Pressure in the water supply system of a private house: specifics of autonomous systems + methods of normalizing pressure

The installation of an autonomous water source on the territory of a private household or at a dacha does not mean that this water can be used comfortably, and that all hydraulic appliances and plumbing fixtures will turn on reliably and work reliably.

It is also necessary to ensure that the pressure in the water supply system of a private house is within the optimal values, with the pressure required for domestic and economic needs. And how to achieve this will be discussed below.

Characteristic features of autonomous water supply systems

One of the most important characteristics of a water pumping system is water pressure. Not only the pressure in the tap, which makes it possible to carry out normal hygiene procedures without problems, but also the performance of all water-consuming devices and equipment depends on it.

It should be taken into account that the functioning of an autonomous water system differs from the centralized water supply of high-rise buildings.

First of all, an independent water supply system is a complex of specific measures, without the implementation of even one of which the scheme may not work at all, or may not work as it should

There are some peculiarities in maintaining a consistently optimal pressure of water extracted from autonomous source.

The system of independent use of water supply sources for a country house includes interconnected elements:

1. Pipelines, fittings, pressure gauges.
2. Submersible or a surface pump to lift water from a source.
3. Pressure-increasing pumps, and there may be several of them, or a pumping station with a hydraulic accumulator to accumulate a reserve of water for the purpose of its further uninterrupted consumption.
4. A relay that turns the pump on and off, if necessary.

Unlike residents of high-rise buildings, the owner of a private house has to resolve issues related to the correct and effective interaction of all these elements on his own.

Feature #1 - raising water from a well

Water is collected and transported directly from the water supply source.

And there may be several options here. But which one to choose mainly depends on the complexity and cost of raising water to the surface. The most expensive are an artesian well and a well.

For the purpose of providing personal households or cottages with water, as a rule, relatively accessible sources are selected - a water well or an ordinary mine well.

The first option is due to the need for deep drilling, using special equipment, the second is due to manual labor.

Well needle, or Abyssinian - the easiest source for a DIY device and the least expensive source of equipment.

Each of these options has its pros and cons, and the choice depends not only on the price and complexity of the work, but also on the specific geological conditions of the area.

Feature #2 - water intake flow rate

The performance of the water supply system and the use of pumping equipment in it depends on the flow rate of the water source.

Correct calculation of flow rate allows you to rationally use this source and competently approach the issue pump selection.

The greater the ratio of the maximum possible volume of water for extraction from a well or well to the unit of time during which the source will be exhausted, the higher the water intake productivity is considered and, accordingly, the more powerful the pump should be.

To determine the flow rate of a source, two water level indicators are used:

1. Static - the length of the section from ground level to the water in the source at rest.
2. Dynamic — the distance from the surface to the established level of the water surface when the pumping unit is turned on.

If the amount of water pumped out from the source is stably at the level of its replenishment, then we can say that the water intake capacity corresponds to the pump power. With a good flow rate of the source, the difference between these two levels should not exceed 1 meter.

The flow rate of the source is determined as the ratio of the pump performance - Vl, to the difference between the dynamic and statistical levels, multiplied by the height of the segment L - from the filter to the water level at rest of the source

The pump capacity should not be higher than the flow rate of the source. Otherwise, a situation is possible in which, having pumped out all the water, the conventional pump will continue to run dry. And this threatens its failure.

It is recommended to install the pump away from the filter, but so that there is always a water level above it of at least 1 m.

Feature #3 - transporting water to consumers

The use of an autonomous source dictates the need to install pumping equipment not only to lift water from the aquifer, but also to create a pressure sufficient to pump it through pipelines and subsequent distribution throughout the house at various levels.

Do not forget about irrigation and fire extinguishing systems, the operation of which must be ensured with appropriate pressure.

When choosing pumping units, it is necessary to take into account the pressure-reducing hydraulic resistance of the pipes, which directly affects the speed of water flow. And the longer the communication route from the source to the home and the end consumer, the greater this resistance becomes.

Additional barriers to water that reduce pressure in the system are pipe turns, fittings of the pipeline system, filters and shut-off valves

Therefore, for an autonomous water supply it is necessary to take into account not only the size of the worker, i.e. pressure recorded under standard conditions in the water supply system of the house, but also the calculated one - the maximum excess pressure.

Based on the calculated pressure values, water pipes with appropriate diameters and wall thicknesses are selected. All this affects the reliability, efficiency and durability of the decentralized water supply system.

Basic standards for water pressure

The pressure values ​​in the water supply system, both cold and hot water, are regulated by a special set of rules and SNiPs. There are no separate standards, applicable only to private houses, for water pressure at the entrance to the house or at the points where it is dispensed.

According to general rules, the lower limit of pressure at the level of the first floor of a house should be 1 atmospheric unit or 1 bar.This value corresponds to the pressure required to create a 10-meter column of water.

If the house has several floors, then to calculate the input pressure, 4 m of water column or 0.4 atm is added to each floor.

So, for example, for a 2-story cottage, the minimum pressure at the entrance to the house will be 10 m + 4 m on the 2nd floor = 14 m or 1.4 atm

You need to know that equipment, devices and sanitary equipment working with water have individual standards that define minimum indicators water pressure, which ensures the normal functioning of these devices.

Sanitary engineering:

• 0.2 atm - washbasin, toilet;
• 0.3 atm - bath, shower, bidet;
• 0.4 atm - jacuzzi and hydromassage equipment.

Appliances:

• 1.5 atm - dishwasher;
• 2 atm - washing machine.

Other water consumers:

• 1.5 atm - fire extinguishing system
• 2 atm - heating boiler, taking into account the parameters of the heating system;
• 3.5 atm - watering system.

In order for the equipment to operate at the limit of its characteristics and function normally, it is necessary to add another 0.5 atm to the nominal passport values.

You can determine the pressure in the water supply system using pressure gauges. These devices can be installed at the entrance to the house, and they are also equipped with pumping stations, which will be discussed below.

Monitoring the water pressure in your home is carried out according to the readings of pressure gauges, which must be equipped with the water supply system

Methods for increasing pressure

The construction of a water pipeline, like any other construction, begins with a project.Therefore, it is preferable to work out and calculate the issue of equipping the system with the necessary pumping and other equipment to maintain optimal pressure in it at the design stage.

If a decrease in pressure in the water supply system occurs during its operation, first of all, it is necessary to establish the possible causes of the malfunction.

To do this, an audit is carried out inside the circuit and the main elements of the water supply scheme to identify defects or miscalculations.

These may include:

• incorrect selection of pumping equipment based on performance;
• design errors made during installation of the system;
• leaks and fistulas in the pipelines themselves or at their connections;
• reduction in pipe clearance due to deposits formed as a result of long-term operation;
• contamination of filter elements;
• malfunction of shut-off valves.

To forcibly increase the water pressure in a private water supply system, both newly built and existing, there are several methods.

Method #1 - Using a Circulation Pump

This method will give the desired effect if the pressure in the water supply needs to be increased by 1-2 atm. To implement it you will need to purchase additionally circulation pump.

The principle of operation of such a unit is to create pressure differences in the pump chamber due to centrifugal force, as a result of which water enters the system through the outlet of the pump with increased pressure. The process occurs in a continuously repeating cycle.

For this, conventional circulation pumps are used. They can be mounted both at the entrance to the house or the general water supply riser, and directly in front of water consumers

The main characteristics that you should pay attention to when choosing such a device are:

• water pressure provided at the outlet;
• ability to work in manual and automatic modes;
• noise component;
• rotor type.

Based on the operating principle of the rotors, the devices are divided into wet and dry type pumps.

In the first case, the movement of water in the system is realized due to the rotating blades of the impeller, which is mounted on the rotor shaft. The working elements of the pump are cooled and lubricated naturally due to the water flow.

This feature gives the device great advantages over other types of pumps.

The quiet operation of a wet-rotor flow pump makes it possible to install the device inside bathrooms and kitchens without experiencing the inconvenience associated with noise during constant operation

The efficiency of a unit with a wet rotor is not very high - 45%, but for domestic use this device is quite a worthy option.

In the second option, a more efficient dry type pump is installed on the common line.

The pump motor is mounted outside the pipe and has no contact with the liquid. Cooled by air. Such units may differ from each other in the type of connection to the engine and its installation location.

The efficiency of a pump of this type is much higher - about 70%, which makes it advisable to use it if it is necessary to create a higher pressure in the system and if the flow pump performance is not enough.

Having chosen a dry type unit, you should take into account that it will not only be larger in size, but also higher in noise level during operation.Therefore, for the installation of such pumps, it is advisable to allocate a separate room, isolated from living rooms.

As a conclusion, for a slight increase in water pressure, including in the supply to a separate household appliance or sanitary equipment, it is advisable to use a less powerful flow-through unit.

Installing circulation pumps on a water supply system is not very difficult. The main thing is that the installation is carried out taking into account the direction of operation of the impeller indicated on the device - in the direction of water movement.

In the modern market, pumps from the brands Wilo, Grundfos, Oasis, and Gilex are in demand. A large number of offers allows you to choose a unit with the desired characteristics in terms of pressure, performance, dimensions, noise and other indicators at an affordable price.

The pipes of all devices are unified for installation on Russian water supply networks.

Method #2 - water pumping station equipment

The equipment of a home pumping station is more expensive, but modern and will definitely solve the issue of providing a private or country house with water at optimal pressure.

Such a station can lift water from an autonomous source and uninterruptedly deliver it to all water distribution points, as well as ensure an increase in pressure in the system to optimal values

The water pumping installation includes five main elements:

1. Electric motor.
2. Self-priming pump.
3. Storage tank.
4. Pressure switch.
5. Check valve.

To create a supply of water, a regular storage tank or a factory one can be included in the system. hydraulic accumulator membrane type.

Pumping station with tank — this option is somewhat outdated and not entirely convenient due to the need to have a very large capacity in the station. And the pressure of water, which is drawn by gravity, will depend on the height of the tank.

This entails such a problem as choosing a place to place a water tank on the attic floor or a floor higher than the water consumers. In addition to installation inconveniences, the risk of flooding of the rooms below also increases in the event of any malfunction.

Despite these disadvantages, such a system for increasing pressure in the water supply system has been used for a long time in private homes, and is also widely used in the construction of new water supply systems.

The equipment diagram of a station with a conventional tank is simple. The tank, installed at the highest possible height, is connected to the water supply through a pump

The filling of the container during water dispensing is monitored by a relay, which automatically starts the pump when the level drops and, accordingly, the water pressure in the tank drops to a certain value. When the water supply is replenished, the pressure in the tank increases and, having reached the maximum set value, the pump turns off. The cycle repeats.

Home station with hydraulic accumulator. This is more advanced and modern equipment in an autonomous water supply system. The station kit must include a hydraulic accumulator, another name is a membrane tank.

Diaphragm tank design. The sealed housing consists of two chambers separated by an elastic membrane made of durable rubber - butyl. In one part of the tank there is air under pressure, in the other, membrane, water from the water supply system is accumulated

The membrane material is sanitary safe and, according to hyena standards, suitable for storing drinking water.The principle of operation of the hydraulic accumulator is based on the ability to increase its volume under the pressure of water pumped into the membrane, thereby increasing the air pressure in the second chamber.

When the pressure increases to a threshold value, the relay turns off the pump. A decrease in pressure in the chamber when drawing water forces the relay to restart the pump.

The membrane tank has an air valve, the pressure on which should be 1.5-2 atm. The valve is designed like a regular car nipple, which makes it possible to manually regulate the pressure in the air compartment.

Advantages of a pumping station with a hydraulic accumulator:

• possibility of equipment at any level of a private house;
• increasing the service life of the pump;
• creating relatively equal pressure in the water supply;
• accumulation of liquid reserves in case of emergency power outage.

When installing a pumping station, it is advisable to place the hydraulic accumulator in such a way that there is easy access to it, allowing for maintenance or repairs without draining water from the system.

Read more about how to choose a pumping station for a private home Further.

Stabilization of pressure in the water supply system

To operate the water supply system of a country house in a consistently equal pressure mode, the presence of only a membrane tank in the circuit is not enough and the likelihood water hammer remains big.

Water hammer very often causes failure of pipelines, pumping equipment, check valves and other expensive equipment

Another reason that justifies the need for forced stabilization of water pressure is the possibility of increasing it at various water points of the system while they operate simultaneously. For this purpose you can use a frequency converter.

For example, in the absence of a device that equalizes water pressure, if one person takes a shower and another waters the garden at the same time, the water pressure will be divided in half.

Advantages of a frequency converter:

• the water pressure is maintained stable throughout the entire time of water consumption;
• the pump operates in smooth start and stop modes, which increases its service life by 1.5 times;
• protection of the pump from dry running;
• sleep mode significantly saves energy;
• possibility of reducing the volume of the membrane tank by almost 10 times.

In addition to saving space, a small tank eliminates unpleasant odors associated with stagnant water. Modern pumps and stations can be purchased with a built-in frequency converter.

A modern device, a frequency converter, which makes the water supply system intelligent, can solve the problem of unstable water pressure, protect pipes and equipment from water hammer, and prevent sudden voltage drops when turning the pump on and off.

But it is quite easy to integrate a separately purchased converter into the water supply system. The main thing when selecting it is to take into account compatibility with such characteristics of existing equipment as power, supply voltage and current.

Conclusions and useful video on the topic

Video, the author of which shares advice on increasing water pressure in a private home using a self-built pumping station with a storage tank:

Video about the nuances of connecting a hydraulic accumulator to the water supply system of a private house and adjusting the air pressure in it:

Video describing the advantages of a frequency converter in a water supply system with operating instructions and a description of its operating modes:

Normal water pressure in an autonomous system is an essential condition for comfortable and reliable operation of the water supply system. Living in your own home or country house dictates the conditions under which the most ordinary person must be an expert in many matters.

Knowing the simple basics of the theory of water pressure in an independent water supply system and following the tips outlined on how to make it stable will give only positive results. This will allow you to avoid possible miscalculations at the planning stage and when carrying out work on installing an autonomous water supply system, and will help you correctly determine the purchase of the necessary equipment.

If you want to ask a question about the topic of the article or have valuable knowledge that will help normalize the water pressure in the system, please leave your comments in the block below.