Scheme of the elevator node of the heating system in an apartment building. The principle of operation of the heating elevator with an adjustable nozzle

The heating system is one of the most important life support systems at home. Each house uses a certain heating system, but not every user knows what an elevator heating unit is and how it works, its purpose and the possibilities that are provided with its use.

Electric heating elevator

Operating principle

The best example that will show the heating elevator working principle will be multi-storey building. It's in the basement high-rise building among all the elements you can find an elevator.

First of all, let's consider which drawing has an elevator heating unit in this case. There are two pipelines here: supply (it is through it hot water goes to the house) and reverse (cooled water returns to the boiler room).

Scheme elevator node heating

From the thermal chamber, water enters the basement of the house; there must be shutoff valves at the entrance. Usually these are valves, but sometimes in those systems that are more thought out, they put Ball Valves of steel.

As the standards show, there are several thermal modes in boiler rooms:

150/70 degrees;
130/70 degrees;
95(90)/70 degrees.

When the water heats up to a temperature not exceeding 95 degrees, the heat will be distributed throughout the heating system using a collector. But at temperatures above normal - above 95 degrees, everything becomes much more complicated. Water at this temperature cannot be supplied, so it must be reduced. This is precisely the function of the elevator heating unit. We also note that cooling water in this way is the easiest and cheapest way.

Purpose and characteristics

The heating elevator cools the superheated water to the calculated temperature, after which the prepared water enters the heating appliances that are located in residential areas. Water cooling occurs at the moment when hot water from the supply pipeline is mixed in the elevator with cooled water from the return.

The heating elevator diagram clearly shows that this unit contributes to an increase in the efficiency of the entire heating system building. It is entrusted with two functions at once - a mixer and circulation pump. Such a node is inexpensive, it does not require electricity. But the elevator has several disadvantages:

The pressure drop between the supply and return pipelines should be at the level of 0.8-2 bar.
The outlet temperature cannot be adjusted.
There must be an accurate calculation for each component of the elevator.

Elevators are widely applicable in municipal thermal economy, as they are stable in operation when the thermal and hydraulic regime changes in thermal networks. The heating elevator does not need to be constantly monitored, all regulation consists in choosing correct diameter nozzles.

The heating elevator consists of three elements - a jet elevator, a nozzle and a rarefaction chamber. There is also such a thing as elevator strapping. The necessary shut-off valves, control thermometers and pressure gauges should be used here.

To date, you can find elevator nodes of the heating system, which can electric drive adjust nozzle diameter. So, it will be possible to automatically regulate the temperature of the heat carrier.

The selection of this type of heating elevator is due to the fact that here the mixing ratio varies from 2 to 5, in comparison with conventional elevators without nozzle control, this indicator remains unchanged. So, in the process of using elevators with an adjustable nozzle, you can slightly reduce heating costs.

The design of this type of elevators incorporates a regulating actuator that ensures the stability of the heating system at low flow rates of network water. In the cone-shaped nozzle of the elevator system, there is a regulating throttle needle and a guiding device that spins the water jet and plays the role of a throttle needle casing.

This mechanism has a motorized or manually rotated toothed roller. It is designed to move the throttle needle in the longitudinal direction of the nozzle, changing its effective cross section, after which the water flow is regulated. So, it is possible to increase the consumption of network water from the calculated indicator by 10-20%, or reduce it almost to the complete closure of the nozzle. Reducing the nozzle cross section can lead to an increase in the flow rate of the network water and the mixing ratio. So the temperature of the water drops.

Malfunctions of heating elevators

The scheme of the elevator heating unit may have malfunctions that are caused by a breakdown of the elevator itself (clogging, an increase in the diameter of the nozzle), clogging of the mud collectors, breakdown of fittings, violations of the settings of the regulators.

The failure of such an element as a heating elevator device can be seen by how temperature drops appear before and after the elevator. If the difference is large, then the elevator is faulty, if the difference is insignificant, then it may be clogged or the nozzle diameter is increased. In any case, the diagnosis of a breakdown and its elimination should be carried out only by a specialist!

If the elevator nozzle becomes clogged, it is removed and cleaned. If the calculated diameter of the nozzle increases due to corrosion or arbitrary drilling, then the scheme of the elevator heating unit and the heating system as a whole will come into a state of imbalance.

Appliances that are installed on the lower floors will overheat, and those on the upper floors will receive less heat. Such a malfunction, which the operation of the heating elevator undergoes, is eliminated by replacing it with a new nozzle with a design diameter.

Clogging of the sump in a device such as an elevator in a heating system can be determined by how the pressure difference has increased, controlled by pressure gauges before and after the sump. Such clogging is removed by dumping dirt through the drain valves of the sump, which are located in its lower part. If the blockage is not removed in this way, then the sump is disassembled and cleaned from the inside.

Centralized heating, despite all its real and imaginary shortcomings, 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 a higher value. The amount of heating depends on the temperature outside and temperature chart.

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.
The function of the circulation pump is the intake of water from the return and the supply of coolant to the apartments is carried out 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 mesh magnetic filters are installed in front of the chamber: the quality of tap water in our cities is never high. The photo shows a diagram of the heating elevator.

Purified water enters the mixing chamber at 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 available with an adjustable nozzle and a constant, 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 set different temperatures for certain times of the day, for example, and thus 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.

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.

Flaws:

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 with automatic temperature control can be used. 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 has a number of 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, small thermal power plants and boiler houses are being built in small and large cities. 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, in the nearest houses, in comparison with those located further away, a hotter coolant enters. 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 with 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

Number	Coolant consumption	Neck diameter	Weight	Dimensions
Number	Coolant consumption	Neck diameter	Weight	L	l1	l2	h	flange 1	flange 2
0	0.1-0.4 t/h	10mm	6.4kg	256mm	85mm	81mm	140mm	25mm	32mm
1	0.5-1 t/h	15mm	8.1kg	425mm	110mm	90mm	110mm	40mm	50mm
2	1-2 t/hour	20mm	8.1kg	425mm	100mm	90mm	110mm	40mm	50mm
3	1-3 t/hour	25mm	12.5kg	625mm	145mm	135mm	155mm	50mm	80mm
4	3-5 t/hour	30mm	12.5kg	625mm	135mm	135mm	155mm	50mm	80mm
5	5-10 t/h	35mm	13kg	625mm	125mm	135mm	155mm	50mm	80mm
6	10-15 t/h	47mm	18kg	720mm	175mm	180mm	175mm	80mm	100mm
7	15-25 t/h	59mm	18.5kg	720mm	155mm	180mm	175mm	80mm	100mm

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. It is recommended to entrust this type of work to specialists who are able to understand the scheme, as well as develop drawings and perform calculations.

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 words, 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 regimes 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:

A pair of inlet valves on the supply and return threads. The supply is always higher than the return.
A couple of house valves that cut off the elevator unit from the heating system.
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.

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. Dumps are considered good tone discharge into the sewer.
Control valves to measure the temperature and pressure of the supply, return and mixture.
Finally, the actual water jet elevator - equipped with a nozzle inside.

How does it work elevator system heating? The principle of its operation is based on Bernoulli's law, which states that the 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 socket 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.

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.
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 drop 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.

Control

The controlling organization is again heating networks.

What exactly do they control?

Several times during the winter, control measurements of the temperatures and pressures of the supply, return and mixture are carried out.. 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 is checked stop valves . 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.

Several harder instruction to start the reset system.

The return vent opens and the supply vent closes.
Slowly (to avoid water hammer) the upper house valve opens.
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?

The supply pressure is measured, after which the pressure gauge is placed on the return line.
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. As usual, the attached video will offer additional information to his attention. Good luck!