We are all accustomed to the fact that in a hot water supply system water moves solely due to main pressure. On the one hand, this is not bad, but such a water supply system has one significant drawback - when we open the tap, we wait for the cold liquid to drain, and only after that we enjoy the benefit of civilization called “hot water.” Agree, a little wrong. It is this problem that the circulation pump for hot water is designed to solve, which we will talk about in detail in this article - together with the website, we will talk about how the correct hot water supply system works in a private house.
Circulation pump for hot water photo
Circulation pump for hot water supply: what is it used for and how does it work
You already understand that having installed a hot water pump, you will not wait until cold liquid flows from the tap. The only thing that is not entirely clear is the operating principle of this pump. It is simple and consists of constructing a closed circuit through which hot water constantly circulates. That is, a ring along which water moves endlessly and is periodically heated to a given temperature. A faucet can be installed or a mixer connected anywhere in this ring.
Anticipating your next question, I will say that hot water does not enter this circuit through a heating device that uses fuel to heat the water. This circuit is powered from the heating boiler through a special heat exchanger called - the water here is heated by. In fact, a battery (coil) is mounted inside such a boiler, upon contact with which the water heats up. This is not a instantaneous water heater - it is a storage boiler that has at least five connection pipes. Two of them are used for connecting to heating, two for circulating hot water (supply and return, so to speak) and one for supplying cold water to the tank.
Recirculation pump for hot water photo
If we describe the operating cycle of such a unit, it looks like this. When the tap on the mixer is closed, the water moves in a circle thanks to the circulation pump and is heated by the coil to the maximum temperature limit. As soon as you open the mixer, water flows out - at the same time, fresh cold water enters the indirect heating tank from the water supply, which is immediately heated from the coil. In general, the same thing happens here as in a regular electric one, only instead of a heating element it uses a coil.
When and how it is advisable to use a hot water circulation pump
Such a scheme for hot water supply in a house is not always advisable - in short, in small houses with 3-5 rooms it is unjustified. For such cases, a regular double-circuit is suitable - the short length of the hot water supply lines will not make you wait long for heated water to flow from the tap. Another thing is large houses with several bathrooms and a complex heating system. This is where it shows itself one hundred percent with a circulation pump. What problems are solved in this way?
- First of all, there is always hot water in the tap - there is not a second of waiting until you get heated water.
- The second point is the increase in pressure in the system. In large houses, as a rule, pipes stretch over a long distance - the result of the long length of pipes is a weakening of the pressure in the system, which is compensated by the recirculation pump for hot water.
These are the main tasks of the hot water supply ring circuit. As a bonus, it provides a couple more benefits.
Among other things, the pump itself allows you to save resources. He can do this solely due to the ability to program the on time. Let's just say that hot water is not used at night, which means there is no need to operate the circulation pump for hot water. Therefore, you need to program it so that it turns on half an hour before you go to the bathroom. What are the savings here? When circulation stops, the water in the circuit quickly heats up and the heat exchanger stops taking heat from the heating circuit. In turn, the coolant in it cools less, as a result of which less fuel will be needed to heat it to a given temperature.
How to choose a pump for hot water supply
First you need to understand the difference between a heating circulation pump and a domestic hot water pump. It consists of three points. First of all, this is the ability to withstand a certain coolant temperature. If heating circulation pumps are capable of working with coolant heated to almost 100 degrees, then DHW pumps can only withstand heating up to 65 degrees. Secondly, heating pumps are made of cast iron, and domestic hot water pumps are made of brass. And thirdly, pumps for hot water supply at home have less power reserve.
At first glance, it may seem that a regular hot water supply system can be installed - unfortunately, this is not the case. These two types of pumps are not interchangeable, which must be taken into account first of all when approaching the issue of choosing a circulation pump for a hot water supply system.
In addition, when choosing this equipment, it is necessary to take into account the following points.
Also, when approaching the issue of choosing a circulation pump for hot water, it is worth mentioning double pumps for hot water - they simultaneously supply coolant to the indirect heating boiler, and push the hot water heated by it through pipelines. It’s a good thing, but expensive—separately, these two pumps would cost less.
And finally, I’ll say a few words about modern pump manufacturers who have already proven themselves exclusively on the positive side. Grundfos is considered the undoubted leader in this industry today - it supplies the market with economical pumps equipped with several protections. Pumps of this trademark protected from dry running and, as a rule, have built-in pressure sensors. The second manufacturer of pumping equipment that is worth paying attention to is Wilo. German by origin, who offers circulation pumps for hot water supply, as they say, for every taste and color - in the range of these products you can find pumps with a mechanical timer and with electronic control. As they say, for all occasions and for any budget. And an economical option called DAB - despite the low cost, the company produces very high-quality equipment with a long warranty period.
- a device designed for pumping liquid through the hot water supply system of a house. Using this equipment you can heat the room, supply all the taps hot water. Using a circulation pump allows you to save on electricity and avoid waste of water. The main thing is to take a responsible approach to choosing a model, choosing a unit that can fully satisfy your needs.
Using a circulation pump for a hot water supply (DHW) system or heating in a private house
The essence of the circulation pump is the constant distillation of water through the system, which does not allow it to cool. Installing such a device will significantly improve the living conditions in a private home if there is a need for constant availability of hot water, heating the water in the pool or heating.
In homes where water heaters are installed to produce hot water, a considerable amount of liquid has to be drained until hot water flows, and this significantly increases its consumption. The optimal way out is to select a circulation pump that minimizes the differences between centralized and autonomous water supply.
Thus, we can distinguish three main tasks that can be solved by installing this equipment:
- Hot water supply;
- Air conditioning;
- Heating.
The principle of operation of the circulation pump: a closed main pipeline running throughout the building, with pipes extending from it to all water supply points, is connected to the boiler.
Hot water continuously circulates through the system, which allows households to get water at the desired temperature at any time by simply opening the tap. They don't have to drain cold water, waiting until the liquid warms up. Connects to tank return pipeline, so that unused liquid flows back.
Circulation pump with high performance, it is small in size, affordable in price, consumes little energy, is quiet and easy to install, which makes it more attractive to consumers.
What parameters should you focus on when choosing a pump for hot water in your home?
The pump should be selected according to its characteristics, which is the dependence of two indicators on each other:
Pressure
The flow force must be sufficient to ensure good pressure at all water supply points, taking into account possible hydraulic losses. Highest value The hydraulic resistance of the system that the pump is able to overcome is called maximum pressure. Pressure is measured in meters of water column.
Performance
Before choosing, it is necessary to calculate the maximum load of the system and compare it with the performance of the pump. Typically in a house the value of hydraulic resistance is is within 0.1 – 0.2 atm. The largest value of the pumped amount of coolant per unit of time is maximum productivity.
Not superfluous features include protection against lime deposits, low noise levels during operation, and low power consumption.
Also, when choosing the optimal model, it is worth taking into account the operating conditions: type of boiler for DHW, required liquid temperature, pipeline diameter, etc.
Optimal choice - how to choose the right model
Design of a water circulation device
There are two varieties of this device for water circulation: with dry and wet rotor.
Units of the first type are characterized by large dimensions and noise, and lack of natural lubrication, since the rotor remains dry (the device is separated from the pumped liquid). But pumps with a dry rotor are characterized by high performance (up to 70%), because the engine is less susceptible to heating from the coolant.
Glandless rotor pumps, on the contrary, are small in size and make virtually no noise during operation. The impeller and rotor are installed directly in the pumped liquid, which provides both lubrication and cooling, and helps absorb noise from operation.
Due to the accumulation of deposits on the surface of the device, the rotor may jam; the equipment must be inspected regularly.
The temperature range at which the unit is able to function normally is much wider for pumps with a dry rotor than for pumps with a wet rotor. In this regard, these “dry” ones are more often used in industry, and “wet” ones in private homes, especially since the latter are cheaper.
In addition, there is a division according to the type of connection: with flange and coupling connections.
Models in which the suction and pressure pipes are located on the same line can be embedded into the system. Fastening occurs using special frames.
Unit performance characteristics
Please note the following factors:
- You should not buy a unit whose performance is much greater than the value you need. In this case, excessive energy consumption is possible. For a private home, a device with a pressure of 3–4 meters is sufficient.
- It is worth choosing a model from proven and well-established manufacturers in the market.
- When purchasing a device, you should consider the temperature environment, to avoid freezing, which will lead to malfunctions.
- The larger the diameter of the pipeline, the more powerful the pump will be required.
If the unit is not intended to be used continuously (seasonally or as a feed to the main system), you should not attach great importance to its power. The load on it will be small, which means it makes no sense to overpay.
- the device must be installed on a pipeline of the diameter for which it is intended. Otherwise, you will have to sacrifice pressure;
- The presence of a timer will allow you to set the operating mode of the pump, and it will automatically turn on during the highest fluid consumption.
Modern models are equipped with special sensors that allow you to save water and energy: thermostat, timer, auto settings.
Cost calculation
The circulation apparatus can be purchased from 5,000 rubles and above, depending on technical characteristics and manufacturer's brands.
Grundfos brand pumps - prices in the range of 8000 - 15000 rubles at a pressure of 1.20 mwst., DAB 7000 - 9000 rubles at a pressure of 1.60-5.70 mwst., Wilo 5000-7000 at a pressure 2-6 m.v.st. respectively. The price of energy consumed is approximately 720 rubles or 200 kW per year.
These small expenses will allow you to use hot water at any time, heat the room and even warm up the water in the pool.
The use of a circulation pump can significantly reduce the excessive consumption of water, because now you don’t have to wait and drain the water until it warms up.
Learn more about the circular pump by watching the video:
Special functions allow you not only to save liquid consumption, but also the use of electricity: various thermostats, timers, sensors allow you to regulate the operation of the device, turning it on and off at the right time.
To ensure comfort and coziness indoors, it is impossible to do without hot water, and this applies not only to residential buildings, but to enterprises, offices and other institutions. Used for circulation special system with a device that performs its task at the highest level.
We are talking about a pump that is available on the market in a wide range. Its job is to circulate liquid in a closed circle.
Peculiarities
This unit allows you to quickly get hot water from the tap; without it, everything would happen much slower. As for costs, they do not exceed the cost of a conventional boiler from well-known manufacturers.
Before purchasing equipment, you should study its features, main technical and operational characteristics, analyze the advantages in order to make right choice. A DHW circulation pump is a device that moves water in a pipeline. In addition, the device is designed to increase the pressure in the main system to a certain level.
Such units are installed in multi-storey buildings in order to receive liquid from the tap at the same temperature. But it should be noted that the pump is also required to maintain pressure if it has to be disassembled during peak times. If several taps are open at the same time, it is necessary to maintain the same pressure and temperature everywhere. Distinctive feature The pump is small in size, so installing it is quite simple, and you can handle this task yourself without outside help. The recirculation unit does not consume a lot of electricity, so it can be called economically beneficial. The equipment is manufactured in accordance with all necessary standards.
Device
The recirculator works on the same principle as the pumps used in heating systems. The main purpose of the installation is to stabilize and increase the pressure of the water supply, which is not enough. A closed equipment system consists of the following elements:
- storage capacity;
- control and shut-off valves;
- pumping device;
- circuits that connect to water points.
The container is filled with hot water. The temperature range can reach +100 degrees. The pump must create the required pressure, thereby forcing a certain volume of liquid to circulate constantly. As soon as the consumer opens the tap, he receives hot water, which is supplied under pressure. This allows you to use the bath and shower.
As for the cost, it all depends on the model and manufacturer, prices start from 100–115 euros and above.
Glandless rotor pump
There is a wide selection of models of such equipment on the market. Many devices have an electric motor. All moving elements of the mechanism are completely in the aquatic environment. This “wet” design has a number of advantages, such as:
- There is virtually no need for maintenance;
- equipment operates without unnecessary noise;
- consumes little electricity.
The water unit consists of a sleeve, a motor stator, a pump housing with two holes for mounting, bearings and an impeller with blades. The parts are made of stainless steel and therefore do not corrode. A wet rotor has a number of features, the first of which is low efficiency. It is important to note that the liquid must be clean without additional impurities, so filters will need to be installed. This device does not tolerate dry running. It should be constantly in the aquatic environment, then the boosting effect is preserved.
Dry rotor device
Such equipment requires the use of conventional oil lubrication to reduce friction in the bearings. The engine chamber is separated from the liquid by a seal on the shaft. As for the case, it is cooled by air. The features of the unit include its large size and weight. This provides more power, so often such a device is used in industrial areas. The efficiency is high, it makes noise, so the unit is almost never used in individual houses. You can install such a device anywhere, which makes the task easier.
Control method
Keeping hot liquid circulating at all times is acceptable, although it is not always economically justified. Many will agree that there is not always a need for such water, so it is not necessary for the pump to work non-stop. If the pipes are laid out correctly, as well as equipped with thermal insulation, then the liquid will not immediately cool down. As far as monetary costs are concerned, this will not affect them since recirculation pumps are inexpensive to maintain.
The control method can be by timer, that is, schedule, and by temperature sensors.
How to choose?
To choose the right pump for domestic hot water, you need to understand the parameters and characteristics, as well as listen to the recommendations of specialists who will help you make a profitable purchase.
The main indicators include the power of the unit. This characteristic indicates the amount of electricity that will be consumed by the device. At the same time, power also affects the performance of the device, which means the amount of water moved through the pipeline in a certain period of time. The operation of the device is influenced by various factors.
It is worth paying attention to the height and length of the pipeline, it should be taken into account hydraulic resistance, as well as additional systems connected to the site. An important aspect is the pressure of hot water supplied from the tap and even its quantity.
You cannot purchase a unit whose performance exceeds the required value. In this case, excess energy consumption will occur. Models should be considered only from trusted and well-established manufacturers.
It is important to study reviews, find out customer opinions, and compare characteristics. If you need a pump to install it in a bathhouse, you do not need to take a powerful unit, since it will not be used constantly. It is enough to pay attention to compact devices with a wet rotor; of course, it all depends on the water tank, which must be filled.
An important point is the ambient temperature where the equipment will be installed. Make sure that the pump is not exposed to freezing, otherwise its operation will be adversely affected.
The power is determined by the diameter of the pipeline. The larger it is, the stronger the device will be. If you plan to use hot water seasonally, then you should not explore such options.
Household appliances are in greatest demand and are optimally suited for use at home. They have special sensors to save water and energy, a timer, thermostat and auto settings are installed. Please note that a dry rotor pump is equipped with a fan for cooling, which produces additional noise.
The mini-device is suitable for a small apartment where a large amount of hot water is not required. It is capable of pumping liquid and feeding it into the system without any problems.
Before you start looking for pumping equipment, you need to correctly calculate the device parameters. Only after this can you decide on a purchase and invest wisely. Such data includes the workload of the water supply system, as well as sufficient flow strength. An important point is to take into account the number of taps that can be turned on simultaneously. It is necessary to create the same pressure of the circulation pump so that the pressure remains constant everywhere.
If we talk about the average water consumption at one point, it is about one hundred and eighty liters per hour. If a house or apartment has two bathrooms and a kitchen where taps are located, the best choice would be to install a device with a throughput capacity of at least 0.7 cubic meters per hour. We must not forget about hydraulic resistance common system. Pressure and pressure are affected by the length and height of the pipeline, so these indicators also need to be clarified. A water column of 0.6 meters uses 10 linear meters of contour. The manufacturer always adds technical documentation to each model and type of pumping equipment, so it is worth studying all the indicators and descriptions.
Thanks to such calculations, it is possible to obtain the average heat consumption of hot liquid through a circulation pump, which will help you quickly make a choice and facilitate the purchase. Of course, an industrial-type device is suitable for pumping water at a large enterprise, but slightly different models are suitable for a home.
Today, calculations can be made online thanks to electronic calculators, where the corresponding indicators are entered, which speeds up the solution of the problem. If a pump is selected for an apartment building or a cottage with a large area, such calculations are carried out only by qualified specialists from design and installation organizations, since they are responsible for the performance of the entire system.
To correctly install the pump in a hot water supply system, you must first study the instructions in detail and strictly follow the manufacturer’s recommendations. In addition, building codes are important and must be heeded.
To complete the installation you will need to complete the following steps:
- the installation location of the circulation device is selected. The module must be installed on the return line, which will prevent air from entering, which in turn will lead to a decrease in the functionality of the entire system;
- between the pump and the storage tank must be mounted check valve;
- shut-off valves are installed before and after the station, their number depends on needs;
- A UPS is used for connection. As soon as the power is turned off, it will ensure that the device operates in autonomous mode. The duration of its operation ranges from several hours to a day.
Lack of hot water pressure when opening a tap is a fairly common phenomenon found in private and apartment buildings. One of effective means solution to the problem - a circulation pump for hot water.
Installation of pumping equipment for hot water supply, according to existing building codes, is optional for premises with a heated area of up to 500 m²; in practice, installation may be required even if there are 2-3 separate hot water points.
Why do you need a DHW pump?
The DHW circulation pump is designed to create pressure and constant circulation of water in domestic water supply systems. After opening the tap, you have to wait a long time for the water to become hot, and the further the water supply point is located from the DHW input, the more time this requires. The pressure in the system does not always match even minimum requirements, not allowing you to wash properly.Circulation pumps for domestic hot water are installed for the following purposes:
- Ensure stable pressure in the system– for this, hot water is diverted into a special buffer tank, after which it is supplied under pressure to water supply points.
- Provide instant hot water supply– the circulation pump for hot water supply is connected to a closed pipeline. Water is constantly in motion. Thanks to circulation, the cooled liquid mixes with the heated one. As a result, immediately after opening the tap, hot water is supplied to the consumer.
What is the difference between circulation pumps for heating and hot water supply?
The use of a circulation pump in a hot water supply system has its own characteristics that differ from the use of stations in water heating circuits. For this reason, the circulation equipment for each system is not interchangeable.The differences between circulation pumps are as follows:
- Performance– heating pumps have a larger power reserve, which is simply meaningless for DHW. If necessary, you can install circulation equipment for heating systems on water, but not vice versa. Some manufacturers offer twin pumps with two electric motors specifically for this purpose. The module is simultaneously connected to DHW and heating.
- Housing – another difference between models for heating and pumps for hot water supply is the material of the housing. In hot water supply stations, the structure is made of brass, covered with a thermal insulating casing on top. Cast iron appliances are used for heating.
- Coolant temperature. If you pay attention to the technical characteristics of the pumps, you will notice that the equipment for hot water supply can be operated at an operating fluid temperature of no more than 65°C. In heating systems, the coolant heats up to 90-95°C.
How does a circulation pump work in a hot water system
The operating principle of the DHW circulation pump is almost identical to that used in heating systems. The purpose of the installation is to increase and stabilize the missing water supply pressure.Circulation pumps in domestic hot water systems of private residential buildings operate as follows:
- A closed hot water system is installed, consisting of: a storage tank, shut-off and control valves, pumping equipment and a circuit connected to water distribution points.
- Hot water is drawn into the container. The pump creates the necessary pressure, forcing a certain amount of water to constantly circulate in the pipeline circuit.
- When the tap is opened, the consumer immediately receives hot water under pressure, sufficient to take a shower, quickly draw a bath, etc.
Along with this, there is a danger of dry running. The coolant plays the role of a lubricant. Without lubrication, bearings instantly fail.
Circulation pumps used in hot water supply systems of multi-storey residential buildings are often called booster pumps, since their task is mainly to create sufficient pressure in the water supply system.
How to choose a pump for a domestic hot water system
Selecting a hot water circulation pump can be difficult, even for a professional. Several factors are taken into account when choosing:- Technical characteristics of pumping equipment.
- Additional functions.
- Manufacturer company.
Electronically controlled models are considered the most convenient to use. The pump is supplied complete with a thermostat built into the housing. The automation independently examines the intensity of water consumption and, based on the results, selects the required operating mode. The on-off timer allows the module to autonomously switch to “night mode” to save energy.
The average pump life is 7-9 years. In practice, the station, under moderate loads, is guaranteed to operate for at least 10 years.
How to calculate the pressure of a DHW pump
An accurate calculation of pump parameters can only be made after obtaining the following data:- Congestion of the water supply system.
- Sufficient flow force.
- The average water consumption for a point taken into account is 150-180 l/hour. Accordingly, in a house with two bathrooms and a kitchen, you will need to install a pump with a capacity of at least 0.7 m³/hour. When making calculations, it is necessary to take into account the hydraulic resistance of the hot water supply system, which for a private house is in the range of 0.1-0.2 atm.
- Pressure - the height and length of the water pipeline also affects the calculations. It is generally accepted that for every 0.6 m of water column there are 10 lm of water circuit. If the technical documentation of the pump provides pressure parameters of 4 m, this is enough for a water circuit with a length of 60 running meters.
Calculations when organizing hot water supply with a circulation pump in apartment building and large-area cottages must be carried out by a design and installation organization that will be responsible for the operability of the system.
Which companies produce pumping equipment for hot water supply?
There are about a dozen different companies that manufacture pumping equipment specifically for hot water supply. The cost of the pump varies depending on the manufacturer and technical characteristics, from 5 to more than 100 thousand rubles. It is not recommended to purchase cheap modules, as often low-quality fakes are obtained due to the low cost.The best manufacturers of pumps for hot water supply are:
Domestic manufacturers place their main emphasis on the production of equipment for heating systems.
Installing a circulation pump in a domestic hot water system
Installation of the pump in the domestic hot water system must be carried out in accordance with the manufacturer’s recommendations and existing building codes. Installation work is carried out as follows:- Installation location of the DHW circulation pump - the module is mounted on the return line. This arrangement prevents air from entering the station - airing leads to a decrease in the performance of the system. For this reason, the pump should be installed exclusively on the return water supply.
- A check valve is installed immediately after the pump and in front of the storage tank. Shut-off valves must be installed before and after the station.
- The connection to the mains is made via a UPS for power supply. After a power outage, the uninterruptible power supply continues to ensure autonomous operation of the equipment for from several hours to a day. (how to choose the right UPS for pumping equipment,).
- To distribute pressure evenly, a complex DHW control system is installed, including several distribution manifolds and special pressure reduction valves.
- It is prohibited to start the electric motor at idle speed. After the pump has been installed in the hot water supply system, the water circuit is filled, a test run is performed and the functionality is checked.
- Maintenance – wet rotor pumps have a simple design, so they do not require inspection or repair during their entire service life. The filter will need to be cleaned and replaced from time to time. The frequency of maintenance of a pump with a dry rotor is once every 2 years. During the work, the lubricant is replaced and the housing is cleaned.
The circulation pump is one of the most important components of a heating or hot water supply system. After all, without this unit there will be neither pressure in the water supply nor circulation of the coolant in the wiring. Therefore, when deciding which circulation pump for hot water to choose in a particular case, you need to take into account many nuances that influence the selection process of a particular model.
And in this article we will introduce you to these “nuances”, based on which you can choose a really decent pump.
The most important structural difference between one model and another is the type of rotor of the unit.
And on this basis, all circulation pumps are divided into units:
- With a “wet” rotor
Wet rotor circulation pump
Moreover, circulation pumps with a “wet” rotor involve placing the “pressure part” of the unit - the rotor and impeller - in the pumped medium. That is, hot water plays the role of both a cooling medium and a lubricant. Therefore, wet-type units work for a very long time and practically do not make noise. And the "wet" pump is very cheap and does not need maintenance. That is, a unit with a wet rotor can simply be “set and forgotten.”
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But with all the advantages, “wet” pumps also have their disadvantages, among which we need to highlight a very low efficiency (up to 40-45 percent) and limited positioning of the device (the pump can only be mounted in a horizontal position).
Therefore, “wet” pumps are purchased by owners of domestic water supply and heating systems installed in small houses. Such a pump is not suitable for anything more.
- With a dry rotor
Circulation pump with dry rotor
In turn, circulation pumps with a “dry” rotor involve separation of the “power plant” from the pumped medium. That is, the rotor of the unit remains dry, so a problem arises with both lubrication and cooling. Moreover, the first problem is solved during periodic inspection, and the second - with the help of a built-in fan.
As a result, “dry” pumps are “more expensive” than wet ones both at the purchase stage and during maintenance. However, all the above-mentioned efforts will be rewarded with almost twice the productivity compared to “wet” pumps, which reaches up to 70 percent.
Therefore, “dry” pumps are purchased for integration into industrial and municipal heating and hot water supply systems.
Selecting a DHW pump based on performance characteristics
The main purpose of the circulation pump is to maintain the optimal speed of coolant flow through the wiring, at which it would be possible to record the temperature of the liquid in the “return”.
Therefore, the key operational criteria influencing the choice of a circulation pump include the following parameters:
- The value of the pressure, measured in the height of the water column - the pressure in the distribution, and therefore the return temperature, will depend on this criterion.
- The flow rate value is calculated using a special formula as a quotient of the power of the heating installation (divisible) and the temperature difference in the pressure pipe and return pipe (divisor).
- The heat transfer value of a heating system, calculated based on the area of the heated room and the estimated heat losses.
Moreover, the selection process looks like a comparison of all the parameters described above in order to compare the pump pressure with the heat transfer and flow rate of the heating system. As a result, only an experienced designer or heating engineer can extract a specific recommendation from this data.
Selecting a pump by model popularity
It should be recognized that design differences and expected operational characteristics will “help” only a pressure equipment specialist to select a pump. And they just confuse the average consumer. Therefore, for non-specialists, the best selection criterion is rather the popularity of the model, which will be “more understandable” than any technical specification.
And from our point of view, buyers of pumps for hot water supply systems should pay attention to the following models of circulation units:
UP Grundfos domestic hot water pumps
This series belongs to the "wet" type of pumps. Therefore, UP Grundfos works absolutely silently, but with low productivity. In addition, the pumps from this series have only one speed. As a result, UP Grundfos should only be purchased by owners of domestic heating systems assembled not in the boiler room, but directly in the house.
The advantages of the UP Grundfos series include the absence of the need for maintenance and minimal risk of lime deposits forming on the inner wall of the pressure unit. Grundfos has also provided the possibility of dismantling the unit without disassembling the pipeline.
That is, we have before us an almost ideal household model of a circulation pump, with many advantages.
Another “wet” unit, designed to maintain pressure in both heating networks and water supply systems (both hot and drinking). Moreover, this Wilo-Star-Z model is supplied as a mechanical shut-off valves(check valve at the outlet and ball valve at the inlet), and electronic filling (timer, thermostat, display, etc.).
As a result, the Wilo-Star-Z model can be used both in conventional heating systems and in high-tech heating networks integrated into the “smart home” system. This pump also has a recognition system for the thermal disinfection function used when working with drinking water.
Pump VortexBW 152 R1/2″ oT
This pump is produced by the German company Vortex. Moreover, the pragmatic Germans, who simply do not know how to make bad equipment, endowed the model with not only noticeable performance, but also amazing maintainability. The pump can be disassembled without much hassle and without the need to dismantle the unit itself. Therefore, the VortexBW 152 R1/2″ oT model can be descaled without removing it from the pipe.
In addition, 152 R1/2″ oT operates absolutely silently and differs from similar competitors’ products in its very modest dimensions. Therefore, in everyday life, this model is simply irreplaceable.
Pump ESPA RA1-S 25-60
The ESPA RA1-S 25-60 pump is another “wet” type unit intended for ventilation and air conditioning systems. The main difference between this model and similar proposals lies in the possibility vertical installation. Moreover, ESPA RA1-S 25-60 can be used in both hot water supply systems and cold water supply lines.
However, this pump cannot pump flammable liquids and water heated to a temperature of 120 degrees Celsius. But in domestic heating networks, this model has proven itself as an economical and productive pump, with which you can solve any problem.
