Grundfos circulation pumps: review of popular models, do-it-yourself installation instructions

Main types of breakdowns of Grundfos pumps

If you know how to handle equipment and have an understanding of the technical structure of water pressure equipment, you can repair the pump yourself.

To do this, you will need to correctly determine the cause of the breakdown and choose a method to eliminate it. Pumping equipment almost always breaks down suddenly, without any special warning signs.

All pumps, regardless of their technical characteristics or operating principle, are most often susceptible to the following malfunctions:

• There is no torque on the moving parts of the equipment.
• Spontaneous shutdown of the device.
• High levels of noise or vibration.
• Low water pressure.

If the device hums, but does not spin, then there is a high probability of oxidation of the rotating shaft, or calcification of the rotating parts. This is possible as a result of long-term downtime of internal mechanisms. When the device not only does not spin, but also does not hum, most likely the problem is in the power supply to the motor. Spontaneous shutdown of pumping equipment indicates the presence of mineral deposits between the starter and rotor.

Loud noise during operation is usually caused by air leaks into the water supply pipes due to depressurization of the unit. Vibration indicates faulty bearings on the rotating components of the pump. A drop in pressure is usually caused by clogged filters, or by improper connection of the device to a three-phase power source.

How can you eliminate typical circulation pump malfunctions?

There are a number of typical faults in circulation pumping devices that you can fix yourself. Each block will describe the symptoms of a malfunction, its causes and steps to do it yourself.

The pump is humming, there is no rotation

The cause may be oxidation of the motor shaft during prolonged inactivity of the pump. Troubleshooting instructions.

1. Turn off the power to the equipment.
2. We remove water from the pump and pipelines adjacent to it.
3. Remove the screws securing the housing and the electric motor.
4. We dismantle the electric motor complete with rotor.
5. We turn the rotor by hand or with a screwdriver, resting against the working notch.

The next reason for such a malfunction may be the ingress of foreign objects.

1. Turn off the power to the equipment.
2. We remove water from the pump and pipelines.
3. Remove the screws securing the housing and the electric motor.
4. We remove the foreign object.
5. We protect the pump inlet pipe with a strainer.

The lack of rotation can also be caused by a lack of power supply. To do this, we use a tester to check the presence of power at the terminals in the box and the correct connection of the electrical wires.

The pump does not hum or rotate

The main cause of such a malfunction may be a lack of power supply or insufficient voltage in the network. To eliminate it, you need to use a tester to check the voltage at the terminals and, if necessary, whether the device is connected correctly to the power supply.

Many electric pumps are equipped with a fuse. During power surges, it burns out and requires replacement.

The pump starts working, but stops after a while

The cause of this malfunction may be the deposition of limescale between the stator and the rotating rotor. The malfunction can be eliminated by dismantling the electric motor and cleaning it of limestone deposits.

The pump makes a lot of noise when turned on

The cause of this malfunction may be the presence of air in the heating system pipeline. To eliminate it, you need to bleed the air from the pipes. To automatically release air, it is recommended to install an automatic unit in the upper segment of the pipeline.

If a sharp noise is accompanied by increased vibration, it is recommended to increase the pressure at the inlet to the pumping device. Insufficient pressure can be compensated by increasing the coolant level in the system.

The pump vibrates a lot

The cause of such a malfunction is usually severe wear of the bearing that ensures the rotation of the impeller. The malfunction is eliminated by replacing the worn bearing.

What to do if the pump produces insufficient pressure?

The cause of such a defect may be the wrong direction of rotation of the wheel with blades. The cause of this phenomenon is usually an incorrectly connected phase when connecting three-phase equipment.

Also, a decrease in pressure can be caused by increased viscosity of the coolant, then the impeller encounters too much resistance. To eliminate it, it is necessary to clean the filter on the inlet pipe from deposits, check the cross-section of the incoming pipeline and set the necessary pump adjustment parameters.

What to do if the pump stops after starting?

Most likely, the cause of such a malfunction may be incorrect connection of the wires according to the phases in the terminal box. The fuse on your pump may not be tight enough. Remove it and clean the clamps.

How to disassemble Grundfos

When you are absolutely sure that the cause of the problem is some internal problem in the mechanism, you should begin disassembling the pump.

Before this, it should be disconnected from the power supply and the water should be drained from the internal cavities and tubes. You should start disassembling the device from the junction box, after which a visual inspection of the internal components is carried out. In this way, you can find a burnt or failed part. In a situation where all the components in this part of the device are in working order, you should continue disassembling.

Grundfos deep-well pumps are disassembled as follows:

1. The body is firmly clamped in a vice. This is best done using two halves of a steel pipe of the appropriate diameter. This eliminates the possibility of deformation of the device body.
2. If you cannot unscrew the lid by hand, the threaded seam should be lubricated with a special liquid. Often, silt and dirt accumulate at the junction of the cover and the body itself, making it difficult to turn the thread.
3. After removing the cover, remove the rotor from the working chamber.

When disassembling, the pump motor must be in a vertical position. In this case, the leakage of lubricating oil from it can be avoided.

Which Grundfos pumps are best for underfloor heating?

In order to choose the right Grundfos pump for pumping coolant in heated floors, it is necessary to take into account that the manufacturer has released several models of equipment specifically designed for this purpose

It is worth paying attention to the following modifications:

• Grundfos UPS circulation pumps for water floor heating are popular due to their low cost and good technical characteristics. The disadvantages include a mechanical change in the speed of the pump, lack of adaptation, depending on the actual consumption of thermal energy. For premises with an area of ​​no more than 100 m², the optimal solution would be to purchase a model from the UPS 25-60 series.

Grundfos Alpha2 circulation electric pumps with an electronic control unit for the underfloor heating system, with frequency control of pressure in the water circuit. The regulator automatically adjusts the operation of the pumping equipment, changing the circulation intensity. As a result, power consumption drops almost by half, module efficiency increases and ease of use is ensured.

Depending on the chosen model, the cost of a Grundfos pump varies from 8 to 80 thousand rubles. The price is affected by performance, throughput, and type of control unit. The classification of pumps for underfloor heating includes the UPS series (UPSD, UPE, UPS Series 100 and 200) and Alfa, Alfa2, Magna.

How to properly connect a Grundfos pump to a heated floor system

The Grundfos module is mounted in a manifold for underfloor heating using special pipes. For convenience, the connectors are engraved with arrows indicating the installation direction. The first start of the module is performed only after the system is filled with coolant. Connection to the electrical network is made through the terminal box. The housing is installed strictly in a vertical position.

Grundfos pumping equipment is the optimal solution for multi-circuit heating systems. Technical parameters allow connection to solid fuel, liquid fuel and gas equipment.

Grundfos repair

To diagnose the engine, you will need an ohmmeter.

When you rotate the handle of this device, it produces a voltage of about 200V. If the ohmmeter readings are extremely high, tending to plus infinity, then there is a break in the working phase. If the resistance values ​​are very small, then we can confidently talk about a short circuit between the turns of the electric motor. It is impossible to carry out high-quality engine repairs with such problems at home, and it should be taken to a specialized workshop.

If everything is in order with the engine and electrical equipment, the cause of the malfunction may be mechanical breakdowns, or clogging of the internal working spaces with debris, silt, or mineral deposits. In this situation, the insides of the pump are washed in running water and thoroughly cleaned with a brush. Particular attention should be paid to bearings, water supply wheel, and valves. O-rings and seals must be in good condition, elastic and without mechanical damage.

After cleaning the parts and components, you can reassemble the device and try to start it up again. At the same time, do not forget to fill the working chambers of the device with water. Running it “dry” will certainly lead to an even more serious breakdown, after which it will be necessary to repair the pumping station at a service center.

Features and benefits of pumps

The main advantages of Grundfos pumps are:

• The optimum ratio of price and quality,
• high energy efficiency of equipment,
• a huge selection that can satisfy any need.
• quite long service life,
• good technical support.

When choosing pumping equipment, the following technical parameters must be taken into account:

First you need to decide what type is needed. In total, there are three large groups: for wells, for heating, for drainage or sewerage. At Grundfos, designers have thought through in advance almost all possible problems that may arise in a particular area of ​​operation. Therefore, when choosing equipment from this manufacturer, you get a unit that takes into account many years of experience.

Before ordering equipment, you need to decide what type of voltage will be used: single-phase or three-phase. For household pumps, single-phase pumps are mainly used; in industry, three-phase pumps are more commonly used.

The main characteristic when choosing a pump is the graph of pressure versus flow. This graph shows how much water the pump will pump depending on the required pressure. The higher the pressure that needs to be maintained, the less water the pump can pump. When choosing equipment, the required operating point must be under its curve. It is also necessary to provide a margin of 20% for the supply.

Power is also an important parameter. It depends on the current and voltage. This parameter is taken into account when selecting pump protection, as well as when calculating the required cross-section of power supply cables. The higher the power, the greater the productivity.

When choosing pumps, it is also necessary to take into account geometric parameters and connection dimensions

Before placing an order, you must make sure that the selected equipment is suitable both in weight and dimensions.

Depending on the operating conditions, it is necessary to pay attention to the minimum and maximum permissible temperature of the pumped medium. There are cases when the wrong choice of range led to equipment failure

Also, when choosing from equivalent pumps, you need to choose the one with a higher efficiency rating

In the long term, such equipment will provide significant energy savings.

In order for the unit to work for a long time and without interruptions, it must be installed correctly. Installation of any equipment must be carried out strictly according to the attached installation instructions. Also, do not forget about installing automated control systems for pumps.

Such a system will protect your unit from power surges, from engine overheating, from the possibility of working without water, from water getting inside, etc., and will also allow you to control the process automatically, without human intervention.

Another condition for durability is proper operation. It is also written in the instructions

It is important to understand that if a pump unit protection system is installed, then you need to be alert when it is triggered. It is best to carry out a full cycle of equipment inspection. https://www.youtube.com/embed/0_9CFtB_0RE

Grundfos service

To avoid the above problems, you should follow the operating rules of pumping equipment, as well as perform timely maintenance. Installation of Grundfos deep-well equipment and trial operation are best left to professionals. Before starting pumping stations, you should always make sure that there is water in them to avoid dry starting.

If you use the pump only in the summer season, then the rest of the time it should still be turned on, at least for half an hour every 3-4 weeks. This will avoid problems with oxidation of its internal parts. With Grundfos drainage pumps, special attention should be paid to the permeability of pipes and pipes. Since such equipment operates in particularly difficult conditions, which entail the risk of clogging, it is necessary to clean it from time to time with a strong stream of water.

Grundfos equipment, due to its reliability, performance and ease of operation, is widely used in all industries.

They are used in the housing and public utilities sector in the construction of centralized heating, water supply, sewage drainage, servicing agricultural and forestry enterprises, as well as in equipping industrial complexes.

Pump energy efficiency

Well-known European manufacturers of pumping equipment have made great strides in optimizing energy consumption, introducing several wet rotor models to the market. This was achieved through the use of modern DC electric motors controlled by a controller. Such models belong to class “A” equipment, which is considered the most effective in terms of minimizing energy losses - their consumption does not exceed 0.09-1.3 kW).

Grundfos specialists have developed a whole series of energy-saving pumps under the names ALPHA2 and MAGNA3. The former are distinguished by simple functionality and are intended for use in heating and hot water systems of private houses. Models of the second type have the AUTOAdapt function, which allows you to automatically set the optimal power consumption mode. Their capabilities meet modern requirements for the efficiency and performance of equipment in this class. They are designed for use in heating systems of private homes and industrial enterprises.

Stages and rules of repair

Repair of the Sololift pump, as well as repair of a Grundfos pumping station for any purpose, can be done independently, having first identified the source of the problem.

Equipment diagnostics involves several stages:

• start the pumping station, assess the noise and vibration levels;
• check the pressure indicators;
• make sure that the motor does not overheat during operation;
• check the presence and quality of lubrication of node connections;
• make sure the integrity of the structure and the absence of leaks;
• inspect the box for secure fixation of the terminals.

How to carry out regular pump maintenance?

From time to time, preferably at least once a month, it is necessary to carry out an external inspection and check the quality operation of your circulation pump device.

Pump design option

1. Turn on the pump and in operating mode, check for any extraneous noise or excessive vibration.
2. Check the coolant pressure supplied by the pump. It must correspond to the indicators stated in the technical data sheet.
3. Make sure that the electric motor of the device does not become overheated.
4. Check the presence of grease on the threaded flanges and, if necessary, restore it.
5. Make sure there is a ground connection between the pump housing and the appropriate terminal.
6. Inspect the pump from all sides and make sure there are no leaks. Typically, such vulnerable points are the interface between the pipeline and the housing of the pumping device. Check the tightening level of the bolts and the normal condition of the gaskets.
7. Inspect the terminal box. All wires must be securely fixed. The presence of moisture in the unit is unacceptable.

Key characteristics of Grundfos circulation models

Let's look at the Grundfos circulation pump models on the market today.

Magna

The devices presented in this series are designed to ensure the circulation of coolant in heating systems with variable flow. You can place the device anywhere, which will allow you to optimize energy costs.

The main task performed by the pump of this series is the regulation of water circulation parameters. It is for this function that the design of the unit with its controls is intended. It is also necessary to take into account how well the pump parameters correspond to the communication requirements.

Due to the pressure of 16 bar, Grundfos Magna pumps can be used in large houses with a long circuit length. Users note and note the benefits of the Magna line pump indication system, which in some versions is represented by several light warning fields.

Twin circulation pumps GRUNDFOS MAGNA3 D 32-80

UPS

This series is represented by three-speed models, which are available in two main modifications - 50 and 60 Hz. The UPS 100 line includes over 25 models of circulation pumps, the price of which starts from 6,000 rubles and ends at 40,000 rubles.

The Grundfos UPS 100 series features glandless rotor circulation pumps. In the design of such units, the working elements and the engine are located in one housing, while the rotation shaft and the impeller fixed on it are isolated from the pumped working medium.

Thanks to this design, it is possible to use only two sealing glands, without a mechanical seal, due to which the unit design is simpler and at the same time reliable. All pump models are equipped with ceramic bearings, which have a long service life.

During the operation of the pump, they are lubricated by the pumped liquid. In addition to heating systems, such devices can be installed in the following areas:

• industrial heating and water pumping systems;
• heat pump systems;
• underfloor heating systems;
• geothermal heating;
• heat recovery systems;
• air conditioning;
• refrigeration units.

In addition to the operational advantages of these devices, it is worth noting their high performance, efficiency reaches 80%. The units are distinguished by their reliability, maintainability of design, and long service life. Another important advantage is the ability to operate in three speed modes, due to which you can configure the pump to any operating mode.

Grundfos UPS circulation pump design

The advantages of the Grundfos UPS 100 series pumps include:

• simple electrical connection;
• no need for additional electrical protection. This is due to the fact that current-resistant interlocking motor windings are used here;
• hollow shaft design, through a hole in it air escapes from the chamber;
• no maintenance required.

The downside is the fairly high noise level during operation of the device (only models with a dry rotor do not produce any distracting sounds) and the high cost. However, due to the high reliability that characterizes the design, its price is absolutely justified.

As already noted, the Grundfos company presents more than 25 models of circulation pumps in the UPS 100 line. Let's look at the most popular modifications:

• Grundfos UPS 25-40 (7,000 rubles);
• Grundfos UPS 32-100 (35,000 rubles);
• Grundfos UPS 40-50F (27,000 rubles);
• Grundfos UPS 20-60 130 (10,000 rubles).

How to calculate the power of a circulation pump for heating and hot water supply?

The Grundfos UPS 25-40 circulation pump is considered the most affordable. This is a small unit, which is characterized by economical energy consumption and makes virtually no noise during operation. Such a pump is a device with a dry rotor, in which the rotor and the motor are not in contact with the working fluid.

The unit has three fixed circulation speeds, which can be switched using a lever located on the terminal box. Thanks to the built-in automation, you can set any operating mode - continuous, by timer, or based on the characteristics of the coolant.

The main technical characteristics of Grundfos UPS 25-40 are as follows:

• power is 25/38/45 W;
• operating pressure reaches up to 10 Bar;
• temperature of the pumped liquid -25+100°C;
• operating flow is 1.6 m³/hour;
• pressure reaches up to 4 m;
• threaded connection standard - G 1 ½.

The circulation pump UPS 25-60 and UPS 20-60 are considered more functional models. Such units, in addition to heating systems, can be used in hot water supply, cooling and air conditioning systems. The models are intended for pipelines with a stable flow rate of the working medium, the pressure of which is no more than 10 Bar, and the hydrostatic head is 1.62 m. In the UPS 20-60 pump, the nominal flow rate is increased to 2.3 m³/hour.

The body of the described models is made of cast iron, the impeller is made of a corrosion-resistant composite alloy. The installation length of the pump is 130 mm.

You can buy a UPS 25-60 circulation pump with nuts for 7,000 rubles. The unit has a simple and reliable design, its quality meets high German standards. The device can operate at three speeds, at which a shaft made of ceramic, as well as bearings, can rotate. The power of the described circulation pump is 60 W, productivity is 71 l/min.

The Grundfos UPS 25-80 model is classified as expensive, its price is 13,000 rubles. Such equipment is used to circulate hot and cold water. The case is small, so you can mount it anywhere.

The structure is made of cast iron, the impeller is made of heat-resistant composite material, which contributes to the high anti-corrosion properties of the unit. Such devices can be used for single-pipe and two-pipe heating systems. The circulation pump Grundfos UPS 25-80 has a power of 165 W. The productivity of the unit is 125.25 l/min. The lifting height is 8 m. The maximum liquid temperature is 110°C. The pressure is 10 atm.

Recommendations for choosing UPS series circulation pumps

The most important factor on the basis of which a circulation pump is selected is the flow rate of the heating system. It is based on the flow rate that the required pump capacity is determined - the volume of water that it must drive through the circuit for one hour.

In the table we present the main parameters of circulation pumps series 100 (with nuts) UPS.

Alpha

Distinctive features of the Grundfos Alpha circulation pump are its ability to work with climate control equipment. The power of the units is based on classic circulation pumps. The most popular models: Grundfos Alpha2 L 25 60, Grundfos Alpha2 L 25 40.

In the basic configuration, Grundfos Alpha provides a throughput of 3 m³/hour, and the equipment pressure reaches 6 m. The advantage of the models is the temperature of the pumped liquid, which can vary from 2 to 110°C.

The most modern modifications are characterized by the unique ability to automatically perform settings. All you have to do is place the pump in the communication circuit, and it will then calculate the appropriate operating parameters.