The heating elevator is an important element of the system. Scheme of the elevator heating unit

Central heating, despite all its real and imaginary shortcomings, it is still the most common way to heat both multi-apartment residential buildings, and public and industrial ones.

The principle of operation of central heating

The general scheme is quite simple: a boiler house or CHP heats water, supplies it to the main heat pipes, and then to heat points- residential buildings, institutions and so on. When moving through pipes, the water cools somewhat and at the final point its temperature is lower. To compensate for the cooling, the boiler room heats the water to over high value. The amount of heating depends on the temperature outside and temperature graph.

• For example, with a schedule of 130/70 at an outdoor temperature of 0 C, the parameter of the water supplied to the main is 76 degrees. And at -22 C - at least 115. The latter is quite within the framework of physical laws, since the pipes are a closed vessel, and the coolant moves under pressure.

It is obvious that such superheated water cannot be supplied to the system, since an overheating effect occurs. At the same time, the materials of pipelines and radiators are greatly worn out, the surface of the batteries overheats up to the risk of burns, and plastic pipes in principle, they are not designed for coolant temperatures above 90 degrees.

For normal heating, several more conditions must be met.

• First, the pressure and speed of water movement. If it is small, then superheated water is supplied to the nearest apartments, and too cold to the distant ones, especially the corner ones, as a result of which the house is heated unevenly.
• Secondly, for proper heating, a certain amount of coolant is required. The thermal unit receives about 5–6 cubic meters from the main, while the system needs 12–13.

It is to solve all of the above issues that the heating elevator is used. The photo shows a sample.

Heating elevator: functions

This device belongs to the category of heating technology and performs several functions.

• Decrease in water temperature - since the supplied liquid is too hot, it must be cooled before serving. In this case, the feed rate should not be lost. The device mixes the supplied coolant with water from the return pipeline, thereby reducing the temperature and not reducing the speed.

• Creating a coolant volume - thanks to the above-described mixing of the supplied water and the liquid from the return, the volume necessary for normal functioning is obtained.
• Function circulation pump- water is taken from the return flow and the coolant is supplied to the apartments due to the pressure drop in front of the heating elevator. In this case, no electricity is used. The regulation of the temperature of the supplied water and its consumption is carried out by changing the size of the hole in the nozzle.

The principle of operation of the device

The device is a rather large capacity, as it includes a mixing chamber. Dirt traps and magnetic mesh filters are installed in front of the chamber: quality tap water in our cities is never high. The photo shows a diagram of the heating elevator.

Purified water enters the mixing chamber with high speed. Due to rarefaction, water from the return is sucked spontaneously and mixed with superheated water. The coolant through the nozzle is fed into the network. It is clear that the size of the hole in the nozzle determines the water temperature and pressure. Devices are produced with adjustable nozzle and permanent general principle their jobs are the same.

A certain ratio must be observed between the pressure inside the supply pipe and the resistance of the heating elevator: 7 to 1. With other indicators, the operation of the device will be inefficient. The pressure in the supply pipe and the return pipe also matters - it should be almost the same.

Heating elevator with adjustable nozzle

The principle of operation of the device is exactly the same: mixing the coolant and distributing it through the network due to the resulting pressure drop. However, the adjustable nozzle allows you to install different temperature for a certain time of day, for example, and thereby save heat.

• The size of the diameter itself does not change, but an additional mechanism is installed in the adjustable nozzle. Depending on the value indicated on the sensor, the throttle needle moves along the nozzle, reducing or increasing its working section, which will change the size of the hole. The operation of the mechanism requires power supply. In the photo - a heating elevator with an adjustable nozzle.

Public institutions and industrial facilities receive the greatest benefit from the apparatus, since for
For most of them, space heating at night is not necessary - the support of the minimum mode is quite enough. The ability to set a lower temperature at night significantly reduces heat consumption. Savings can reach 20-25%.

In residential apartment buildings a device with an adjustable nozzle is used much less frequently, and in vain: at night, the temperature is + 17-18 C instead of 22-24 C is more comfortable. Reducing the temperature index also reduces heating costs.

Today it is impossible to imagine your life without heating. Even in the last century, the most popular was the oven.

Not many people use it these days. The most. All the air rises and thus the floor is not heated.

Technological progress has come a long way. And now the most profitable and popular is the water heating system. Of course, to ensure comfort in the house, heat is of great importance.

Regardless of whether it is an apartment, or private house. However, it must be remembered that the type of heating depends on the type and category of housing. In private houses, individual heating is installed.

But most apartment dwellers still use centralized heating system which requires no less attention.

Elevator node is one of the main components of the system. However, not many people know what functions it performs. Let's look at its functional purpose.

What is it and what is it used for

Working device in the basement

The easiest way to find out what an elevator node is is to visit the basement of an ordinary multi-storey building.

Among the many details of the heating system, it will not be difficult to find this important component.

Consider a simple circuit. How does heat enter the house? There are two pipelines: supply and return. The first is the supply of hot water to the house. With the help of the second, it already gets into the boiler room cold water from the system.

The thermal chamber supplies hot water to basement Houses. Please note that a shut-off valve must be installed at the entrance.

It can be a simple valve, or ball valves. steel cranes. The temperature of the coolant determines how it will work further. There are three main levels of heat:

• 150/70°C
• 130/70°C
• 95 (90)/70°C

If the temperature of the heat carrier is not higher than 95 ° C, then it remains only to distribute the heat throughout the heating system. This is where a manifold with balancing valves comes in handy.

However, everything becomes not so simple if the temperature of the coolant goes beyond the norm of 95 ° C. Such water cannot be run into the heating structure, so the heating must be reduced. This is precisely the important function of the elevator assembly.

Principle and scheme of work

Scheme and principle of operation

The elevator contributes to the cooling of superheated water to a temperature corresponding to the norm.

Then the coolant supplies it to the heating system of residential premises. At the moment when hot water in the elevator from the supply heat pipeline is mixed with the cooled from the return pipeline, and cooling occurs.

The layout of the elevator allows you to get acquainted with it in more detail. functionality. It is not difficult to understand that it is this part of the heating system that ensures the efficiency of its operation.

It works simultaneously as 2 devices:

• Circulation pump
• Mixer

The design of the elevator is quite simple, but effective. Differs in an acceptable price. It does not need to be connected to work. electricity. However, there are some disadvantages that you need to pay attention to:

• The pressure in the forward and reverse transmission pipelines must be maintained within 0.8-2 bar;
• Outlet temperature cannot be adjusted;
• Each element of the elevator must be accurately calculated.

It is safe to say that the devices are widely used in the municipal heating system.

The efficiency of their work is not affected by fluctuations in the thermal and hydraulic regime in heating networks. In addition, the devices do not require constant monitoring. By selecting the correct nozzle diameter, all adjustments are made.

The main elements of the elevator

The main elements of the node

The main components of the device are:

• jet elevator
• Nozzle
• Vacuum chamber

The elevator heating unit consists of stop valves, control thermometers, manometers. It is also called "elevator piping".

New technical ideas and inventions are rapidly introduced into our lives. Heating is no exception.

The usual elevator units are being replaced by devices that regulate the coolant in automatic mode.

Their cost is much higher, but at the same time, these devices are more economical and energy efficient. In addition, they require a power supply to operate. Sometimes more power is needed. Reliability on the one hand and technical progress- with another.

What will be more important in the end, we will find out over time.

The elevator unit of the heating system is used to connect the house to an external heating network (heat supply source), if necessary, to reduce the temperature of the coolant by mixing water from the return pipeline to it.

Functions and characteristics

At correct installation the elevator unit of the heating system performs circulation and mixing functions. This device has the following advantages:

• Lack of connection to the electrical network.
• Efficiency.
• Simplicity of design.

Disadvantages:

• Inability to control the outlet temperature.
• Accurate calculation and selection is required.
• The differential pressure must be observed between the return and supply pipes.

Elevator unit of the heating system: diagram

The design of this device provides for the presence of the following elements:

• Nozzle.
• Discharge chamber.
• Jet elevator.

Additionally, the elevator unit of the heating system is equipped with pressure gauges, thermometers and shut-off valves.

As an alternative this device equipment can be used automatic regulation temperature. It is more economical, more energy-saving, but it costs much more. And most importantly, this equipment is not able to work in the absence of electricity.

For this reason, the installation of an elevator is relevant today. It is characterized by a series undeniable advantages, and it will be used by utilities for a long time to come.

The role of the elevator node

Heating domestic apartment buildings carried out by a centralized heating system. For this purpose, in small and big cities small thermal power plants and boiler houses are being built. Each of these objects generates heat for several houses or neighborhoods. The disadvantage of such a system is a significant loss of heat.

If the path of the coolant is too long, it is impossible to control the temperature of the transported liquid. For this reason, every house must be equipped with an elevator unit. This will solve many problems: it will significantly reduce heat consumption, prevent accidents that may occur as a result of a blackout or equipment failure.

This issue becomes especially relevant in the autumn and spring periods of the year. The heat carrier is heated in accordance with established standards, but its temperature depends on the outside air temperature.

Thus, more hot coolant. It is for this reason that the elevator assembly of the system is so necessary. central heating. It will dilute the superheated coolant cold water and thereby compensates for heat loss.

Operating principle

The elevator unit of the heating system functions as follows:

• From the main network, the coolant is directed to the nozzle narrowed at the outlet, and then, due to the pressure difference, it is accelerated.
• The superheated coolant exits the nozzle at an increased speed and with reduced pressure. This creates a vacuum and suction of liquid into the elevator from the return pipeline.
• The amount of superheated and cooled return heat carrier must be regulated in such a way that the temperature of the liquid leaving the elevator corresponds to the design value.

Elevator unit of the heating system: dimensions

Kinds

There are two types of these devices:

• Elevators that are not amenable to regulation.
• Elevators, the regulation of which is carried out by means of an electric drive.

In the process of installing any of them, it is very important to maintain tightness. This equipment is installed in a heating system that is already in operation. Therefore, before installation, it is recommended to study the place where the subsequent placement of this equipment is planned. This type it is recommended to entrust the work to specialists who are able to understand the scheme, as well as develop drawings and perform calculations.

For a heating system in residential premises, there is a norm for the temperature of the coolant. In accordance with established norm the temperature of the water that enters the radiators should not be more than +95 degrees. But a heat carrier can be supplied through the mains of heating networks, the temperature of which exceeds this indicator and is in the range from 130 to 150 degrees. Therefore, it is necessary to lower the water temperature to the desired value. The solution of this problem is entrusted to the elevator heating unit.

it looks like an elevator for a heating system

The elevator works in this way: the coolant from the main is fed into a removable cone nozzle, in which the speed of water movement increases and as a result, the water jet from the nozzle enters the mixing chamber, where it mixes with chilled water that enters there through a jumper from the return pipeline.

After mixing the superheated main water and chilled 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 sump is installed in front of the device.

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

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

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

Scheme of the elevator heating unit

The scheme of the elevator unit for the heating system looks like this.

Here we see that this scheme 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 collectors (No. 5), pressure gauges and thermometers numbered 6 and 7, and, of course, the elevator itself (8) and heating devices (9).

Scheme of the elevator node

The diagram below shows the simplest basic configuration of an elevator assembly. 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, narrowed at the outlet, and is accelerated due to the pressure drop.
2. Superheated water exits the nozzle at low pressure and at 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 return chilled water is regulated so that the temperature of the water that leaves 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 that is supplied from the central main network to the local heating system, this happens by mixing return water.

Now consider what consequences can be expected local sewerage if the elevator assembly is not installed.

Do I need an elevator in the heating system?

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

Now let's see what can happen to our heating without it. desired device. If water is supplied to the heating system above 130 degrees, then it will be very hot in the apartments that are located at the beginning of the heating system, and a stable low temperature will be established in the apartments that are located a little further.

Water cannot be supplied from high temperature(over 130 degrees) in cast iron batteries, which can burst with a sharp temperature drop. For polypropylene pipes, which are now universally installed in heating systems, working temperature water above 95 degrees is invalid. For a short time, polypropylene can withstand temperatures of 100 degrees.

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

In this article, we have to find out what an elevator is in a heating system and how it works. In addition to functions, we will study the operating modes of the elevator assembly and how to adjust it. So, let's go.

What it is

Functions

talking in simple terms, elevator heating units are a kind of buffer between the heating main and house engineering systems.

They combine several functions:

• The pressure drop between the lines of the route (3-4 atmospheres) is converted into 0.2 necessary for the operation of the heating circuit.
• Used to start or stop heating and hot water systems.
• Allows you to switch between different modes of operation of the DHW system.

To clarify: the temperature of the water in the taps should not exceed 90-95 degrees.
In summer, when the water temperature in the supply line does not exceed 50-55 C, the DHW is supplied from this particular line.
At the peak of cold weather, hot water supply has to be switched to the return pipeline.

Elements

The simplest scheme of the elevator heating unit includes:

1. A pair of inlet valves on the supply and return threads. The supply is always higher than the return.
2. A couple of house valves that cut off the elevator unit from the heating system.
3. Gryazeviki on the supply and, less often, on the return.

In the photo - a mud trap that prevents sand and scale from entering the heating circuit.

1. Vents in the heating circuit, allowing to completely drain it or bypass the system for discharge, expelling a significant part of the air from it at startup. Discharges are considered good form to bring to the sewer.
2. Control valves to measure the temperature and pressure of the supply, return and mixture.
3. Finally, the actual water jet elevator - equipped with a nozzle inside.

How does it work elevator system heating? The principle of its work is based on Bernoulli's law, which states that static pressure in the flow is inversely proportional to its speed.

More hot and under more high pressure water from the supply pipeline is injected through the nozzle into the elevator bell and creates there, paradoxically as it sounds, a rarefaction zone that draws part of the water from the return pipeline into the repeated circulation cycle through suction.

This ensures:

• High coolant flow through the circuit with a minimum flow from the route.
• Equalization of temperatures close to the elevator and heaters far from it.

How are the pressures measured during heating season? Here are some typical settings.

The temperatures in the route and after the elevator are subject to the so-called temperature graph, the determining factor in which is the street temperature. The maximum value for the supply line of the route is 150 degrees: with further heating, the water will boil, despite overpressure. Maximum temperature mixtures - 95 C for two-pipe and 105 for single-pipe systems.

In addition to the listed elements, the heating system elevator may include hot water tie-ins.

Two basic configurations are possible.

1. In houses built before the end of the 70s, the hot water supply is fed through one tie-in to the supply and one to the return.
2. In newer houses, there are two tie-ins on each thread. A retaining washer with a diameter of 1-2 mm larger than the diameter of the nozzle is placed between the tie-ins. It provides a difference sufficient to ensure that when the hot water supply is turned on according to the “from supply to supply” and “from return to return” schemes, water continuously circulates through the twin risers and heated towel rails.

Areas of responsibility

What is an elevator heating unit - we sort of figured it out.

And who is responsible for it?

• The section of the route inside the house to the flanges of the inlet valves is the area of ​​responsibility of the organization transporting heat (heat networks).
• Everything after the inlet valves, and the valves themselves, is the area of ​​responsibility of the housing organization.

However: the selection of the heating elevator by number (size), the calculation of the diameter of the nozzle and retaining washers are carried out by heating networks.
Residents only provide installation and dismantling.

The control

The controlling organization is again heating systems.

What exactly do they control?

• Several times during the winter control measurements temperatures and pressures of supply, return and mixture. In case of deviations from the temperature graph, the calculation of the heating elevator is carried out again with a bore or a decrease in the diameter of the nozzle. Of course, this should not be done at the peak of cold weather: at -40 on the street, driveway heating can catch ice within an hour after the circulation stops.
• In preparation for the heating season, the condition of the valves is checked. The check is extremely simple: all valves in the assembly are closed, after which any control valve is opened. If water comes from it, you need to look for a malfunction; in addition, in any position of the valves, they should not have leaks through the stuffing boxes.
• Finally, at the end of the heating season, the elevators in the heating system, along with the system itself, are temperature tested. When the DHW supply is turned off, the coolant heats up to maximum values.

Control

Here is the procedure for performing some operations related to the operation of the elevator.

Heating start

If the system is full, you just need to open the house valves - and the circulation will begin.

The instructions for starting the reset system are somewhat more complicated.

1. The return vent opens and the supply vent closes.
2. Slowly (to avoid water hammer) the upper house valve opens.
3. After clean, air-free water flows into the discharge, it closes, after which the lower house valve opens.

Useful: if there are modern ball valves on the risers, the direction of the circuit to discharge does not matter.
But for screw fast countercurrent, the valves can be torn off, after which the locksmith will have a long and painful search for the reasons for stopping the circulation in the risers.

Work without a nozzle

At a catastrophically low return temperature at the peak of cold weather, the operation of the elevator without a nozzle is practiced. The coolant enters the system from the route, and not the mixture. The suction is suppressed with a steel pancake.

Differential adjustment

With an overestimated return flow and the impossibility of prompt replacement of the nozzle, adjustment of the differential with a valve is practiced.

How to do it yourself?

1. The supply pressure is measured, after which the pressure gauge is placed on the return line.
2. The inlet valve on the return line is completely closed and gradually opens with pressure control on the pressure gauge. If you just close the valve, its cheeks may not completely fall down the stem and slide down later. The price of the wrong course of action is guaranteed defrosted driveway heating.

At a time, no more than 0.2 atmospheres of the difference should be removed. Re-measurement of the return temperature is carried out in a day, when all values ​​are stabilized.

Conclusion

We hope that our material will help the reader understand the scheme of work and the procedure for adjusting the elevator assembly. Normally, Additional information the attached video will bring to his attention. Good luck!