Circular pumps manufactured by the Danish company "Grundfos" belong to the classic equipment, the design of which has undergone significant adjustments over the past 100 years. The technical characteristics of many models have changed, as well as the scope of their application has expanded. The Grundfos circulation pump for heating is the main and constant component of modern heating systems for industrial and residential buildings.
Circulation pump device Grundfos
According to their design, circulation pumps for heating Grundfos are divided into two types: with a "wet" and with a "dry" rotor. The first of the constructions historically appeared before the second version. It is based on a body made of cast iron, steel, bronze or aluminum, inside which a movable rotor is located in an aqueous medium. An impeller is installed on the shaft, which sets the working fluid in motion.
Pumps with a "dry" rotor began to be produced a little later, the engine and the liquid in them are separated from each other. First class pumps are highly reliable thanks to liquid lubrication. But at the same time, the efficiency of such devices is very small (no more than 50 percent).
For units with a "dry" rotor, the efficiency is slightly higher (it reaches 70%). These models are most often used for industrial purposes, where operating conditions involve pumping large volumes of water. For domestic needs, circulating pumps operating on a "wet" circuit are usually used.
Specifications
The main technical indicators to which attention is paid when choosing a suitable equipment model are:
- graph of the dependence of the fluid pressure on the amount of its supply to the system
- power consumed by the engine of the unit from the network;
- coolant performance;
- permissible temperature of the pumped medium;
- dimensions and weight of the device.
The first of the characteristics makes it possible to understand what volumes of water are pumped by the pump, depending on the pressure developed in the system. The higher this indicator, the less water resource must be passed through the unit to obtain the required pressure. To correctly select a sample of equipment, the operating point must be located under the curve of the graph. When choosing this indicator, it is desirable to provide a supply margin of at least 20%. Another parameter is directly related to it - pump performance.
The power taken from the network is determined by the amount of current in the load and the supply voltage (220 or 380 volts). This parameter is taken into account when selecting protection devices for current supply circuits and when calculating the cross-section of wires that are part of the supply lines of power supply. The specified value depends on the performance of the pumping equipment, which increases with its increase.
The dimensions of the purchased sample and its weight are also taken into account when choosing a suitable model. This also applies to the operating conditions of the pump - the minimum and maximum permissible temperature of the pumped medium. The reliability and durability of the purchased sample depends on the correct selection of this indicator.
Advantages and disadvantages
The advantages of pumps from a Danish manufacturer include:
- high work efficiency;
- reliability of all units and parts;
- low level of intrinsic noise;
- versatility of application.
Grundfos pumps are used as part of heating systems and are in demand for organizing hot water supply (DHW) circuits. In addition, they can be installed in floor heating systems or in climatic equipment.
The versatility of Grundfos units is also manifested in the fact that after purchasing them, the user will be able to work with the following types of coolants:
- water heated to a certain temperature;
- antifreeze that does not contain solid components;
- heat carrier with the addition of ethylene glycol in a volume of not more than 40 percent.
The advantages of equipment samples of this class include the operation of the rotor in direct contact with the coolant; it is separated from the rest of the units by a metal glass made of stainless steel. In addition, in these models, the inlet and outlet pipes are located at the same level, which determines the quiet operation of the entire unit. The significant advantages of products from a Danish manufacturer include:
- optimal ratio of the declared price and quality;
- high rates of energy efficiency;
- a large selection of models that can satisfy the most demanding customer;
- long service life and advanced technical support system.
The characteristic disadvantages of Grundfos pumps are considered to be a relatively high price per unit of goods (from 6500 rubles) and the absence of a cable for connecting to the mains in the kit.
Features of choice
When choosing the right sample of pumping equipment from Grundfos, much attention is paid to the diameter of the union nuts. It is selected depending on the size of the pipe being prepared for installation in the heating system:
- if a polypropylene pipe with a standard size of 20, 25 mm is used - nuts with a diameter of 25 mm are suitable for installation;
- when using pipes with a larger diameter (or steel billets from 25 mm and above), it makes sense to purchase equipment designed to use union nuts with an inner diameter of 32 mm.
If the listed requirements are met, the installation of the equipment will not cause serious problems if you follow the instructions in the instructions.
Pump energy efficiency
Renowned European pumping equipment manufacturers have made great strides in optimizing energy consumption by introducing several wet rotor models to the market. This was achieved through the use of modern DC motors, controlled by a controller. Such models belong to the equipment of class "A", which is considered the most efficient 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 called ALPHA2 and MAGNA3. The first ones are distinguished by simple functionality and are intended for use in heating and hot water supply systems in private houses. Models of the second type have the AUTOAdapt function, which allows you to automatically set the optimal power consumption mode. Their capabilities correspond to modern requirements for indicators of efficiency and productivity of equipment of this class. They are designed for use in heating systems of private houses and industrial enterprises.
Modes of operation
The modern recirculation pump for heating belongs to multifunctional devices. Various samples of this equipment are capable of operating in the modes indicated in the passport, including "fixed speed". All of them are equipped with a synchronous motor, the operation of which is controlled by an integrated processor. During operation of the unit, the control unit registers the following basic parameters:
- current strength;
- rotor speed;
- temperature in the working area and others.
Its presence allows you to adapt to a specific heating network with an optimal energy consumption mode.
Parsing the pump with your own hands
Any user who has studied the design well can disassemble the purchased sample of pumping equipment, if desired. The need for this often arises when it is necessary to repair it or overhaul with the replacement of worn parts. After complete disassembly, the main working units of the mechanism are inspected, and then checked for wear.
The main attention is paid to the examination of the state of the "wet" rotor. It should be removed and replaced with a new part in the presence of a repair specialist who can control this difficult operation.
Popular models rating
The pump rating is based on a comparison of the technical characteristics and operational capabilities of the three models. The product is in the first place Grundfos UPS 25-60 (N) 180, which is a circulation unit with a cast iron body (this option is used only for heating). Its modification for hot water supply has a stainless steel body. All samples are equipped with a single-phase asynchronous motor, a speed switch and a special sleeve that separates the rotor and stator.
The advantages include:
- admissibility of use in any kind of contours (in closed and non-closed);
- durability and efficiency (consumption no more than 60 W);
- low noise level (up to 43 dB);
- compactness, low weight and overheating protection;
- ease of installation and maintenance;
- long service life.
The disadvantages of these products are considered obsolescence of certain models and their high cost.
The second position is taken by the brand pump Grundfos ALPHA2 25-40 180equipped with a built-in permanent magnet motor. The power consumed by this device from the network is 0.022 kW, and the capacity is 2.4 m3 / hour. At an operating temperature of the coolant from +2 to +110 ° C, the pressure created in the circuits is 4.0 meters.
This product has a pure cast iron housing and is equipped with an efficient wet rotor motor and ALPHA plug. The unit can be installed vertically or horizontally, which after start-up is controlled by means of built-in electronics. All information about the possible modes of operation of the device, its power consumption and typical breakdowns is displayed on the display located on the front panel.
The positive aspects of this model include:
- Low power consumption (only 22 watts).
- Small size (10 × 15 × 18 cm) and light weight (2.1 kg).
- Low noise figure during operation (no more than 43 dB).
- Protection against corrosion (the body is made of stainless steel).
- The presence of the AUTOADAPT function, as well as the ability to select night or summer mode.
- Low level of heat losses (the body is insulated with a protective casing).
- Possibility of setting fixed operating modes.
- Long-term guarantee (up to 5 years).
The disadvantages of this product are considered to be frequent failures in the operation of the electronics, as well as the lack of special protection against dry running.
The third place is confidently taken by the product Grundfos UPA 15-90 (N) - a modern monoblock unit with characteristics slightly worse than the previous model.
