The DHW circulation pump 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 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 in 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 supporting part, which assumes the presence of an impeller, is placed in the pumped medium. In this case, the hot coolant acts as a lubricant and coolant. Glandless pumps are almost silent during operation and are characterized by a long service life. They are cheap and require no maintenance. This indicates that such a circulation pump for hot water can beput and forget about it.
However, such units also have disadvantages, one of which is expressed in low efficiency, it ranges from 40 to 45%. Among other things, the positioning of the pump is limited, because it can only be installed horizontally. Therefore, this equipment is purchased by those people who want to equip a heating and water supply system in a small house. After all, this unit is not capable of great accomplishments.
Glanded pump description
The DHW circulation pump 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 are more expensive in the long run, both at the acquisition stage and at the maintenance stage. But these efforts will be rewarded with more impressive performance, which reaches 70%. Therefore, a similar circulation pump for domestic hot water can be purchased for installation in utility and industrial systems.
Main performance features
The main task of the described equipment is to maintain the speed of the flow of water through the wiring. Therefore, the main criteria that affect the choice of pump are:
- pressure value;
- expense;
- heat dissipation.
The pressure parameters are determinedthe height of the water column, the pressure and temperature on the return will depend on this. As for the flow, it is determined by the formula as the quotient of the power and the temperature difference in the processing and pressure pipe. Heat transfer is determined by the area of the heated room and heat loss.
Description of the Wilo-Star-Z pump
When choosing a DHW circulation pump, you can pay attention to the model mentioned above. It is a wet rotor unit that can be used to maintain pressure in water and heat networks. This model has a mechanical shut-off valve and an electronic filling.
As for the first component, it assumes the presence of a ball valve at the outlet and a check valve. The electronic component is:
- display;
- thermostat;
- timer.
This pump option 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 for drinking water.
Characteristics VortexBW 152
This equipment is made in Germany, which means it is of high quality. The model is characterized by high performance and maintainability. You can disassemble the device quite simply, and the unit itself does not need to be dismantled. Without removing from the pipe, the pump canbe descaled. It works completely silently and differs from analogues in its modest size, so it is often used in everyday life.
ESPA RA1-S pump description
This DHW circulation pump is another wet rotor equipment. It can be used for air conditioning and ventilation systems. The main difference from analogues is the possibility of vertical installation. It is possible to use the equipment in systems of supply of cold water and hot water supply. The device is capable of pumping heated flammable liquid, the temperature of which reaches 120°C. In everyday life, the device has proven itself positively, it is productive and economical.
Specification Grundfos UP
The DHW circulation pump UP is equipment with a heat-insulating casing, the flow part of which is isolated from the stator by a shell. The engine has a wet rotor, which ensures almost silent operation. If necessary, the equipment can be disassembled without removing the housing from the pipeline. The unit is maintenance free.
This Grundfos DHW circulating pump can be operated at one of three speeds, its electric power is 25W, and the operating pressure is 10bar. The temperature of the pumped medium can vary from 2 to 95°C. The recommended set is 0.93 m, while the connection is made with the following parameters Rp 1/2. Recommended servingequivalent to 0.38m3/h. The installation length is 80 m, the maximum head is 1.4 bar. The device weighs 2.6 kg, and the water protection class corresponds to the designation IP42.
Key features and benefits of Grundfos UP pumps
Before you buy Grundfos UP pumps, you should consider their distinctive features from their counterparts, they are:
- spherical rotor;
- low noise;
- protect against lime deposits;
- long service life.
Consumers choose these devices also for the reason that their operation is accompanied by low power consumption. High-quality materials are used in the manufacturing process, and any home 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 blocking of the impeller by lime deposits and impurities. The plug connector is reliable and simple, thanks to which the connection to the mains is greatly simplified, as is the operation.
Pumped media and operating limits for Grundfos circulation pumps
Before purchasing a circulation pump, it is important to consider the media being pumped. When it comes to Grundfos UP models, they are able to work with aggressive, non-viscous, clean liquids that do not contain solid particles and fibers. Such equipment is capable of working with water that has previously been softened. Existcertain operating limits, which are expressed in the maximum possible kinematic viscosity of water, it is 1 mm2/s, which is true for a temperature of 20°C.
Conclusion
Before choosing a circulation pump, it is necessary to take into account the expected pressure of water flowing from the tap. The maximum allowable value of this parameter is 4.5 bars, while the minimum is not regulated.
You also need to take into account the number of water taps that can be open at the same time. If you create a pressure of 5 bar in the pipeline, then when one tap is opened, the pressure will be higher than the permissible value, and the jet will damage the plumbing equipment.
