In order for devices connected to the water supply system to function normally, it is necessary to maintain a certain level of water pressure in the water supply. This indicator affects the flow of water into the mixers. If there are errors in the calculations, water may flow in a thin stream or disappear altogether after turning on other mixers.
Many people do not know how water pressure is measured. It is calculated in “bars”. If this indicator is below normal, it will not be possible to use the jacuzzi or massage shower modes, and household appliances connected to the system will break down much more often.
Water pressure standards
What is the normal pressure in the water supply?
Water pressure in a water supply system is measured in bars, but sometimes this value is indicated in atmospheric units. For clarity, under a pressure of 1 bar, water can rise to a height of up to 10 meters. If we convert them into atmospheres, then 1 bar is equal to 1.0197 atmospheres.
In cities, the water pressure in the water supply system is 4 atmospheres. This is enough to supply multi-storey buildings. The range is established according to special documents and SNiPs. For cold water these figures range from 0.3 to 6 bar, and for hot water – up to 4.5.
As for owners of private houses, they need to calculate these indicators themselves. If an autonomous system is installed in the house, it increases the pressure to 10 bar. However, for the operation of household appliances and all water supply points, 1.5-3 bar is sufficient in a private house. Such pressure indicators are available to most pumping stations. This range should not be greatly exceeded. Otherwise, the connected devices will not work correctly and quickly fail. The maximum permissible water pressure in the system of a private house is 6.5 bar.
A pressure of 10 bar can only be withstood by specialized equipment installed in artesian wells. Conventional connecting units and jumpers for cottages will not be able to withstand such loads and will leak.
It is worth considering the established pressure indicators for certain devices. Without compliance with these indicators, they will not work:
- washing machine – 2 bar;
- fire safety system – 1.5 bar;
- jacuzzi – 4 bar;
- watering lawns – 4-6 bar;
- mixer in bathtub and shower stall - minimum 0.3 bar.
According to the majority of home owners, a level of 4 bar is the most optimal for providing all points of water consumption. At the same time, it is not critical for fittings and various connecting units. Next, you'll learn how to measure your water pressure so you can plan your next steps.
Classification of pressure gauges and operating principle
Digital water pressure gauge
Depending on the operating characteristics of the pressure measuring device, they are classified into the following types:
- Piston. They include a cylinder containing a piston. During operation, the medium acts on one part of the pump, and the load presses on the other. The slider moves by moving the arrow. It shows a certain value on the instrument scale.
- Liquid. They contain a tube with liquid and a movable plug. When using such a device, the working medium presses on the plug, changing the level of liquid in the tube. The arrow of the device is set in motion.
- Deformation. Inside such products there is a membrane, which, when deformed, activates the pointer above the scale.
Modern pressure measuring devices are divided into mechanical and electronic. In the first case, the design of the device is as simple as possible. The electronic pressure gauge contains a contact assembly that can more accurately measure the pressure of the working medium. Such devices have found wide application in industry. They are used as exemplary models for testing pneumatic units and adjusting regulators in various automated systems. Many electronic pressure gauges store data on peak pressure values over a certain period of use.
Depending on the characteristics of the work, the devices are:
- Stationary - installed only on certain units. It is not possible to dismantle such pressure gauges. Often a water pressure regulator is used together with them.
- Portable – can be installed on different units and used in various systems. A distinctive feature of the models is their small size.
Many of the pressure gauges are used in heating systems of country houses and apartments in multi-storey buildings. Others are used to service industrial facilities.
How to measure water pressure
Typically, water supply pressure is measured using an already installed pressure gauge. It should be located in front of the entrance to the system and record the flow of water entering it. If it is not there, then there is one proven way to find out the pressure. For this you will need:
• pressure gauge (with scale up to 6 bar); • thread extension; • special adapter from 1 to 2 inches; • plumber's tape.
First you need to attach the pressure gauge to a thread extension and a special adapter. This must be done using plumbing tape. Next, you need to check the tightness of all connections. Nothing should move, the structure should be solid. Afterwards, in the bathroom, unscrew the nozzle from the shower hose. Secure its end into the device. Once everything is connected, turn on the water and switch the shower/tub positions several times. This will remove excess air from the system. Now you can take measurements. If water begins to ooze out of the structure when air leaves the structure, it needs to be strengthened more securely by tying it several more times with plumbing tape. To get the result, you need to turn on full pressure from the mixer. The pressure gauge should immediately show the water pressure.
This is a universal method with which you can check the pressure in apartments and private houses. Instead of an adapter and thread extension, you can use a hose that fits the shower hose. Reasons for the decrease in pressure
Many people wonder why there is low pressure in the tap of the water pipe. There are several reasons for this:
- The most popular reason is that the pipe is clogged with something. If the water is of poor quality, it can leave various sediments as it moves. This has a particularly strong effect on turns, bends and branches. When the pipes are metal, there may be accumulated rust or limescale.
- Leak. It can be caused by frequently changing pressure, poor-quality pipe connections, or defective material from which they were made.
- If a private house is connected to a central water supply system, the pressure can be reduced artificially. This happens due to debt on bills or repair work on pipeline sections.
When a house is connected to an autonomous water supply (well or well), a decrease in pressure can result from two reasons:
- Insufficient water in the well. As a result, the pumps cannot supply the requested amount of liquid.
- There is a lot of water in the well, and the pumps are not configured correctly. Because of this, they pump water, overloading the entire system. Under critical loads, the connecting nodes will not withstand and leakage will occur.
Three methods to measure water pressure in an apartment
Problems with water pressure, hot and/or cold, are more often visible to the naked eye. Poor water pressure can be seen by a weak stream of water flowing from the tap, by a long collection of water into the container, by a weak shower. Visually, the excess water pressure, which can also be in the apartment water supply, is less clear.
However, weak, non-standard water pressure can not always be seen and felt online. For disputes with management companies, as well as for connecting some household and plumbing appliances, you need to accurately measure the water pressure in the apartment. How to do this in this article.
Note: It seems to me that the problem of excess water pressure is not as pressing as lack of pressure. Therefore, the article will talk more about the lack of pressure.
About water pressure and its measurement - theory
Water pressure or its pressure, in theory, shows how much a column of water can be raised from the point of its measurement. Water pressure is measured in bars. 1 bar of water pressure can lift its column to a height of 10 meters. In relation to water pumps, a 3 bar pump, under ideal conditions, can lift water from a depth of 30 meters.
A device for measuring water pressure at any required point in a water supply network is called a pressure gauge. It is round in shape with a scale in bars and an arrow. To connect the pressure gauge, it has a special input fitting with an external thread.
Note: It is important to understand that water pressure in a plumbing system decreases as water moves through the pipe. A number of factors influence this decrease:
- Pipe wall resistance,
- Pipe turns;
- Narrowing and expanding the diameters of water supply pipes;
- Slopes and ascents of the route.
Read: What is a collector water supply scheme
Where to measure pressure
Considering the factors influencing the decrease in water pressure in the water supply system, it is important to understand that the water pressure at the entrance to the apartment may differ from the water pressure at the water intakes. Most likely this change will be minor, but it will happen.
Therefore, in order to dispute with the management company, you need to measure the water pressure at the water supply inlet to the apartment. To study the connection conditions for a new household or plumbing appliance, you need to measure the water pressure at the connection point of this device.
For example, you want to buy a washing machine that can only operate at a water pressure of 1.6 bar. Ideally, water pressure should be measured at the washing machine connection point, and not at the water supply inlet.
Three methods to independently measure the water pressure in an apartment
Let's look at three ways to independently measure the water pressure in your apartment.
Method 1, permanent
If you install pressure gauges in the inlet water supply unit, you will be able to constantly monitor the water pressure in the DHW and cold water systems. Water pressure will be measured precisely at the water supply to the apartment.
Pressure gauges are installed on hot and cold water supply, after the main shut-off valves of the apartment, after the coarse water purification filter, after the check valve, BEFORE the water consumption meters.
If the water supply system has fine filters, then it is better to place pressure gauges after them, or even better to buy thin filters with pressure gauges.
several pressure gauges in the unit
It is important to note that usually, to save space and ease of installation, pressure gauges are supplied complete with pressure reducers.
pressure gauge with pressure reducer
Note: installing a pressure reducer does not require installing a pressure gauge and vice versa. It's just convenient.
Method 2, an accurate research method to measure water pressure in an apartment
For this method, you need to make a control device to measure water pressure.
Read: Standard water pressure in an apartment’s water supply
It is not always possible to install pressure gauges in a previously assembled apartment water supply unit. In this case, as well as to measure the pressure at the water intake, you need to make a simple control device.
To make it you will need:
- Pressure gauge at max. pressure 10-25 bar.
It is important to understand here that pressure gauges may have different connecting threads.
According to GOST 2405-88, pressure gauge fittings must have metric threads (Appendix 4, Table 12): M10x1 (D scale diameter = 40 mm), M12x1.5 (D scale = 50, 60, 63 mm), more often M20x1.5 ( D scale = 100, 150, 160 mm).
If you have a pressure gauge with an M20x1.5 thread, to connect it you will need an adapter from a metric thread M20x1.5 to an inch pipe thread G½.”
For ease of connection, you may need an extension cord G½" HV (internal thread - external thread). If you have to screw the pressure gauge onto a water socket with an external thread, then you need an extension G½" BB (internal thread - internal thread).
Next, you need to assemble this device, be sure to use a linen seal or FUM tape. After assembly, you can independently measure the water pressure in the apartment in any desired place.
connecting a pressure gauge via a tee
Tip: To get a more accurate water inlet pressure, measure the water pressure at the water outlet (or pipe) supplying water to the toilet. As a rule, it is located closest to the distribution node.
Method 3, a very approximate method for measuring water pressure in an apartment
If you want to qualitatively assess the inlet pressure at the “good-bad” level, try timing the time it takes for the container to fill with water.
For example, take a 3-liter saucepan. Fill it with water when the cold water or hot water tap is fully open and measure the time for complete filling.
If the filling time of a 3-liter container is more than 8 seconds, the water pressure in the system is less than the standard 0.3 bar. In this case, the tap should not have an aerator (mesh), and the pipes should not have narrowings along the route. Narrowing the pipeline significantly increases the speed of water movement and such measurements will be incorrect.
Read: Checking the operation of water supply pipeline fittings
Note
Do not forget that excess water pressure in the system is even worse than its lack. Let me remind you that the upper threshold for cold water supply is 6 bar, and for hot water supply - 4.5 bar.
Conclusion
After reading the article, you will probably be able to measure the water pressure in the apartment yourself. Good luck.
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Source: https://elektriksan.ru/santehnika/vodoprovod/tri-metoda-izmerit-davlenie-vody-v-kvartire/
How to increase water pressure
When household appliances do not have enough water, and a thin trickle flows in the faucets, a person thinks about ways to increase the pressure in the water supply. First, you need to find out that this is not related to leaks, reduction for non-payment, lack of water in the well or clogging. Problems that can be solved using additional equipment:
- water consumption on the upper floors of multi-storey buildings;
- the system is full of water, but there is no pressure.
To correct the situation, you can purchase a pump or pumping station. They will force pump the liquid.
Units of pressure measurement in water supply: how to increase pressure to comply with SNiP
No one thinks about the water pressure in the water supply until it reminds you of itself: water flows from the tap, and it seems to be flowing well, but after a couple of minutes the flow already resembles a thin thread. Then the alarmed residents of high-rise buildings begin to find out from each other what happened to the water pressure and what it should be like under normal conditions.
How to measure water pressure in a system
The question disappears if you already have a pressure gauge at the system inlet. If not, then you will need 5 minutes of time and the following useful things:
- Pressure gauge for water.
- 1/2 inch threaded fitting.
- Hose of suitable diameter.
- Worm clamps.
- Plumbing tape.
the hose on one end on the pressure gauge, the other on the fitting. We fix it with clamps. Let's go to the bathroom. We unscrew the shower head and replace it with a fitting . We switch the water between the shower and faucet modes several times If the joints are leaking, then wrap the joint with plumbing tape . Ready. Look at the pressure gauge scale and find out the pressure in the water supply.
The hose option is universal . However, instead of a hose with clamps, you can use adapters with a 1/2- inch outlet. The required inlet adapter thread depends on the specific gauge thread ( metric , 3/8 , 1/4 ).
Pressure units: conversion table of physical quantities
There are such physical quantities directly or indirectly related to fluid pressure:
- The size of the water column . Non-system unit of pressure measurement. 1 high , exerted on a flat base at a water temperature of 4 ° C at normal density values. Used for hydraulic calculations.
- Bar . Approximately equal to 1 atmosphere or 10 meters of water column. For example, for the smooth operation of a dishwasher and washing machine, it is necessary that the water pressure be 2 bar, and for the functioning of a jacuzzi - already 4 bar.
- Technical atmosphere . The zero point is taken as the value of atmospheric pressure at the level of the World Ocean. One atmosphere is equal to the pressure that occurs when a force of 1 kg is applied to an area of 1 cm².
We use a pump
A regular pump is suitable for use both in an apartment and in a country house. It will only function normally if the system needs additional help. For example, if this concerns a private house, the main pump may not cope with its task due to the long pipeline. In this case, it must be installed in front of the collector at the entrance of the pipes to the house.
Such devices can operate in two modes:
- Manual. If you enable this mode, the pump will actively work until it is turned off manually. It needs to be monitored to avoid overheating. Otherwise, the equipment will stop working due to high temperature.
- Auto. Autonomous mode in which the pump operation is controlled by a water flow sensor. When there is flow, the equipment will work. If there is no flow, the pump will not work. Such devices are more expensive and better than manually operated models. They do not need to be monitored, they consume less electricity (they do not run idle) and are more durable.
These devices are suitable for hot or cold water. More expensive ones are universal models. Another significant difference between the pumps is the cooling system. Some are cooled using an additional fan, and those that lower the temperature using a distilled liquid (silent).
We purchase a pumping station
This is serious pumping equipment that is installed in large private houses and cottages. It is used if the pressure is critically low or there is no water in the pipeline. Pumping stations consist of a device that pumps water and an additional container. It contains the amount of liquid that the residents of the house consume during the day.
Principle of operation:
- After turning on the equipment, the pump begins to pump water into the container.
- It continues until the pressure in the tank rises to 2 bar.
- When the indicator is reached, the sensor recording the pressure sends a command to turn off the pump.
- Now the whole house system begins to consume water from the filled tank. When it is empty, the process will repeat.
Such equipment can be installed in the basement, utility room, hidden behind decorative protrusions in the bathroom, etc.
How to lower blood pressure
In addition to low pressure in water pipes, some are faced with the problem of uncontrolled pressure increases. The water supply system and electrical appliances connected to it may fail. It is necessary that the water pressure be kept within a limited range.
An inexpensive and effective solution to the problem is to install a gearbox. It should regulate the water pressure from 2 to 4 bar, suitable for hot and cold water. When purchasing this device, you need to pay attention to the direction of water flow. It can be vertical or horizontal.
With timely pressure measurements, elimination of visible causes or installation of additional equipment, you can protect plumbing and electrical appliances from breakdowns.
