermostat and the automation will do the rest.
Let's talk about power. It can range from 13 to 200 kW. Accordingly, the choice of power depends, in this case, on the volume of water in the pool. The more it is, the more powerful the equipment is needed. This also affects the duration of water heating.
The principle of the heating system is as follows:
- At the very beginning, the water is heated by a heat exchanger for two days at maximum power.
- This is important, otherwise instrumental collapse may occur, which implies a structural change in the heater body and individual elements.
- After this, the equipment will only need to maintain the water temperature.
The heat exchanger itself is installed between the disinfection system and pumping station. This will completely avoid equipment breakdowns due to the presence of chlorine in the water. If the water has excessive chlorine levels, it is recommended to install a titanium heat exchanger.
As can be seen from this description, the heat exchanger is much more economical, easier to operate, and also has high power. The only negative is the long wait for the water to heat up to the desired temperature.
If you are looking for the most inexhaustible source of energy, then it is, of course, the sun. The main thing is to tame its energy so that you can heat the water in the pool. One of the easiest ways to do this is to install solar panels. Although under open air, the water itself can warm up from the sun’s rays; a completely different picture is in the case of an indoor space. Just the same, solar and solar systems will direct the energy of the sun in the direction you need.
This system consists of separate modules consisting of screens, tubes or cones. Each individual module can heat up to 30 cubic meters of water. If there is more water, then more such modules are needed.
The operating principle of solar panels is described below:
- The collector receives the sun's rays. The collector itself is usually black.
- The collector completely absorbs the rays.
- The collector located inside heats up to 140°C.
- After this it starts circulation pump. It is installed in a storage tank.
- In just a short time, the water in it quickly becomes hot.
- As a result, it can be used for a swimming pool.
More expensive collector models include sensors and three-way automatic valves. Due to this, water is sent to the heat exchanger automatically. Thus, continuous circulation of water is organized.
If you select positive sides This technology means very fast water heating and a simple control system. But if the weather is cloudy, then the efficiency of such a system will decrease significantly.
If you are interested in heating speed and power, then heat pumps are the new and most popular way to heat water. The only thing that scares many buyers is the high price. The principle of operation is as follows (the action resembles the operation of a coolant that uses condensates, etc.):
- The primary source of heat can be industrial or domestic wastewater that has been treated.
- The external pipeline is located underground.
- It is pumped through working fluid using a circulation pump.
- Due to the temperature of the soil, at the outlet this liquid increases in temperature by several degrees.
- Next, the mixture is sent to the heat exchanger.
- In it, the liquid gives up its heat to the refrigerant, which quickly boils. Even a low temperature is enough for it.
- As a result of boiling, steam is formed, which enters the compressor and is compressed to 25 atm.
- During this process the temperature rises to 55°C.
The energy resulting from such actions is sent to the pool to heat the water. The work of the entire system is carried out in a closed circle, according to the principle of circulation. As a result, the power of the heat pump can be used for other household needs. For example, you can provide heat to a house up to 300 m2.
An important advantage is expressed in the high power and speed of heating the water. Free energy sources are also used: earth heat, exhaust gases, Wastewater etc.
We looked at options for heating a pool that are quite expensive. Now we bring to your attention heating options from do-it-yourselfers. The main advantage of these techniques is minimum costs. Consider one of the many options homemade unit for heating the water in the pool.
Firewood has been and remains the most affordable source of fuel. Strange, but there are no industrial units using this fuel. That's why it was invented homemade system heating water. The essence of this idea is that a metal coil is installed inside the firebox. Water is supplied to the inlet using a pump. Through the second hose, the heated water in the coil enters the pool.
The main thing in this method is to select the speed of water movement. Otherwise, the water may either boil or not warm up enough.
Another option is to install a coil inside which a fire is built. A risky method, but it has its place. You can easily use it on a hike. The only thing that needs to be considered is the removal of hot water. To do this, you can use a heat-resistant hose or metal-plastic pipe. In this case, heating will be realized without electricity.
It's one thing to heat water, but without good heat retention, you will have huge energy costs. It is a known fact that a large amount of heat is lost at night. To reduce losses, you can build a canopy over the pool. In this case, the canopy can be:
- Folding.
- Sliding.
- Stationary, etc.
If it is not possible to install a canopy, then you can use a blanket or film that floats on the surface of the water. The film must be straightened at night and removed in the morning, then the water will have enough comfortable temperature, and the cost of heating it will be reduced.
Instead of film, you can use awnings that cover the entire surface of the pool. But the disadvantage of this option is that it will be inconvenient to put even a small awning over the pool alone. However, they are quite effective.
For example, if you have a rectangular pool, then straightening the awning is as easy as shelling pears. On one side, at a distance of 1.5 m, attach light planks. Holding on to them will make it easier for you, even alone, to straighten the awning.
So, we discussed how you can quickly heat the water in the pool. Choose the technology that is available to you. We and our readers will be interested to know how you heat your pool at the dacha, so leave comments at the end of this article.
