Overview of the water pump "Gnome": device, characteristics and features of operation

Looking closely at the domestic pump, choosing a unit for pumping dirty water? Pumping equipment must be functional, reliable and easy to operate, right?

You doubt the real capabilities and technical characteristics of an inexpensive device? We will help you find out all your questions - the article discusses in detail the “Gnome” water pump designed for pumping contaminated and clean water.

Performance characteristics, marking, pluses and minuses of the equipment, as well as operating features are given. The material in the article is supplemented by visual photos and a video review of the “Gnome” brand pump.

Specifications and Labeling

Electric pumps under the brand name “Gnome” are produced by Russian and Belarusian manufacturers. Pumps of the “Gnome” line belong to the class of single-stage vertical submersible pumps of a monoblock design.

They are designed for pumping drainage and groundwater containing by mass no more than 10% of solid mechanical particles, the density of which does not exceed 2.5 thousand kg / m³.

Pumping of fractions no more than 5 mm is allowed. The temperature of the pumped liquid is up to +35 ºС, and for models with the marking “Tr” - up to +60 ºС. The unit is used in everyday life, industry, housing and communal services, agriculture.

More device and features of drainage pumps considered in our other article.

The body of the submersible electric pump is made of plastic, cast iron or steel. Impellers and engine cover are made of cast iron.

The equipment is produced with different types of motor, depending on which the ability to be supplied from a household power supply with a voltage of 220 V or from a three-phase industrial with a voltage of 380 V and a frequency of 50 Hz is determined.

Manufacturers of centrifugal pumps Gnome offer a wide range of products with different technical characteristics, so you can choose a model with the necessary parameters

The electric pump comes with a 10 m long power cord for three-phase or a cord and a starter for a single-phase power supply. Most manufacturers, for a fee and at the request of the buyer, include an automatic machine to protect the motor working from the 380 V network.

Such technical characteristics as power, power supply parameters, productivity (pumping speed), maximum head, as well as the dimensions and weight of the equipment depend on the specific model.

You can compare the technical characteristics of the “Gnome” pump models using the table:

The technical characteristics of the pumps are indicated in the nominal mode and can differ by no more than ten percent for pressure indicators and no more than three percent for efficiency

All pumps manufactured under the brand “Gnome” are marked. Knowing what lies behind the numbers and notation, you can easily understand what characteristics and features the pump has.

The word “Gnome" itself is an abbreviation and is deciphered as follows:

• G - dirty water;
• N - pump;
• ABOUT - single-stage;
• M - monoblock.

The first digit in the marking indicates productivity in m³/ hour, the second is the head in meters. For example, “Gnome 10-10 Tr” is a pump with a capacity of 10 m3 / h and a pressure of 10 m.

The designation “Tr” indicates that this equipment can pump water with temperatures up to +60 C. The letter “D” means that the equipment is equipped with a float switch (level sensor).

The main advantage of the Gnome pump series is its simplicity. To disassemble for cleaning and assemble the unit without problems, you can do it yourself

Pumps marked with the abbreviation “Ex” belong to the explosion-proof group. Such units are capable of pumping water with impurities of petroleum products, which contain no more than 3% sulfur.

In emergency cases, the pump can be used to work in an environment containing up to 100% crude oil.

Overview of manufacturers and model range

Today, three Russian plants are engaged in the production of Gnom submersible pumps - the Odintsovo Pumping Plant, the oil refinery No. 1 and Livgidromash, and one Belarusian - Polesyeelektromash.

The equipment of the Odintsovo Pumping Plant is considered to be of the highest quality. Units of this release are distinguished by high build quality and low reject rate. The disadvantages of these products include the high cost of the pumps in comparison with analogues and expensive repairs.

You may also be interested in information about pump repair, discussed in detail in our other article.

The reliability and durability of the electric pump depends on the materials that manufacturers use to produce products, as well as on the build quality

Pumps manufactured by MNZ No. 1 are distinguished by a lower cost, but have a number of disadvantages: low build quality, manufacture of some of the leading parts made of plastic, and high sensitivity to fluctuations in the power supply network.

The products of Polesieelectromash and Livhydromash are not often found on the Russian market, but experts agree that this equipment meets high requirements.

The variety of the model range of electric pumps "Gnome" without difficulty will allow you to choose the best equipment for the needs of the consumer.

All existing models can be conditionally divided into four groups:

1. Household pumps. Used for pumping dirty water in private households. This group includes pumps of the Mini - Gnome 7-7 and 7-7D series, as well as models with a capacity of up to 16 m³/ h When it comes to buying a pump for domestic use, this refers to equipment of this particular group.
2. Powerful pumps. They are used in industry, construction, utilities. Productivity - from 25 to 600 m³/ h These pumps can be controlled using the control station, which is purchased separately and installed by installers.
3. Explosion proof pumps. Involved in the oil and gas industry, energy and chemical industries. Pumps are capable of handling explosive liquids. The cost of such equipment is very high.
4. Self-cooled pumps. Operated both with full and partial immersion. The peculiarity of these pumps is the presence of a special casing design, which is called the “cooling jacket”.

The most widely used models are the Gnome 10-10 and 10-10D, produced for operation from a single-phase power supply network and used in the field of private construction, in cottages and suburban areas.

High-performance pumps “Gnome” are used in construction for pumping flooded pits, the pump is installed at the bottom and gradually pumps out dirty water

Universal unit “Gnome”

Electric pumps "Gnome" are rightly called universal. The simplicity of construction and operation, as well as maintainability and unpretentiousness in maintenance made these pumps very popular.

They are used in a wide variety of industries to perform a wide range of tasks.

Private users usually use the “Dwarf” to:

• pumping flood waters from basements and flooded areas;
• drainage of construction pits, trenches, pools;
• groundwater drainage from suburban areas and agricultural lands;
• disposal of water used by household appliances in the absence of a central sewage system;
• fluid pumping in autonomous pumping stations and treatment facilities;
• purification of silted wells;
• supply of clean water from well mines.

It should be remembered that the pumps “Gnome” cannot be used for pumping fecal effluents! For these purposes, it is better to look at specialized equipment. In another our article, types of fecal pumps.

Do you need a pump for a cesspool and you do not know which one is better to choose? Then the information discussed in the article may be useful to you: The fecal pump for a cesspool: we understand which unit is better and why.

In case of pumping water contaminated with oil products or crude oil, the “Gnome” can work no more than 5 hours.

A dwarf can pump liquids whose viscosity does not exceed 1100 kg / m³. The unit is capable of transporting mixtures and water with solid inclusions up to 5 mm in size and a percentage of contaminants of not more than 10% of the weight of the pumped medium

Device and principle of operation

The design of the “Gnome” electric pumps is a monoblock, which consists of two main parts: the pump component and the electric motor.

The pump part includes:

• Working wheel;
• challenge;
• pump housing.

For pumping liquids with a large number of inclusions, as well as with cement or clay suspension, the lower part of the housing is equipped with a filter mesh.

The gnome is a monoblock uniting two functional compartments: the pump and engine parts. The engine is sealed with a mechanical seal.

The “Gnome” pump is equipped with an asynchronous type electric motor, which consists of a stator, a rotor, a bearing system and a cover. The function of cooling and lubricating the bearings is assigned to the oil that fills the engine cavity.

At the top of the motor there is an elastic rubber cuff that compensates for the expansion of the cooling medium in case of heating. The electric motor itself is cooled directly by underground water during the pumping process.

The rotor speed for all models of the “Dwarves” is 3000 rpm. Thermal fuses are built into the stator, which suppress the operation of the unit during the period of overheating.

If the pump was interrupted by them due to excess temperature, the pump should be disconnected from the mains and wait for it to cool.

Impellers and other casing parts of the submersible electric pump are made of cast iron, the casing and the cover are made of high-quality plastic

The pump is started using a starter located on the power cord. The equipment is equipped with a capacitor and a circuit breaker that protects the motor from overload.

Before starting work, the pump unit must be fully or partially (models with a “cooling jacket”) immersed in water. Work on the “dry” should not exceed 15 minutes

The principle of operation of the pumps “Gnome” is based on the use of centrifugal force, which is created by the impeller. After switching on, water is sucked into it through the filtering net, then it moves to the outlet through the channels and is pushed into the discharge pipe.

Preparing the pump for operation

Before starting the installation of the pump, it is necessary to carry out an external inspection for mechanical damage to the housing and the power cable. It also requires checking for oil in the oil chamber.

To do this, you need to lay the electric pump horizontally and unscrew the upper plug, carefully rotate the unit around its axis by 45 degrees. The oil should flow out through the drain hole.

The design of the “Gnome” pump involves two options for immersing it in a working environment:

• mobile, using a flexible polymer cord;
• stationary, using a rigid cable.

Please note that the electric pump must be grounded and the power cord must be reliably protected from mechanical damage.

Three-phase electric pumps may only be connected via a circuit breaker equipped with a thermomagnetic release. This is necessary to protect the motor.

Before starting the three-phase pump, you must make sure that the rotor rotates correctly, changing any two phases: the correct rotation corresponds to a larger head

After checking the pump for oil, mechanical damage and grounding, remove the plug from the pipe. Then attach a flexible hose to the pump and secure it on both sides using clamps.

The diameter of the hose must be selected based on the dimensions of the discharge pipe. In the process, free drainage from the hose must be ensured, its fractures and bends are excluded.

When lowering the “Gnome” electric pump into the pit using a flexible or rigid cable, you need to control that the unit is located strictly in an upright position, as only in this way can the electric motor be cooled to the full. Do not lower the pump using a rope or power cord!

When installing the “Gnome” on a sandy or muddy bottom, or when the condition of the bottom surface cannot be visually determined, care must be taken in advance about the substrate, which, for example, can be a thick rubberized rug.

If there is no substrate, it is recommended to suspend the pump a few centimeters from the bottom. After the pump is immersed in the liquid, it is started. The electric pump should stand upright, the deviation in one direction or another should not exceed 10 degrees.

Safety measures during installation and operation

Operation of the pumps “Gnome” is allowed only within the limits of the pressure characteristic, which depends on the model.Do not bend the hose, rotate and lower the pump to increase the pressure.

The basic electrical safety rules that must be observed during installation, operation and maintenance of the pump:

1. In case of partial or complete interruption of power supply, the pump connection scheme should exclude the possibility of spontaneous start of the electric motor.
2. The “Gnome” pump must be completely submerged in the pumped liquid. Exception: partial immersion is possible for models with a “cooling jacket”.
3. Do not operate the pump with a damaged housing or power cord.

These rules should not be neglected and then the pump will last you as long as possible.

Electric submersible pumps require compliance with safety standards during installation and operation, it is especially important to comply with electrical safety rules

Maintenance of the pumps “Gnome”

Timely and correctly conducted maintenance of the electric pump will significantly extend its service life and protect it from breakdowns, and the owner from expensive repairs. You can carry out maintenance yourself only if it is not possible to do this at a service center.

Maintenance during intensive equipment operation should be carried out once a month. This is a recommendation from all Gnome pump manufacturers.

Monthly maintenance includes:

• oil level and quality control;
• checking for kinks on the hose, insulation breaks on the power cord;
• inspection for mechanical damage to the case;
• measurement of insulation resistance of the cable and motor, which should be more than 0.5 ohms.

Oil is refilled every 250 hours of operation, as well as when water and other foreign liquids and fractions are found in the oil.

To change the oil, it is necessary to install the unit on a flat surface and unscrew the plug in the bearing shield. Drain unsuitable oil and add new ones. For a complete change, about 300 ml of oil is needed.

After using the pump for pumping contaminated liquids with a large amount of mechanical impurities, it is necessary to run the pump for pumping clean water for several hours to clean all internal elements.

If the pump has not been used for a long time, then before starting it is necessary to check whether the impeller rotates: it must rotate without applying force.

For electric pumps “Gnom”, ordinary industrial technical oil of low and medium viscosity or special oil for pumps is used, but its price is quite high

Which “Dwarf" is better to choose?

A large assortment of pumps under the brand name “Gnome” often baffles the average consumer at a standstill, which pump to choose?

To choose the right electric pump, two main factors must be considered:

1. Specifications. The most important parameters are performance and pressure.
2. terms of Use. It is necessary to evaluate the liquid: the temperature background of the medium to be pumped, the percentage and size of mechanical particles, pH indicators and other conditions.

To date, the most popular pumps “Gnome” are models: Mini Gnome 7-7, 10-10, 16-16 and 20-25. The first pump is purchased by gardeners for watering small areas.

The second and third electric pumps have universal characteristics and can be used both for watering the plot and water supply of a small house with 1-3 water consumers, and for draining basements, pits and trenches in private construction.

Gnome pumps with a cooling jacket are used where it is not technically possible to immerse the unit in water

The “Gnome 20-25” pump is a more powerful unit used in private households infrequently, but if you decide to buy this particular pump, then pay attention to the modification in the “cooling jacket”. Most experts recommend buying pumps equipped with a level sensor.

If you plan to use the “Dwarf" to feed clean water from the well, Before buying, be sure to pay attention to its overall dimensions. Remember that the pump is installed strictly vertically, therefore it cannot be used for wells with a small debit.

You may also find our other article useful, which discusses how to get a jammed pump out of the well.

Comparative characteristics of the most popular pumps of the brand “Gnome” used by private consumers, where N is the pressure created by the pump, Q is the equipment performance

Advantages in comparison with analogues

If we compare the “Dwarves” with the analogues presented on the Russian market, then we can distinguish many advantages:

• the presence of a filter that is easily removed and cleaned;
• maintainability, availability of spare parts and their low price;
• wide model range, the ability to choose the best option;
• simplicity in operation and installation; special skills are not required to work with the electric pump;
• the ability to refuse to install shut-off and check valves;
• lack of vibration and noise;
• the presence of a circuit breaker that protects against short circuit and overload, which does not require constant monitoring during operation.

It should be noted that among the pumps that can be used for pumping dirty water, “Gnome” has virtually no analogues.

Information about the best models and manufacturers drainage pumps considered in our other article.

Excellent performance, as well as high quality and reasonable price are the reasons for the high popularity of these pumps in Russia and the CIS.

Conclusions and useful video on the topic

Video about the submersible pump unit “Gnome” of the industrial category:

The device and maintenance of the electric pump “Gnome 20-25”:

Technical characteristics of the modification “Gnome 10-10”:

Submersible centrifugal pump “Gnome” - the best option for pumping dirty water. It has many advantages, and a wide range of models allows you to choose a model for specific needs.

The pump allows for the shortest possible time to pump dirty water in the event of an emergency, and it can also be used as a stationary pump in the water treatment and water supply system.

Do you use the “Dwarf" in your home water supply? Tell us how he copes with his tasks and how often you have encountered breakdowns.

Or maybe you have experience in self-repair of such a pump? Potential buyers may benefit from your experience - leave your comments under this article.