Ejector pump (with ejector) for water: operating principle

In what cases is an ejector needed?

Before dealing with the question of what an ejector is, you should find out why a pumping station equipped with it is needed. Essentially, an ejector (or ejector pump) is a device in which the energy of motion of one medium moving at high speed is transferred to another medium. Thus, the operating principle of an ejector pumping station is based on Bernoulli’s law: if a reduced pressure of one medium is created in a narrowing section of the pipeline, this will cause suction into the formed flow of another medium and its transfer from the suction point.

Everyone knows well: the greater the depth of the source, the harder it is to raise water from it to the surface. As a rule, if the depth of the source is more than seven meters, then a conventional surface pump has difficulty performing its functions. Of course, to solve this problem, you can use a more productive submersible pump, but it is better to go the other way and purchase an ejector for a surface-type pumping station, significantly improving the characteristics of the equipment used.

External ejector prepared for immersion into the well

By using a pumping station with an ejector, the liquid pressure in the main pipeline increases, while the energy of the fast flow of the liquid medium flowing through its separate branch is used. Ejectors, as a rule, work in conjunction with jet-type pumps - water-jet, liquid-mercury, steam-mercury and steam-oil.

An ejector for a pumping station is especially relevant if it is necessary to increase the power of an already installed or planned installation of a station with a surface pump. In such cases, the ejector installation allows you to increase the depth of water intake from the reservoir to 20–40 meters.

Difference from injector

Both of these devices are jet devices, that is, for suctioning liquid and gaseous substances.
An ejector is a device in which kinetic energy is transferred from a working medium at high speed to a non-working, that is, passive, medium through their displacement.

Injector - device

, in which gases and liquids are compressed.

The main difference between these devices is the method of transmitting energy to the passive medium. For example, in an injector the supply occurs due to pressure, and in an ejector the supply occurs due to the creation of a self-priming effect.

Almost everywhere you can connect an autonomous water supply to your house. However, the main problem is the depth of groundwater. If the water in the prepared well is at a level of 5-7 meters, then no special problems can be expected, because then you can use almost any type of pump that is suitable in terms of power and performance. If the water is much deeper, then an ejector for pumping stations comes to the rescue.

Operating principle of the ejector

The deeper the water is, the more difficult it is to bring it to the surface. In practice, if the well depth is more than seven meters, the surface pump has difficulty coping with its tasks.

Of course, for very deep wells it is more appropriate to purchase a high-performance submersible pump. But with the help of an ejector, it is possible to improve the performance of a surface pump to an acceptable level and at significantly lower cost.

The ejector is a small but very effective device. This unit has a relatively simple design; you can even make it yourself from scrap materials. The operating principle is based on giving the water flow additional acceleration, which will increase the amount of water coming from the source per unit of time.

This solution is especially convenient for those who are going to install or have already installed a pumping station with a surface pump. The ejector will allow you to increase the depth of water intake to 20-40 meters.

It should also be noted that the purchase of more powerful pumping equipment will lead to a noticeable increase in energy consumption. In this sense, the ejector will bring noticeable benefits.

The ejector for a surface pump consists of the following elements:

• suction chamber;
• mixing unit;
• diffuser;
• narrowed nozzle.

The operation of the device is based on Bernoulli's principle. It states that if the speed of a flow increases, an area of ​​low pressure is created around it. In this way, a rarefaction effect is achieved. Water enters through a nozzle, the diameter of which is smaller than the size of the rest of the structure.

This diagram allows you to get an idea of ​​the design and operating principle of an ejector for a pumping station. The accelerated reverse flow creates an area of ​​low pressure and transfers kinetic energy to the main flow of water

A slight narrowing gives the water flow a noticeable acceleration. Water enters the mixer chamber, creating an area of ​​reduced pressure inside it. Under the influence of this process, a stream of water under higher pressure enters the mixer through the suction chamber.

Water enters the ejector not from the well, but from the pump. Those. The ejector must be installed in such a way that part of the water raised by the pump returns to the ejector through the nozzle. The kinetic energy of this accelerated flow will be constantly transferred to the mass of water that is absorbed from the source.

To create an area of ​​rarefied pressure inside the ejector, use a special fitting, the diameter of which is smaller than the parameters of the suction pipe

This will ensure constant acceleration of the flow. Pumping equipment will require less energy to transport water to the surface. As a result, its efficiency will increase, as will the depth from which water can be drawn.

Part of the water extracted in this way is again sent through the recirculation pipe to the ejector, and the rest enters the water supply system of the house. The presence of an ejector has another “plus”. It sucks up water on its own, which additionally protects the pump from running idle, i.e. from the “dry running” situation, which is dangerous for all surface pumps.

The diagram shows the structure of the external ejector: 1- tee; 2 - fitting; 3 — adapter for water pipe; 4, 5, 6 - corners

To regulate the operation of the ejector, use a regular tap. It is installed on a recirculation pipe, through which water from the pump is directed to the ejector nozzle. Using a tap, the amount of water entering the ejector can be reduced or increased, thereby reducing or increasing the rate of return flow.

Types of ejectors at installation site

When purchasing an ejector to equip a pumping station, keep in mind that such a device can be built-in or external. The design and principle of operation of these two types of ejectors are practically no different; the differences are only in the location of their installation. Built-in ejectors can be placed inside the pump housing or mounted in close proximity to it. The built-in ejection pump has a number of advantages, which include:

• minimum space required for installation;
• good protection of the ejector from contamination;
• there is no need to install additional filters that protect the ejector from insoluble inclusions contained in the pumped liquid.

Centrifugal pump with built-in ejector

Meanwhile, it should be borne in mind that built-in ejectors demonstrate high efficiency if they are used to pump water from sources of shallow depth - up to 10 meters. Another significant disadvantage of pumping stations with built-in ejectors is that they produce quite a lot of noise during their operation, so it is recommended to locate them in a separate room or in a caisson of a water-bearing well. It should also be borne in mind that the design of an ejector of this type involves the use of a more powerful electric motor, which drives the pumping unit itself.

A remote (or external) ejector, as its name suggests, is installed at a certain distance from the pump, and it can be quite large and reach up to fifty meters. Remote-type ejectors, as a rule, are placed directly in the well and connected to the system via a recirculation pipe. A pumping station with a remote ejector also requires the use of a separate storage tank. This tank is necessary to ensure that water is always available for recirculation. The presence of such a tank, in addition, makes it possible to reduce the load on the pump with a remote ejector and reduce the amount of energy required for its operation.

Pump with external ejector

The use of remote-type ejectors, the efficiency of which is slightly lower than that of built-in devices, makes it possible to pump out a liquid medium from wells of considerable depth. In addition, if you make a pumping station with an external ejector, then it can not be placed in the immediate vicinity of the well, but can be mounted at a distance from the water intake source, which can be from 20 to 40 meters

It is important that the location of pumping equipment at such a significant distance from the well will not affect the efficiency of its operation

Advantages, principle of operation and installation details

A surface pump with an external ejector has the following advantages:

• work with great depths up to 50 meters;
• small dimensions and weight of the station;
• convenience of supplying water to the object;
• ability to work in extreme conditions – at temperatures from -20 to + 130 degrees.

Design and principle of operation of the internal ejector

Of course, not every steam ejector pump can boast all of the above advantages. So, some models can work in severe frost conditions, others cannot.

How does the device work?

The steam ejector pump has a fairly simple principle of operation - a small amount of water, which is located in a special tank of the device, is used to assist in drawing in liquid. The operating principle is simple but very effective.

Although, such a system does not have serious performance. But so far no one has invented a new pumping system that can draw liquid from greater depths. That's why a water ejector pump is so popular today.

The ejector for the pump is always lowered to the required depth for water intake, and the pumping system is mounted on the surface for ease of use and adjustment of the water intake system.

Design and types of pumps with ejectors

There are two options for including an ejector in the pump circuit:

• built-in;
• external node.

Functionally, these methods differ. The choice depends on the tasks that will be assigned to the pump. The built-in ejector is located in the pump design, so the suction of liquid and the creation of pressure occur inside the device. In this case, the pump, of course, is also immersed in the well.

On the one hand, this reduces the overall dimensions of the installation. Such a pumping station is capable of working with liquid containing sand and silt. However, the device itself is quite noisy, so it is not installed near a residential building. The maximum water intake depth of such a pump is only about 8 m.

A remote ejector involves equipment of a ground pumping station. The unit itself is placed in the pipeline at depth. A tank is placed on the surface, which facilitates the operation of the pump: it creates pressure and additional vacuum. Among the disadvantages of such a device is the need to lower the second pipe, which can be inconvenient if the well diameter is limited.

The efficiency of a pump with a remote ejector is 30-35% lower than that of a “colleague” with a built-in one. But you can get water from a depth of up to 50 m. And it works much quieter. It is even placed in houses, although not in living rooms.

Attention! The remote ejector, pump and related equipment operate effectively even at a distance of 20-40 m from the well.

Features and principle of operation of the installation

At factories producing wastewater disposal equipment, 2 types of pumping equipment are manufactured - with an internal and external ejector pump.

Devices with an internal ejection device pump out water from shallow (8 m or less) wells, reservoirs and wells.

A feature of such equipment is the presence of a “self-priming” function, as a result of which the water level is regulated, which is below the level of the inlet pipe. In this regard, before turning on the device, it is necessary to fill it with water.

After the device is filled with water and turned on, the impeller of the installation with an internal ejector pump sends water to the inlet of the ejector, thereby forming the necessary jet. It moves through a thin tube and the water pressure becomes faster.

When a pipe is connected to the inlet pipe, water begins to flow into the station.

The water then enters a chamber which sucks up the liquid. At the same time, the water pressure becomes less and the liquid flows through the diffuser to the outlet, slightly increasing the flow speed.

A device that uses an external ejector for a pumping station differs from an internal ejection pump in that it is used only at a depth of 10 m or more.

It is also difficult to install external ejector pumps on these devices. The pipes that connect the pumping devices to each other are installed only in a vertical position. Otherwise, a lot of air will enter the inlet line and it will stop working normally.

The optimal option for using devices with a remote ejector is to install the device at a depth of 20 m. As the lifting height increases, its performance decreases.

As a result, the external pumping device has less efficiency than the internal one.

Types of ejector devices

According to their design and operating principle, ejector pumps can belong to one of the following categories.

Steam

With the help of such ejector devices, gaseous media are pumped out of confined spaces and a rarefied state of air is maintained. Devices operating on this principle have a wide range of applications.

Steam ejector for turbine with oil cooler

Steam jet

In such devices, the energy of a steam jet is used to suck gaseous or liquid media from a confined space. The operating principle of this type of ejector is that steam escaping from the nozzle of the installation at high speed carries with it the transported medium exiting through an annular channel located around the nozzle. Ejector pumping stations of this type are used primarily for rapid pumping of water from the premises of ships for various purposes.

Installation of water heating using a steam jet ejector

Gas

Stations with an ejector of this type, the operating principle of which is based on the fact that the compression of a gas medium, initially under low pressure, occurs due to high-pressure gases, are used in the gas industry. The described process takes place in the mixing chamber, from where the flow of the pumped medium is directed to the diffuser, where it is slowed down, and hence the pressure increases.

Air (gas) ejector for chemical, energy, gas and other industries

With remote ejector

To extract water, such pumps must be lowered deep into a well or borehole. A pump with a remote ejector has two pipes. According to one of them, liquid under a certain pressure is supplied to the ejector. This leads to the development of a kind of suction jet.

A pump with an external ejector is significantly inferior in its characteristics to models with a built-in ejector. It's all about the specifics of the design.

Installation diagram of two types of ejector pumps

Thus, a pump with a remote-type ejector will be “afraid” of contaminated water and air entering the structure. Its efficiency is noticeably lower, but the pump’s remote ejector also has its own significant advantage - it can be located inside a living room.

With built-in ejector

An internal centrifugal ejector pump lifts water using artificially created vacuum.

Due to its design features, an ejector pump is much more expensive than conventional devices of this type, as it is capable of lifting water even from great depths up to 50 meters.

High performance, however, is somewhat compensated for by the high level of noise emitted during operation of the device.

Therefore, ejector pumps are installed exclusively in basements and utility rooms of residential buildings.

A modern steam ejector vacuum electric pump is a good solution for organizing a water supply system in a large enterprise and for irrigating large areas with vegetation.

Models for different states of the transported medium

There are ejectors for specific purposes:

• The name of steam jets speaks for itself. In this case, a stream of steam enters the mixing chamber from the nozzle. It is created at the beginning of the recirculation line on the surface. The hot jet carries a portion of liquid upward. Most often used for pumping water from the bilge of a ship.
• The gas industry uses an ejector to pump out gas that accumulates in a confined space.

• There is an air ejector that uses the Venturi effect. The air passing through the nozzle increases the dynamic pressure, but at the same time reduces the static pressure. A vacuum is created, which supplies the pumped air out.

Steam jet ejector Source bullion.ru

Choice: built-in or external?

Depending on the installation location, there are remote and built-in ejectors. There is no big difference in the design features of these devices, but the location of the ejector still affects in some way both the installation of the pumping station and its operation.

So, built-in ejectors are usually placed inside the pump housing or in close proximity to it. As a result, the ejector takes up minimal space and does not have to be installed separately; it is enough to carry out the usual installation of the pumping station or the pump itself.

In addition, the ejector located in the housing is reliably protected from contamination. Vacuum and reverse water intake are carried out directly in the pump housing. There is no need to install additional filters to protect the ejector from clogging with sludge particles or sand.

A remote ejector for a pumping station is more difficult to install than an internal model, but this option creates a much less noise effect

However, it should be remembered that this model demonstrates maximum efficiency at shallow depths, up to 10 meters. Pumps with a built-in ejector are designed for such relatively shallow sources; their advantage is that they provide excellent incoming water pressure.

As a result, these characteristics are sufficient to use water not only for domestic needs, but also for irrigation or other economic operations. Another problem is the increased noise level, since the vibration of the operating pump is added to the sound effect of water passing through the ejector.

If you decide to install a pump with a built-in ejector, you will have to take special care of sound insulation. It is recommended to install pumps or pumping stations with a built-in ejector outside the house, for example, in a separate building or in a well caisson.

The electric motor for a pump with an ejector must be more powerful than for a similar model without an ejector.

An external or external ejector is installed at a certain distance from the pump, and this distance can be quite significant: 20-40 meters, some experts even consider 50 meters acceptable. Thus, a remote ejector can be placed directly in a water source, for example, in a well.

The external ejector does not so much increase the pump’s performance as it is designed to increase the depth of water intake from the source, which can reach 20-45 m

Of course, the noise from the operation of an ejector installed deep underground will no longer disturb the residents of the house. However, this type of device must be connected to the system using a recirculation pipe through which the water will return to the ejector.

The greater the installation depth of the device, the longer the pipe will have to be lowered into the well or well.

It is better to provide for the presence of another pipe in the well at the design stage of the device. Connecting a remote ejector also involves installing a separate storage tank from which water will be drawn for recirculation.

Such a tank allows you to reduce the load on the surface pump, saving some energy. It is worth noting that the operating efficiency of the external ejector is somewhat lower than that of models built into the pump, however, the ability to significantly increase the intake depth makes one come to terms with this drawback.

When using an external ejector, there is no need to place the pumping station directly near the water source. It can be installed in the basement of a residential building. The distance to the source can vary within 20-40 meters; this will not affect the performance of the pumping equipment.

Ejector pumping station

A pumping station with a built-in ejector is a set of equipment originally designed to perform work under certain conditions. The main parameters that are taken into account when choosing are power and performance. The first characteristic means the ability to maintain pressure in the system, as well as the ability to retain a water column and transmit liquid over a distance through a horizontal pipeline.

The second characteristic is productivity. This is the amount of liquid pumped per unit of time. This parameter cannot be greater than the well flow rate. If we are talking about purchasing a pumping station with a built-in ejector, then the technical documentation indicates the general output characteristics. This means that no additional calculations will have to be made.

The equipment is connected according to the attached instructions. The hoses are attached using clamps included in the kit. The pipeline requires a threaded connection. The main thing is to provide a place for installation so that rain and frost cannot damage the system. For this, a caisson is made or a separate building is built. The canopy is only suitable for a summer house that is not intended for year-round use.

A pressure gauge is installed as additional equipment for a pumping station with an ejector, if this is not provided by the manufacturer. Thanks to this device, you can control the pressure in the pipeline. Naturally, it is installed at the exit of the station. If the well depth is within 15-40 meters, experts recommend installing a surface pump with a remote ejector.

Connection diagram

The best connection scheme involves connecting the station to the ejector only with a vertical pipe. Otherwise, airing is possible, which leads to a decrease in system performance. If this is not possible, you need to take care of shut-off valves to bleed air as necessary.

Device installation features

As already mentioned, installing an ejector built into the pump does not cause any particular problems, since the device is already located in the device body. The surface pump is simply connected to the water supply hose on one side, and also to the water supply system on the other side.

If it is used as part of a pumping station, then the pump is connected to the hydraulic accumulator through a special fitting with five outputs. In addition, the pump will need to be connected to the contacts of the pressure switch to ensure that it turns on and off automatically.

This diagram clearly shows the procedure for connecting a remote ejector to a pumping station, indicating the installation locations of all necessary components.

Before turning on the surface pump, it must be filled with water through the filling hole provided for this purpose. You cannot turn on such equipment without water, it may burn. If the pump is installed correctly, the ejector will operate without interruption.

But the installation of a remote ejector is carried out according to a more complex scheme. First, you will need to install a pipe that will ensure the return flow of water from the storage tank to the ejector. A check valve is installed on the suction section of the ejector. A mesh filter should be placed behind it to protect the device from clogging.

An adjustment valve must be installed on top of the recirculation pipe to regulate the amount of water that is directed to the ejector. This unit is not mandatory, but can significantly improve the situation with water pressure in the house.

The less water is returned to the ejector, the more of it will be left for the home's plumbing system.

The ejector is assembled before operation according to the standard scheme. A mesh filter is connected to the ejector body from below, and a Venturi tube made in the form of a plastic socket is connected to the top through the nozzle (+)

This way you can influence the water pressure in the water supply. If it is insufficient, you should slightly tighten the adjusting valve on the return line.

If the pressure is too high and creates unnecessary stress on the plumbing system, it makes sense to direct more water to the ejector in order to increase the efficiency of the pumping equipment.

Some industrial models of ejectors are already equipped with such an adjustment system. The instructions that come with the device usually describe in detail how to configure the ejector.

Features of connecting an ejector pump

Installing a system with a built-in ejector differs little from installing a conventional pump. Your tasks:

1. Connect the well pipe to the suction port.
2. Equip a pressure line with a hydraulic accumulator and automatic control.

If the ejector is external, then the following should be added to the above steps:

1. Laying another pipeline to ensure recirculation.
2. Connection to the suction port of the ejector of a pipe into which a check valve and coarse filtration fiber are mounted.

Surface pump with built-in ejector
A valve on the recirculation line that regulates the return flow will be useful in case of increased water level at the source. By tightening it, you can reduce the water pressure on the way to the ejector and increase it in the faucet at home. The mechanism is built into some models. In this case, the principle of its operation will be described in detail in the instructions.

If desired, you can assemble the ejector yourself. You will need a fitting, a tee and an adapter with angles:

1. The fitting must fit inside the tee in width and be the same length. If it is less, it is increased with a vinyl chloride tube.
2. The hexagonal part of the fitting is ground to a cone shape with a base that will be slightly smaller in diameter than the external thread.
3. Shorten the external thread up to 4 cycles.

   
   Remote ejector

4. Correct the thread and cut it on the conical element. The final task is that the fitting should easily fit into the tee.
5. Screw the fitting into the tee. The outlet hole can extend beyond the level of the average clearance of the tee by no more than 2 mm. The internal thread of the tee must remain at least 4 cycles.
6. Check the fit of the parts and fix them with sealant.
7. The device is connected to the pipe through an adapter.

A pump with an ejector remains an excellent alternative to submersible devices for lifting water from great depths. At the same time, it has many advantages that make it popular for household use.

Manufacturing an ejector and its connection to pumping equipment

Having understood what an ejector is and having studied the principle of its operation, you will understand that you can make this simple device with your own hands. Why make an ejector with your own hands if you can purchase one without any problems? It's all about saving. Finding drawings from which you can make such a device yourself does not present any particular problems, and to make it you do not need expensive consumables and complex equipment.

How to make an ejector and connect it to the pump? For this purpose you need to prepare the following components:

• female tee;
• union;
• couplings, elbows and other fitting elements.

Components for a homemade ejector

The ejector is manufactured according to the following algorithm.

1. A fitting is screwed into the lower part of the tee, and this is done so that the narrow branch pipe of the latter is inside the tee, but does not protrude from its reverse side. The distance from the end of the narrow branch pipe of the fitting to the upper end of the tee should be about two to three millimeters. If the fitting is too long, then the end of its narrow pipe is ground off; if it is short, then it is extended using a polymer tube.
2. An adapter with an external thread is screwed into the upper part of the tee, which will connect to the suction line of the pump.
3. A bend in the form of an angle is screwed into the lower part of the tee with the fitting already installed, which will connect to the recirculation pipe of the ejector.
4. A bend in the form of an angle is also screwed into the side branch pipe of the tee, to which a pipe supplying water from the well is connected using a collet clamp.
5. Homemade ejector assembly

All threaded connections made during the manufacture of a homemade ejector must be sealed, which is ensured by the use of FUM tape. On the pipe through which water will be drawn from the source, a check valve and a mesh filter should be placed, which will protect the ejector from clogging. For the pipes with which the ejector will be connected to the pump and storage tank, which ensures water recirculation in the system, you can choose products made from both metal-plastic and polyethylene. In the second option, installation does not require collet clamps, but special crimping elements.

After all the required connections are made, the homemade ejector is placed in the well, and the entire pipeline system is filled with water. Only after this can the first start-up of the pumping station be carried out.

Personal assembly of the ejector

To make a simple ejector device, you will need plumbing fittings that are always on hand or commercially available - a tee with internal threads, couplings and bends.

The main element is an unequal tee, into the lower part of which a fitting with an external thread is inserted. When installing the fitting, it is necessary to ensure that it does not reach the upper edge of the tee by 2-3 mm. To do this, if necessary, it is modified by filing or extending with a polyethylene tube. The fitting will play the role of a nozzle, so the vacuum in the tee body and the water pressure at the outlet depend on the accuracy of its installation.

A polyethylene pipe is connected to the top of the tee through an adapter to supply water to the system. On the thread of the lower part, in addition to the fitting, there is an outlet for supplying recirculated water from the pump. To draw water from a well or a well, a side pipe of a tee with a polyethylene tube connected through an outlet is used. Its diameter should be smaller than that of the main passage of the fitting.

As for the dimensions, for the manufacture of an ejector that provides water supply to a small house or cottage, it will be sufficient to use a ¾" tee with a ¾" side fitting and an internal fitting with a diameter of 12 mm.

Pipe connection procedure

To connect to adjacent elements of the system, you can use polyethylene or metal-plastic pipes. The pipe connected to the side pipe with the installed check valve and filter must be long enough to be immersed in the well; it is secured first.

A recirculation pipeline is connected to the lower end of the device with a narrowed fitting, connected to the water tank and necessary to create a return flow.

The upper part of the ejector is connected through a pipeline to the surface pump, and the assembly of the homemade ejector installation is completed.

What should you consider when connecting?

An ejector electric vacuum pump (it does not matter whether it is a pump with a remote ejector or a built-in one) must be installed in compliance with all recommendations (they are in the instructions for a specific device model).

For example, after the outlet pipe it is necessary to install a check valve. It will prevent the unit from idling. The pipe drawing in water must be located at a depth of at least 1 m. The diameter of the well, in this case, should not be less than 12 cm in diameter.

If you purchased an expensive ejector for a pump, you can also modify it - install automation. It will allow you to automate the operation of the system, and can also significantly extend the operational life of your unit.

A surface pump with an external ejector, as well as a pump with an internal ejector, are mounted using two additional manipulations:

1. For recirculation, a special gasket must be mounted on the pipe. It extends from the ejector to the pressure pipeline. The pump ejector is then connected to the suction port of the equipment.
2. The water filter pipe, as well as the return valve, must be mounted in the same way to the suction pipe of the ejector.

   
   Connecting the ejector pump

If necessary, the above-described recirculation system is additionally equipped with a tincture tap. It is necessary if the water in the well is at a level significantly higher than the level for which the equipment is designed.

The water pressure on the ejector can be adjusted by increasing the pressure in the water supply system. There are even devices that have “fine” details for tuning this parameter. Usually this detail is described in detail in the documentation for the unit.

Initial launch and further operation

It is recommended to perform the initial start-up of the pumping station according to the following scheme:

1. Pour water into the pump through the special hole.
2. Turn off the tap through which water flows from the pumping station to the water supply system.
3. Turn on the pump for about 10-20 seconds and turn it off immediately.
4. Open the tap and bleed some of the air from the system.
5. Repeat the cycle of short-term pump on/off in combination with bleeding air until the pipes are filled with water.
6. Turn on the pump again.
7. Wait until the accumulator is filled and the pump automatically turns off.
8. Open any water tap.
9. Wait until the water flows out of the accumulator and the pump turns on automatically.

If water does not flow when starting up a system with an ejector, it is possible that air is somehow leaking into the pipes, or the initial filling with water was not performed correctly. It makes sense to check the presence and condition of the check valve. If it is not there, the water will simply pour into the well, and the pipes will remain empty.

These points should also be taken into account when using a pumping station with an ejector, which is started after long-term storage. It is best to check the check valve, the integrity of the pipes and the tightness of the connections immediately.

The lower pipe of the ejector, through which water is drawn, should be protected from contamination using a coarse strainer (+)

If everything is in order, but water does not flow, you need to check the voltage supplied to the pumping station. If it is too low, the pump simply cannot operate at full capacity. You should establish a normal power supply to the equipment, and the problem will disappear.

If an ejector is needed to improve the water pressure in the system, and not to increase the depth of water intake, you can use the homemade ejector model described above.

But it does not need to be immersed in water; it can be placed in a convenient place near the surface pump. In this case, the ejector will work approximately the same as the built-in industrial production model.

How to make an ejector yourself

When a standard pumping station stops suctioning water during operation due to a decrease in the water surface, it can be lowered by digging a hole in the ground of the required depth - there are no other ways to increase the suction depth. There is no point in making a homemade ejector according to any drawings, purchasing and installing it - the part cannot be connected to a housing that has one inlet for the pressure pipeline instead of the two required for the operation of the ejector unit.

If you purchased an ejector pumping station, but the unit was lost or broken, you can make an ejector with your own hands from parts of plumbing fixtures and fittings.

A similar design diagram is shown in Fig. 8, its main components are:

• Tee (1). The part serves to connect the inlet pipes for two water flows and at the same time serves as a chamber in which they are mixed with the transfer of kinetic energy to the transported one. At the outlet of the tee, instead of a diffuser, an adapter coupling is installed to connect the pressure pipeline.
• Fitting (2). The part replaces the nozzle in the standard model and is designed to speed up the recirculating water flow. When installing it, choose the length of the fitting so that the flow coming out of it is on the central axis of the transported product.
• Angles (6, 7). Necessary for connecting the recirculation pipeline and placing the ejector in a vertical position, angle 7 has a small internal diameter due to the fact that the return flow is always supplied to the ejector through a pipeline of a smaller cross-section than the pressure one.
• Angle (5). Through this part, water from the source enters the ejector; the nut at the end is intended for fastening the water filter.
• Adapter (4). The part is necessary to connect the pressure pipeline entering the pumping station.

Before assembly, grind the hexagonal part of the fitting to a cone-shaped state, shorten it to the required length or lengthen it by cutting a vinyl chloride tube. Afterwards, the entire structure is assembled, first screwing in the fitting, and then the remaining parts, sealing the threaded connections with flax, plumbing thread, and FUM tape.

Rice. 8 Homemade ejector

Water pumping stations for individual water supply with a built-in or remote ejector to increase the suction depth are rarely used in everyday life due to their very low efficiency of about 15%. The purchase of such devices is advisable in cases where the level of the water surface is likely to temporarily drop below the maximum permissible level of 9 m due to various circumstances - large volumes of water intake, drought, frequent siltation of the source with a decrease in the water level.

Using a homemade external option

A built-in ejector is usually purchased at the same time as a pump, but the external model is often made by hand.

It will be useful to consider the creation process and the procedure for connecting such a device. In order to make an ejector, you will need such parts as a tee with internal threaded connections, fittings, fittings, bends, couplings, etc.

Sources

• https://met-all.org/nasosy/ezhektor-chto-eto-takoe-printsip-raboty-ustrojstvo-ezhektornyj-nasos.html
• https://sovet-ingenera.com/vodosnab/nasosy/ezhektor-dlya-nasosnoj-stancii.html
• https://nasosovnet.ru/centr/ezhektornyj-nasos.html
• https://sandizain.ru/na-dache/nasosy/nasos-bytovoj-s-vstroennym-i-vynosnym-ezhektorom.html
• https://VodaSovet.ru/nasos/ezhektor-dlya-nasosnoj-stantsii