Circulation pump for hot water supply: description and characteristics

The circulating pump for DHW acts as one of the important components of the system. Without this equipment, it will not be possible to achieve pressure, as well as water circulation in the wiring. Therefore, before purchasing this unit, it is necessary to take into account the nuances that affect the efficiency of work and purpose.

Description in terms of design features

Comparing several models of circulation pumps, you can understand that, first of all, they differ from each other by the type of rotor. On this basis, the described equipment can be classified into devices with:

• Wet rotor;
• Dry rotor.

In the first variant, the support part, which assumes the presence of the impeller, is placed in the pumped medium. In this case, the hot heat carrier acts as lubricant and coolant. Pumps with a wet rotor almost do not make noise at work and are characterized by a long service life. They are cheap and do not require maintenance. This indicates that such a circulating pump for DHW can be supplied and forgotten about it.

However, similar aggregates have disadvantages, one of which is expressed in a low coefficient of efficiency, it ranges from 40 to 45%. Among other things, positioning the pump is limited, because you can only install it horizontally. Therefore, this equipment is purchased by those people who want to equip the heating and water supply system in a small house. After all, this unit is not capable of great achievements.

Description of the pump with a dry rotor

A circulating pump for DHW can also have a dry rotor, in which the power plant is separated from the pumped medium. The rotor remains dry during operation, which leads to problems with cooling and lubrication. The problem is solved by periodic inspection, as well as with the help of a fan.

Dry pumps cost more in the long run, both at the acquisition stage and at the service stage. But these efforts will be rewarded with more impressive productivity, which reaches 70%. Therefore, a similar circulating pump for DHW can be purchased for installation in municipal and industrial systems.

Main operational characteristics

As the main task of the described equipment is maintaining the speed of the water flow through the wiring. Therefore, the main criteria that affect the choice of the pump are:

• The value of pressure;
• consumption;
• Heat transfer.

The pressure head is determined by the height of the water column, which will determine the pressure and temperature at the return. With regard to flow, it is determined by the formula as a quotient of the power and temperature difference in the treatment and the pressure pipe. Heat output is determined by the area of the heated room and the heat losses.

Wilo-Star-Z pump description

When choosing a DHW circulation pump, you can pay attention to the model mentioned above. It is a unit with a wet rotor, which can be used to maintain pressure in water and heating networks. This model has a mechanical shut-off valve and electronic stuffing.

As for the first component, it assumes the availability of a ball valve at the outlet and a non-return valve. The electronic component is:

• display;
• thermostat;
• timer.

This version of the pump can be used in conventional systems and high-tech networks that are built into the smart home system. The Wilo DHW circulation pump has a thermal disinfection detection system, which is used when working with drinking water.

Characteristics of VortexBW 152

This equipment is manufactured in Germany, which means it has high quality. The model is characterized by high performance and maintainability. To disassemble the device can be quite simple, and the unit itself is not necessary to dismantle. Without removing from the pipe, the pump can be cleaned of scale. It works absolutely silently and differs from analogues in modest sizes, therefore it is quite often used in everyday life.

Description of ESPA RA1-S pump

This circulating pump for DHW systems is another representative of equipment with a wet type rotor. It can be used for air conditioning and ventilation systems. In the role of the main difference from analogues is the possibility of vertical installation. The equipment can be used in cold water and hot water supply systems. The device is capable of pumping hot flammable liquid, the temperature of which reaches 120 ° C. In everyday life the device has proved itself positively, it is efficient and economical.

Grundfos UP Technical Data

The circulation pump DHW UP is a device with a heat-insulating casing, the flow part of which is insulated from the stator by a sheath. The engine has a wet rotor, which provides almost noiseless operation. If necessary, the equipment can be disassembled without removing the hull from the pipeline. Maintenance does not require the unit.

This circulating pump for Grundfos hot water can operate in one of three speeds, its electric power is 25 W, working pressure is 10 bars. The temperature of the pumped medium can vary between 2 and 95 ° C. The recommended set is 0.93 m, while the connection is made with the following parameters Rp 1/2. The recommended feed rate is equivalent to 0.38 m ³ / h. The installation length is 80 m, the maximum head is 1.4 bars. The device weighs 2.6 kg, and the water protection class corresponds to the designation IP42.

The main features and advantages of Grundfos UP pumps

Before you buy the Grundfos UP pumps , you should consider their distinctive features from the analogues, they consist in:

• A spherical rotor;
• Low noise level;
• Protection from calcareous deposits;
• Long service life.

The consumers choose these devices also for the reason that their operation is accompanied by insignificant consumption of electricity. In the manufacturing process, high-quality materials are used, and any household master can install the device.

After installing such a pump, you can get hot water as soon as you open the tap. The presence of a spherical rotor almost eliminates the blockage of the impeller by calcareous deposits and impurities. The plug-in connector is reliable and simple, thanks to this connection to the mains is much simplified, as well as operation.

Pumped media and operating limitations for Grundfos circulation pumps

Before purchasing a circulation pump, it is important to consider pumped media. In the case of Grundfos UP models, they are able to work with aggressive, non-viscous, clean fluids that do not have solid particles and fibers. Work such equipment is capable of water, which was previously softened. There are certain operational limitations that are expressed in the maximum possible kinematic viscosity of water, it is 1 mm ² / s, which is true for a temperature of 20 ° C.

Conclusion

Before choosing a circulating pump, it is necessary to take into account the expected pressure of water flowing out of the tap. The maximum allowable value of this parameter is 4.5 bars, while the minimum is not regulated.

It is necessary to take into account the number of faucets that can be opened simultaneously. If you create a pressure of 5 bar in the pipeline, then when you open one tap, the head will be above the permissible value, and the jet will damage the plumbing equipment.