Types of heating elevators

Oddly enough, not even all plumbers servicing heating elevators know about heating elevators. multi-story houses. At best, they have an idea that this device is installed in the system. But how it works and what function it performs is not known to everyone, not to mention ordinary people.

Therefore, let's eliminate this gap in knowledge about heating systems and examine this device in more detail.

What is an elevator?

In simple terms, an elevator is a special device related to heating equipment and performs the function of an injection or water-jet pump. No more, no less.

Its main task is to increase the pressure inside the heating system. That is, increase the pumping of coolant through the network, which will lead to an increase in its volume. To make it clearer, let's give a simple example. 5-6 cubic meters of water are taken from the supply water supply as a coolant, and 12-13 cubic meters enter the system where the apartments of the house are located.

How is this possible? And what causes the increase in coolant volume? This phenomenon is based on certain laws of physics. Let's start with the fact that if an elevator is installed in the heating system, it means that this system is connected to central heating networks through which hot water moves under pressure from a large boiler house or thermal power plant.

So the temperature of the water inside the pipeline, especially in extreme cold, reaches +150 C. But how can this be? After all, the boiling point of water is +100 C. This is where one of the laws of physics comes into force. At this temperature, water boils if it is in an open container where there is no pressure. But in the pipeline, water moves under pressure, which is created by the operation of the supply pumps. That's why it doesn't boil.

• Firstly, cast iron does not like large temperature changes. And if cast iron radiators are installed in apartments, they may fail. It's good if they just leak. But they can break, because under the influence of high temperatures, cast iron becomes brittle, like glass.
• Secondly, at this temperature metal elements heating it will not be difficult to get burned.
• Thirdly, for piping heating devices they are now often used plastic pipes. And the maximum that they can withstand is a temperature of +90 C (besides, with such figures, manufacturers guarantee 1 year of operation). This means they will simply melt.

Therefore, the coolant must be cooled. This is where an elevator is needed.

What is the elevator unit used for?

Elevator unit connection diagram

So we come to the question of why elevators are needed in a heating system?

These devices are designed to lower the temperature of the supplied water to the required temperature. And already cooled, it is supplied to the apartment heating system. That is, the coolant is cooled in the elevator. How?

Everything is quite simple. This device consists of a chamber where hot superheated water and water coming from the return circuit of the heating system are mixed. That is, the coolant from the boiler room is mixed with the coolant from the return line of the same house. This is possible without taking a lot hot water, obtain the required volume of coolant at the required temperature.

Are we losing temperature? Yes, we are losing, and the obvious cannot be denied here. But the coolant is supplied through a nozzle, which is much smaller than the diameter of the pipe supplying hot water to the house. The speed in this nozzle is so high due to the pressure inside the pipeline that the coolant is very quickly distributed throughout all risers. Therefore, no matter where the apartment is located, close or far from the distribution center, the temperature in the heating devices will be the same. Uniform distribution is thus ensured 100%.

Do you know what know-it-all plumbers sometimes do? They remove the nozzle and install metal dampers, thereby trying to manually regulate the flow rate of the coolant. It's good if they install it. And in some houses there are no dampers at all, and then the problems begin.

Apartments located closer to the elevator hub will have an African climate. Here, even in the most severe frosts, the windows are always open. And in distant apartments, especially corner ones, people wear felt boots and turn on electric heating devices or gas stove. They criticize everything under the sun, not suspecting that the companies servicing their home are to blame. Here is the result of ignorance and simple incompetence.

How does an elevator work?

The principle of operation of the elevator

The principle of operation of the elevator

Elevator unit It is a fairly large container, somewhat similar to a pot. But this is not the elevator itself, although it is called that. This is a whole unit, which also includes:

• Dirt traps - after all, the water coming from the pipe is not entirely clean.
• Magnetic mesh filters - the unit must ensure a certain purity of the coolant so that batteries and pipes do not become clogged.

Having been purified, the hot water flows through the nozzle into the mixing chamber. Here it moves at high speed, as a result of which water is sucked in from the return circuit, which is connected to the mixing chamber on the side. The process of suction, or injection, occurs spontaneously. It is now clear that by changing the diameter of the nozzle, you can regulate both the volume of coolant supplied and its temperature at the exit from the elevator.

As you understand, for a heating system, an elevator is a pump and a mixer at the same time. And what is important - no electricity.

There is one more point that experts pay attention to - this is the ratio of the pressure inside the supply pipeline and the resistance of the elevator. This ratio should be 7:1. Only this ratio ensures the efficiency of the entire system.

But that's not all there is to efficiency. Pay attention to the fact that the pressure inside the system - and this is the supply and return circuits - must be the same. It is acceptable if it is a little less in the return. But if the difference is significant, for example, in the supply pipeline it is 5.0 kgf/cm2, and in the return pipeline it is below 4.3 kgf/cm2, this means that the pipeline system and heating devices are clogged with dirt.

Connection diagram for an adjustable water-jet elevator

Another possible reason is when carrying out overhaul The pipe diameters were changed downward. That is, the contractor saved money in this way.

Is it possible to regulate the temperature of the coolant? It is possible, and for this it is better to use an adjustable water-jet type elevator.

The design of such a device includes a nozzle, the diameter of which can be changed. Sometimes the adjustment range, and this applies more to foreign analogues, is quite large, which is not so necessary. Domestic elevators have a smaller range shift, but, as practice has shown, this is enough for all occasions.

True, adjustable elevators are rarely installed in residential buildings. It is much more effective to install them in public or production premises. With their help, you can save up to 25% on heating costs just because they allow you to reduce the temperature at night, as well as on weekends and holidays.

Reducing heat losses is a major planning objective central heating. For this purpose, even at the stage of heating the coolant, special conditions for its transportation: high blood pressure, maximum temperature regime. But in order for the heating level to drop to the required level when distributing hot water, an elevator heating unit is installed: the diagrams, operating principles and checks must strictly comply with the standards. Even though it is part of central heating, the average user should know how it works.

Purpose of the elevator unit

Even at the first stages of designing central heating, engineers were faced with the problem of conserving thermal energy due to the length of heating mains. To reduce heat losses, two main methods are used:

• Maximum thermal insulation of the pipe surface;
• Installation of elevator units in buildings.

The operating temperature in the external heating pipes is 150 or 130 degrees. It is prohibited to supply water to consumers at this temperature. That is why an adjustable elevator heating unit was developed. It is designed to mix hot and cold coolant flows in order to optimize its temperature. In addition, the pressure also decreases to an acceptable level.

For normal operation, an automatic elevator heating unit is installed in a pre-prepared room. For residential apartment buildings such is the basement. Installation and further maintenance should only be performed by specialists. Any violation of the operating mode may lead to emergency situations. Installation of such a heating element in private houses is impractical. This is due to the fact that the boilers will not be able to provide the proper operating temperature. Therefore, it is used only for creating branched heating systems with a large length of external heat pipes.

Taking as a basis the operating principle of this elevator heating unit, it is possible to make a similar system for autonomous system. But for this they use two or three way valves with thermostats.

Scheme of operation of the elevator unit

At first glance, the operating principle of the elevator unit of the heating system should be quite complex system. However, in practice, a successful design was developed, which in its own way technical specifications similar to a three-way mixing valve.

Structurally, it consists of the following elements:

• Inlet pipe. Coolant flows through it with high temperature under maximum pressure;
• Return pipe. Necessary for connecting cooled water for further mixing with the hot flow;
• Nozzle. A key element of the diagram of elevator units of the heating system. Hot water enters it under pressure and creates a vacuum in the receiving chamber. As a result, the cooled coolant mixes with the heated one;
• Outlet pipe. Connects to distribution system pipelines for further transportation of liquid to consumers.

In addition to it, the elevator unit of the central heating system must include additional elements. These include mud slides, shut-off valves and sensors. The latter are required for installation, since they help control the parameters of the entire system.

Having understood what an elevator heating unit is, you need to learn more about its types and methods of adjusting operating modes.

After checking the operation of the elevator unit and the entire heating system, you must definitely request an updated passport for the device. It indicates the initial characteristics and the actual ones after control checks.

Types of elevator heating units

This heating diagram for the elevator unit does not reveal the temperature control mechanism. And this is the main way to optimize thermal energy consumption depending on external factors– outside temperature, degree of thermal insulation of the house, and so on. To do this, a special cone-shaped rod is installed in the nozzle. Gears ensure its connection with the valve. By adjusting the position of the rod, the throughput nozzles

Depending on the installed equipment There are two types of adjustable elevator heating units:

• Manual method. The valve rotates traditional method. In this case, the responsible employee must monitor the readings of pressure gauges and thermometers of the system;
• Auto. A servo drive is installed on the valve pin, which is connected to temperature and pressure sensors. Depending on the established indicators, movements of the rod are performed.

A typical elevator unit drawing should include not only the required elements, performance characteristics systems. And for this you need to calculate the parameters. Such work is carried out only by specialized design organizations, as it requires taking into account all factors.

Installing an adjustable elevator unit for heating in combination with a thermal energy consumption meter will save up to 30% of hot coolant consumption.

Installation features and testing

It is worth immediately noting that installation and testing of the operation of the elevator unit and heating system is the prerogative of representatives of the service company. Residents of the house are strictly prohibited from doing this. However, knowledge of the layout of the elevator units of the central heating system is recommended.

During design and installation, the characteristics of the incoming coolant are taken into account. The branching of the network in the house, the number of heating devices and the operating temperature are also taken into account. Any automatic elevator unit for heating consists of two parts.

• Adjusting the intensity of the flow of incoming hot water, as well as measuring its technical indicators - temperature and pressure;
• Directly the mixing unit itself.

The main characteristic is the mixing ratio. This is the ratio of the volumes of hot and cold water. This parameter is the result of precise calculations. It cannot be a constant, since it depends on external factors. The installation must be carried out strictly according to the diagram of the elevator unit of the heating system. After this, fine tuning is done. To reduce the error it is recommended maximum load. This way the water temperature in the return pipe will be minimal. This is a necessary condition for precise control of the automatic valve operation.

After a certain period of time, scheduled checks of the operation of the elevator unit and the heating system as a whole are necessary. The exact procedure depends on the specific scheme. However, you can draw up a general plan that includes the following mandatory procedures:

• Checking the integrity of pipes, shut-off valves and devices, as well as compliance of their parameters with passport data;
• Adjustment of temperature and pressure sensors;
• Determination of pressure loss during coolant passage through the nozzle;
• Calculation of the displacement coefficient. Even for the most accurate heating scheme for an elevator unit, equipment and pipelines wear out over time. This amendment must be taken into account when setting up.

After this work has been completed, the automatic central heating elevator unit must be sealed to prevent tampering.

Cannot be used homemade circuits elevator units for central systems heating. They often do not take into account the most important characteristics, which can not only reduce operational efficiency, but also cause an emergency.

Premises requirements

In the vast majority of cases, mixing units are installed in the basement of the building. To perform its functions, it is necessary to take into account the characteristics of the room - seasonal changes in temperature and humidity.

There are a number of requirements for these indicators, the fulfillment of which is mandatory. This especially applies to elevator units of the central heating system with installed automatic servos:

• The room temperature should not fall below 0°C;
• To prevent the appearance of condensation on the surface of the pipes, an exhaust ventilation system is installed;
• For electrical appliances A separate switchboard must be installed. It is recommended to provide an autonomous power supply in case of an emergency power outage.

However, in fact, it is rare to see adherence to these rules. As a result, even for the most effective drawing of an elevator unit, its practical implementation may differ significantly. That's why they appeared alternative schemes for mixing coolant flows.

In some new apartment buildings, connected to central heating, there is no provision for a heating circuit with an elevator unit. To install it, you need to contact the management company.

Other options for thermal units

Based on the basic principle of operation of the elevator unit of the heating system, alternative methods have been developed to maintain the desired temperature level in the pipes for users. Their difference from traditional scheme consists in the presence of a complex electronic control system.

The first thing the developers of this unit paid attention to was the optimal flow of hot water. Therefore, a thermal energy meter must be installed at the inlet pipe. It makes it possible not only to see the volume of coolant entering the home system, but can also automatically calculate its cost and transmit the data to the management company.

The installed pumps allow you to control the speed of passage of the coolant through the pipes. This is necessary to reduce the error when mixing fluid flows in the nozzle. To do this, temperature sensors are mounted on the inlet and return pipes. If the water heating level is less than the set one, the return pump stops working. To increase the volume of hot coolant, the corresponding pumping equipment is activated.

Any building connected to a centralized heating network (or boiler room) has an elevator unit. The main function of this device is to lower the temperature of the coolant while simultaneously increasing the volume of pumped water in the house system.

Node purpose

Elevator units are installed when superheated water, the temperature of which can exceed 140 ºC, is supplied to a residential building from a thermal power plant or boiler house. It is unacceptable to supply boiling water to apartments, as this can lead to burns and destruction of cast iron radiators. These devices cannot withstand sudden temperature changes. As it turns out, polypropylene pipes, which are so popular today, also do not like high temperatures. And although they are not destroyed by the pressure of hot water in the system, their service life is significantly reduced.

Superheated water supplied from the combined heat and power plant first enters the elevator unit, where it is mixed with cooled water from the return pipeline of the residential building and again supplied to the apartments.

Operating principle and unit diagram

The hot water entering a residential building has a temperature corresponding to the temperature schedule of the combined heat and power plant. Having overcome the valves and dirt filters, the superheated water enters the steel body, and then through the nozzle into the chamber where mixing occurs. The pressure difference pushes a stream of water into the expanded part of the housing, and it connects with the cooled coolant from the heating system of the building.

Superheated coolant, having low pressure, with high speed tends through the nozzle into the mixing chamber, creating a vacuum. As a result, in the chamber behind the jet, the effect of injection (suction) of coolant from the return pipeline occurs. The result of mixing is water at the design temperature, which enters the apartments.

Scheme elevator device gives a detailed idea of functionality this device.

Advantages of water jet elevators

A special feature of the elevator is the simultaneous performance of two tasks: to work as a mixer and as a circulation pump. It is noteworthy that the elevator unit operates without the cost of electricity, since the operating principle of the installation is based on the use of differential pressure at the inlet.

The use of water jets has its advantages:

• simple design;
• low cost;
• reliability;
• no need for electricity.

Using the latest models of elevators equipped with automation, you can significantly save heat. This is achieved by regulating the temperature of the coolant in its outlet area. To achieve this goal, you can lower the temperature in apartments at night or during the day, when most people are at work, study, etc.

The economical elevator unit differs from the conventional version by the presence of an adjustable nozzle. These parts can have different designs and levels of adjustment. The mixing coefficient for a device with adjustable nozzle varies from 2 to 6. As practice has shown, this is quite sufficient for the heating system of a residential building.

Cost of equipment with automatic adjustment significantly higher than the price of conventional elevators. But they are more economical, functional and effective.

Possible problems and malfunctions

Despite the durability of the devices, sometimes the elevator heating unit malfunctions. Hot water and high pressure quickly find weak points and cause breakdowns.

This inevitably happens when individual components have an assembly poor quality, the calculation of the nozzle diameter was carried out incorrectly, and also due to the formation of blockages.

Noise

The heating elevator may create noise when operating. If this is observed, it means that cracks or scuffs have formed in the outlet part of the nozzle during operation.

The reason for the appearance of irregularities lies in the distortions of the nozzle caused by the supply of coolant under high pressure. This happens if the excess pressure is not throttled by the flow regulator.

Temperature mismatch

The quality operation of the elevator can also be questioned when the temperature at the inlet and outlet differs too much from temperature chart. Most likely, the reason for this is the oversized nozzle diameter.

Incorrect water flow

A faulty throttle will result in a change in water flow compared to the design value.

Such a violation can be easily determined by changes in temperature in the incoming and return piping systems. The problem is solved by repairing the flow regulator (throttle).

Faulty structural elements

If the connection diagram of the heating system to the external heating main has an independent form, then the cause of poor-quality operation of the elevator unit can be caused by faulty pumps, water heating units, shut-off and safety valves, all kinds of leaks in pipelines and equipment, and malfunction of regulators.

The main reasons that negatively affect the design and principle of operation of pumps include the destruction of elastic couplings in the connections of the pump and electric motor shafts, wear of ball bearings and destruction of seats for them, the formation of fistulas and cracks in the housing, aging of oil seals. Most of the listed faults can be eliminated by repair.

The problem of fistulas and cracks on the body is solved by replacing it.

Unsatisfactory operation of water heaters occurs when the tightness of the pipes is broken, they are destroyed or the tube bundle sticks together. The solution to the problem is to replace the pipes.

Blockages

Blockages are one of the common causes of poor heat supply. Their formation is associated with dirt entering the system when dirt filters are faulty. Deposits of corrosion products inside pipes also increase the problem.

The level of filter clogging can be determined by the readings of pressure gauges installed before and after the filter. A significant pressure drop will confirm or refute the assumption about the degree of clogging. To clean the filters, it is enough to remove dirt through the drainage devices located in the lower part of the housing.

Any problems with pipelines and heating equipment must be eliminated immediately.

Minor comments that do not affect the operation of the heating system are necessarily recorded in special documentation and are included in the current or capital plan. repair work. Repairs and elimination of defects take place in summer time before the start of the next heating season.

For heating systems in residential premises, there is a standard coolant temperature. In accordance with established norm the temperature of the water that enters the radiators should not exceed +95 degrees. But heating networks can supply coolant whose temperature exceeds this indicator and ranges from 130 to 150 degrees. Therefore, it is necessary to lower the water temperature to the required value. The solution to this problem is assigned to the elevator heating unit.

This is what an elevator for a heating system looks like

The elevator works in this way: the coolant from the main line is supplied to a removable conical nozzle, in which the speed of water movement increases and, as a result, a stream of water from the nozzle enters the mixing chamber, where it mixes with cooled water that enters there through a jumper from the return pipeline.

After mixing the superheated main water and cooled water, the coolant of the required temperature enters the heating system and heating devices. And in order to prevent large particles from entering the elevator, a mud trap is installed in front of the device.

Elevators have become widespread due to their sustainable operation aimed at changing thermal and hydraulic modes in heating networks.

Elevator heating units do not require constant monitoring. Their performance is regulated the right choice nozzle diameter. To select the dimensions, the diameter of the elevator assembly pipes and the diameter of the nozzle, you must contact a design office with the appropriate competence.

Now let's look in more detail at how the elevator heating system works and whether it is possible to do without this device.

Diagram of an elevator heating unit

The elevator assembly diagram for the heating system looks like this.

Here we see that this diagram includes a supply heat pipe (No. 1), as well as a return heat pipe (No. 2), other components of the elevator assembly are valves (No. 3), a water meter (No. 4), mud traps (No. 5), pressure gauges and thermometers numbered 6 and 7, and, of course, the elevator itself (8) and heating devices (9).

Elevator unit diagram

The diagram below shows the simplest basic configuration of an elevator unit. But if necessary, the elevator unit can be supplemented with other elements: regulators, branches of primary and secondary coolants, filters, metering devices, etc.

The principle of operation of the elevator unit in the heating system

The operation of the elevator unit consists of several stages:

1. Water from the main network enters the nozzle, which is narrowed at the outlet, and is accelerated due to the pressure difference.
2. Superheated water comes out of the nozzle with reduced pressure and high speed. As a result, a vacuum is created and water is sucked into the elevator from the return pipeline.
3. The amount of both superheated and reverse cooled water is regulated so that the temperature of the water leaving the elevator unit corresponds to the design value.

We figured out that the elevator unit, located at the inlet to the local heating system, reduces the temperature of the coolant, which is supplied from the central main network to the local heating system, this happens by mixing return water.

Now let's look at what consequences can be expected local sewerage, if the elevator unit is not installed.

Is an elevator needed in a heating system?

The elevator is a water-jet pump, which, due to the pressure difference, increases the pumping of coolant in the internal heating system. That is, it takes a certain amount of water from the main network, dilutes it with cooled return water from the local heating system and sends it again to heating radiators to heat apartments.

Now let's see what can happen to our heating without this the required device. If water above 130 degrees enters the heating system, then the apartments located at the beginning of the heating system will be very hot, and the apartments located a little further away will have a consistently low temperature.

Do not supply water with high temperature (over 130 degrees) to cast iron batteries, which can burst if there is a sharp change in temperature. For polypropylene pipes, which are now widely installed in heating systems, operating water temperatures above 95 degrees are unacceptable. For a short time, polypropylene can withstand temperatures of 100 degrees.

From all this we can conclude that the elevator unit is vital for our heating system.

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As you know, heating is an indispensable system for absolutely any living space. However, not all owners know that very important components of all heat supply systems are mechanisms such as elevator units of the heating system. This equipment plays an important role in the process of heating the coolant, so we should take a closer look at what an elevator heating unit is, as well as some of its characteristics and properties.

The principle of the elevator heating unit

An elevator heating unit is a special mechanism that serves to provide the entire heating system with coolant and for its proper distribution throughout the room. The principle of its operation is as follows: hot water flows to a specific room as a heating source, and at the outlet it comes out moderately cooled.

To equip such a unit, you must first have the following elements:

• pipe system responsible for supply. In this section, the coolant enters the desired room;
• outlet pipes. Here the already cooled water is removed, which is returned back to the boiler room.

For several houses, it is customary to create special heat chambers, in which not only hot water is distributed between buildings, but also special fittings are installed that cut off pipelines. In addition, such chambers are usually equipped with special drainage mechanisms designed to empty the pipes, for example, during repair work. All subsequent activities directly depend on the temperature of the coolant (read: "").

In domestic heating systems, there are several main modes in which boiler rooms operate:

• feed with a parameter of 150° and return of 70°;
• the same characteristics with indicators of 130° and 70°, respectively;
• another option is 95° and 70°.

The mode in which the boiler room operates depends, first of all, on the climatic conditions in a particular region. This means that for less cold areas, 130°/70° will be suitable, while in harsher climates, 150°/70° will be required.

These modes should be taken into account so that the room does not overheat too much and you can stay in it without experiencing any inconvenience.

It should also be noted that boiler units are most efficient when they operate at maximum load. The coolant supplied to a particular living space is subsequently regulated through a mechanism such as an elevator heating unit.

This element consists of the following functional parts:

• temperature sensor displaying parameters of external and internal air;
• servo;
• actuator system equipped with a valve.

Such devices are usually equipped special devices, taking into account thermal energy in each specific room. Thanks to this, it becomes possible to save a significant portion of financial resources. Comparing the elevator in the heating system and similar improved mechanisms, it is worth saying that the latter are more reliable and have a longer service life.

In this case, if the temperature of the coolant does not exceed the parameter of 95°, then the main work is the correct distribution of thermal energy throughout the entire system. Devices serving for these purposes are balancing valves and manifolds.

If the temperature exceeds the above indicator, it should be reduced. It is this function that is performed by the heating system elevator, which supplies chilled water from the return pipeline to the supply pipeline. It is not at all difficult to adjust such a mechanism, but for this it is very important to perform a competent calculation of the heating elevator.

Functional characteristics of the elevator heating unit

As mentioned above, the diagram thermal unit with an elevator provides for cooling the hot coolant to a specified value, after which this water enters the heating radiators in residential areas.

The two main functions that this mechanism performs in the heating system are as follows:

• mixer function;
• circulation function.

In addition, this equipment has several undeniable advantages, including:

• no installation problems due to the simplicity of the design;
• high efficiency indicators;
• no need to connect to the electrical network.

However, such mechanisms also have some negative aspects, among which it is customary to highlight the following:

• the need for high-precision calculations and selection of equipment;
• inability to regulate the temperature of water when draining it;
• In addition, the design of the elevator heating unit requires maintaining the pressure difference between the output and the supply of the heat source (more details: " ").

Today, such designs have become widespread among utility-type networks due to the fact that these devices can withstand any unforeseen changes in temperature and hydraulic conditions. Moreover, their normal functioning does not require constant human presence.

The heating elevator circuit should not be calculated independently; it would be much more correct to entrust this work to qualified craftsmen, since any error in the calculations or connection can cause unpleasant and even dangerous consequences. If you wish, you can study various photo and video materials that describe in detail the entire installation process in order to better understand in the future the principle of operation of such equipment. Read also: "".

Due to the fact that modern technologies are constantly developing, heating systems are constantly equipped with new mechanisms that can improve heating performance. It is worth noting that today there are devices that can provide worthy competition to standard heating units - these are devices equipped with automatic temperature control.

Thanks to this property, the efficiency of energy consumption increases, but the cost of such units is still higher. It is worth noting that these devices cannot function without electricity, and from time to time the power must be very high.

It is impossible to say yet which models are better, since these mechanisms are innovative and they appeared on the market quite recently, but we can say with confidence that they have already become firmly established modern system heat supply and are increasingly used in residential buildings.