Pressurization of heating. Flushing of heating systems (heat exchangers, boilers, radiators and pipes)

Everyone, sooner or later, is faced with the problem of interruptions in the operation of heating systems. The reason, most often, is that deposits, dirt, silt and scale accumulate in radiators and pipes and water cannot move freely through the system. This problem is absolutely solvable, and at home. There are various methods. However, let's take a closer look at the most common ones.

If you notice that it is getting colder in your house, this may be the first signal that you need to flush the heating system. This can be easily checked without resorting to the help of a specialist - just touch the batteries. If it is heated unevenly, or part of it is generally cold, flush. There are several more beacons that it is time to clean the pipes: uncharacteristic noise in the batteries, when the heating is started, the system warms up for a very long time.

Most often, horizontal parts of the pipe are exposed to the main pollution. According to the standard arrangement of radiators in the house, this is usually small areas and it won't be too hard to clean them.

If the battery heats unevenly, then it is dirty.

The primary source of problems in heating systems is hot water, the main coolant.

1. Firstly, hot water, interacting with the materials from which the system is made, can provoke chemical reaction. Consequences - scale.
2. Secondly, the properties of water themselves. It can contain a great many different impurities, which can provoke not only banal corrosion, but also contribute to precipitation and plaque on pipes.

It is the occurrence of deposits from all of the above that can lead to the quality of the operation of the heat elements of the system.

An interesting fact is that even a layer of deposits is only seven to nine millimeters, the efficiency of the heating system drops by more than 42%.

And, of course, all this affects the life of the heating elements in general, they quickly become unusable.

Types of flushing heating systems

Chemical flushing of heating

This method is based on the dissolution of various substances deposited on pipes in chemical compounds. This is one of the most effective, used and proven ways to clean the heating system from excess.

Chemicals liquefy all components of deposits, scale, which are then naturally washed out of the heating system. As a rule, the composition of such substances includes an element that protects pipes from the appearance of signs of rust, and extends the period of operation.

In order to clean the pipes in this way, you must have special equipment.

Usually, specialists use pumps in such cases. It is needed so that after injecting a chemical solution into heating devices, the pump gives direction to its movement through the system. The time spent on cleaning depends on each material in the heating system, the strength of the dirt and the selected substance. In addition, the process of enveloping pipes from the inside with an oxide film also has its own time frame.

This method has several significant advantages:

• Firstly, this is the cheapest and most proven method of cleaning the heating system;
• Secondly, the speed of manifestation of results, it is very high;
• Thirdly, flushing can be carried out without stopping the heating, which allows it to be used at different times of the year.

The disadvantages of the method are that, first and foremost, it cannot be used for flushing aluminum pipes(since this can destroy their integrity), second, like any chemical, the solution is toxic.

Sequence of actions when using this method flushing the heating system

1. First, try, in as much detail as possible, to consider the existing heating system in order to choose the right chemical solution
2. Pay attention to the instructions for the composition. Means can have a different consistency and it is necessary to dilute the chemical as it is written in the recommendations for it.
3. Connect the pump to the system, having previously filled the tank intended for this with the composition.
4. Make sure that chemical agent circulates in the system. We repeat that the time depends on the strength and composition of the pollution.
5. Remove the chemical from the system, flush it with water and refill.

Dispersed flushing heating

Let's call this method the "second" generation of chemical. Its action is as follows: chemical composition does not react with metal and only affects the polluting composition (silt, dirt, scale) and its interaction with the heating system. A pump is also needed.

The advantages of this method can be called:

1. Firstly, this method is suitable for any heating system, no matter what material it is made of, and for any time of the year.
2. Secondly, the reagents are non-toxic.
3. Thirdly, as in the case of the first method, all pollutants are already removed at the stage of decomposition and cannot re-form the blockage. And, of course, in the future, our heating system will be protected during further operation.

Instruction:

1. Determine required amount solution selected specifically for your heating system.
2. Connect the pump to the system by filling the appropriate container with the reagent.
3. After cleaning, flush the system, dispose of the composition.
4. If you are cleaning heating period, then it is necessary to connect a device that will close the heating system.

This method is based on descaling by supplying water under high pressure through certain nozzles. This is an environmentally friendly method, which, by the way, copes well with pollution on cast iron. Due to the properties of this metal, chemical method may not be very efficient. However, it is relatively more expensive (since you need special equipment capable of delivering a jet of water under pressure of several hundred atmospheres) and high-quality cleaning will not come out without the help of third parties. The fact is that before you start cleaning, you need to treat the dirt with a solution that can soften them.

Pneumopulse method of flushing the heating system

This method is based on generating small explosions. air bubbles, which are able to tear off pollution from the inside. For this, the following are used: an air gun, a switch, equipment for supplying air with an accumulation system (for example, a compressor), adapter (connecting) hoses.

How does the installation work?

First, the air gun is connected to heating pipes through the hose and switch, then comes the compressed air transmitter. Further, a liquid is passed through this entire system, which sets the piston in motion and, in fact, starts the installation.

If you decide to use a compressor to supply air, then when water is introduced and the piston position changes under its pressure, the empty container begins to fill with air. After the cylinder is full, part of the air will move into the piston, which, directing it into the heating system, will create a shock wave.

In order to completely clean the system, you need from two to five strokes. The process itself will take several minutes, and is completely independent of electricity - the installation works autonomously.

Of the minuses this method you can call it a limited range, due to the characteristics of the gun.

The easiest way to implement, and which will not require any investment other than labor.

This is the usual mechanical cleaning, which is possible in any apartment, house.

Instruction:

1. First of all, it is necessary to disconnect the radiator from the system and drain all the liquid from it. Be sure to cover all surfaces with unnecessary rags so as not to spoil or damage the coating. If you have a special tap on the batteries, this will greatly facilitate the task. In the event that the house is cast iron batteries, it may be necessary to remove them a heating element(to make it easier to unwind the connection).
2. Next, the radiator must be flushed. The easiest way to do this is in the bathroom, directing water from the shower hose at maximum pressure into the pipes. You need to do this for as long as it will run rusty water. If there is too large and noticeable layer of deposits inside the pipes, use a metal fixture. As soon as the pollution stops washing out of the battery, the cleaning is completed.
3. We wash the pipes in the same way, cleaning individual segments.
4. Be sure to clean the threads from corrosion before assembling the system.

Buying Tips

• Please note that aluminum bimetal radiators, convectors have a relatively small volume, in which the circulation rate of the coolant does not allow sediment to be released.
• choose closed systems. Since in such systems the volume of water does not change, the volume of pollution that appears new remains the same.
• Connect batteries from below. As already mentioned, deposits accumulate on horizontal lines, which means that the bulk will leave with the flow of the coolant.
• Install a dirt filter. This is a relatively cheap fixture that will make cleaning easier for you. It is much easier to remove scale from one part than to clean the entire riser.

Video - how to clean a heating radiator with your own hands

Flushing of the system is necessary after repair, installation, as well as after completion of heating season to remove sludge and dirt.
The most effective is the hydropneumatic flushing method - bubbling water from compressed air to create a rapid movement of the environment in the system.
To exclude the possibility of contamination of an already washed area, washing is carried out in this sequence.
For flushing heating systems, the following fittings must be cut into the inlet (see Appendix 1):
for connecting the compressed air pipeline from the compressor DN 32mm (18),
for pipeline connection cold water DN 50mm (19),
for drainage of drained water DN 50mm (20).
To ensure the possibility of removing large contaminants from pipes, the diameter of the drain pipes should be taken from the following ratios:

Pipe length, mm up to 70 80-125 150-175
D branch pipe, mm 25 40 50

Discharge of flushing water if present drainage device in the chamber it is carried out directly into the drainage, and in the absence of drainage into the nearest storm drain or into the chamber, from where it is pumped out by pumps.
When flushing heating networks, mobile compressor stations such as VKS-1, AK-B, DK-9, with a capacity of 5-6 m3 / min, pressure up to 6 atm, or another type of diesel compressor can be used.
Depending on the bandwidth drainage device, compressor power and possible expense water, several flushing modes are used.
The normal flushing regime is considered to be the movement of the mixture, accompanied by shocks, slips alternately of water and air.
When inlet compressed air into the washed area, it is necessary to ensure that water cannot enter the compressor receiver, for which the valve on the water supply system should open only after the pressure in the receiver becomes greater than the water supply pressure.
Assuming the reduced rate of movement of the flushing water equal to 1 m/s, the approximate water consumption during flushing for various pipe diameters will be:

Pipe diameter, mm 50 70 80 100 125 150 200
Water consumption, m3/h 8 14 20 30 50 65 125

pressure tap water is selected in the range from 1.5-3.0 atm. With a pressure of more than 3.5 atm, stressful operating conditions of the compressor are created, under which it cannot provide a normal flushing of the network.
At a pressure of 1 atm, compressed air from the compressor can close the access of water to the pipeline and at the end of the section, one air will exit. In this case, you should alternate the operation of the compressor with its stops for 10-15 minutes with a continuous supply of water.
Keep the air pressure in the flushed pipeline at 3-3.5 atm.

In addition, it is necessary to comply with the requirements for the placement and placement of input nodes in accordance with SNIP ||-33-75, and each input node must contain (see Fig. 1.):
- water jet elevator (16),
- installed calculated narrowing device (nozzle) (17),
- mud collectors on the supply and return lines (14.15)
- four valves (1,2,3,4)
- inserts for pressure gauges (5,6,7,8,9)
- inserts for thermometers (10,11,12,13).

If there are no tie-ins for flushing the internal heating system and, as a result, no flushing is carried out, the consumer will not be connected during the heating season, as it clogs the heat distribution networks.
And also the absence of tie-ins for pressure gauges and thermometers does not make it possible to carry out commissioning work, consequently, consumer claims for unsatisfactory heat supply will not be accepted and all responsibility lies with the Housing Office.

Heavily polluted heating systems, long time not subjected to washing, washed in three stages.
First stage.
Flushing with compressed air of each riser from the bottom up with the heating system filled with water (to loosen deposits), starting from the most distant riser.
Second phase.
Flushing each riser with an air-water mixture.
Third stage.
Flushing of distributing pipelines with water-air mixture.

With annual flushing, you can limit yourself to flushing risers in groups (up to 5 risers).

The procedure for flushing internal heating systems
hydropneumatic method.

1. ZhEK agrees with the regional branch of the enterprise the schedule for flushing.
2. By the specified time, a representative of the enterprise (master of the thermal district) is invited and, in his presence, the housing office starts flushing work.
3. For the period of flushing, the heating system is disconnected from the quarterly network with valves 1, 2, 3, 4, and if they are not dense enough, additional plugs (blinds) are installed from sheet steel with a thickness of at least 3 mm.
By the beginning of the heating season, all four valves must be inspected.
4. Attach flexible hoses (rubber hoses) to the flushing fittings using half nuts according to GOST 2217-76 (half nuts "ROT"). It is mandatory to provide for cold water and air inlets check valves.
5. Flushing is carried out after the nozzle is removed from the elevator.

The system is filled with water through the valve 19 with the valve 21 of the air collector open and the valves (valves) 22.24 open and the valves (valves) 1,2,3,4,18,20,23 closed. After the appearance of water in the tap 21, the tap and valve 19 are closed.
Produce air purge of each riser.
To do this, close all the taps 24 on the risers. Open valve 18 (air). By successively opening the valve 22 on the risers, the risers are blown with air from the bottom up.
To drain water into the sewer, fitting 20 is put on a flexible rubber hose to throw the mixture into the storm drain.
Rinse each riser, starting with the most remote.
To do this, the valve 22.24 is opened sequentially on the risers with the air vent 21 open. The valves 19 (water) and 18 (air) are opened.
Then for flushing:
sequentially fill the risers with water;
close the taps 21, 23;
open the water drainage through the valve 20.
Turn on the air through the valve 18 and with the valves 19, 20 open, the risers are turned on in series by opening the valves 24 (gates), starting from the most remote riser.
In systems with lower wiring heating circuits, flushing is similar. The system is filled with water through the valves 19, 24 (valve), 22 with the tap 21 open.
Then each riser is purged with air, starting with the last one. With constant flushing, discharge from the riser can be done through valve 23a.
To drain the water-air mixture from several risers, the mixture is discharged through drainage 20 into the storm drain (see Fig. 2).
The calculation nozzle is installed.
Filling the system network water, is carried out in the presence of a representative of the enterprise.

How is the heating system flushed?

Before and after washing

In order for the water heating system to work perfectly, it is necessary not only to operate it correctly, but to periodically carry out preventive examination and repair, which includes maintenance and flushing of the heating system. Specialists are constantly faced with these processes, it was for them that the procedure for carrying out and the list of works that are used in the prevention of the system were developed.

For many, it may seem that this instruction should only apply to systems central heating. This document is valid for all types of systems without determining the power, size and number of equipment and devices. Therefore, it makes sense to familiarize yourself with the basic rules of how to flush.

The procedure for carrying out work on flushing heating

Firstly, there is a need to inspect the entire system and its individual parts. To do this, the butt joints of pipes, pipes with radiators, pipes with a boiler and a boiler, as well as pipes and instrumentation and automation are visually viewed. Joints are checked for water leakage. If any are found, then they must be repaired or replaced with new ones.

Secondly, before the start of the heating season, a test run of the system is carried out, during which the air accumulated inside the pipes and appliances is removed from it. For this, special air valves are used. Currently, experts recommend the installation of automatic air valves, which independently release air without human intervention until water flows out of the valve, after which the valve closes.

Thirdly, if a circulation pump is installed in the system, then it must be inspected, lubricated and turned on for testing.

Now you can start the process of flushing the heating. This is a serious operation, where you will have to accurately use the staging of the implementation.

1. The water supply valve is closed, the electricity is turned off.
2. Through the drain valve, which is installed on the boiler, water is drained into the sewer.
3. To speed up the draining process, it is necessary to open the air valves on the heating radiators. Not all, but only those who are located above the rest. For example, on the second floor of the house.
4. The water supply valve is opened, flushing is carried out until the water coming out of the drain valve is clear.
5. Filling the system that starts with the boiler. For better operation of the heating system, it is necessary to add corrosion inhibitors to the water. To do this, the uppermost air valve is opened, through which inhibitors are added.
6. Completeness of filling must be controlled by the level of water inside the safety tank. She should fill the tank only halfway. During operation, the water will heat up and expand in volume, which will lead to its pouring out of the system. Half the volume of the tank will be sufficient to prevent this trouble from occurring.

As you can see, the technology is quite simple, and you can safely do it yourself. But this is the easiest way that does not require the presence special equipment so it's not the most efficient.

Types of flushing

Apparatus for flushing heating

There are two types of system flush:

The first is applied only if all elements of the system are contaminated with silt deposits. The second is used if scale or corrosion build-up has formed. But, as practice shows, chemical cleaning heating systems are more in demand today than the first option. The whole point is that in autonomous systems most often used tap water, which does not shine with quality. Hence the scale, and corrosion of metals, and silt deposits, which can only be handled by chemical reagents.

Using any type of flushing, it is necessary to use special equipment, usually compressors. The movement of water during flushing must correspond to the circulation of the coolant inside the system. This is very important point. But sometimes, this applies only to the pneumohydraulic method, it becomes necessary to counterflow water during washing. What for? In places where pipelines branch off, pockets are formed from the swirling of the liquid, where silt deposits accumulate. And they often cannot be removed by direct flow. That's why you have to install the compressor in the opposite direction.

If the house is large, then you need to flush each circuit separately. And be sure to follow the flushing scheme, which has its own sequence:

1. Flushing radiators.
2. Pipes supplying heated water to radiators.
3. Pipes that drain cooled water.

How to flush radiators?

This process is not complicated, but requires certain information. The easiest is to rinse the batteries with water with the addition of caustic or soda ash. Both of them are on sale today. To do this, disconnect the batteries from the pipes of the heating system and remove them from the brackets.

After that, be sure to plug one hole from the pipe, and pour water mixed with soda into the second. Fill up to the brim. After that, the hole is also muffled. In this state, the radiator is left for an hour and a half, then you need to shake it, moving from side to side, you can knock on its sections with a mallet. Then the water is drained into a container, it will still come in handy for the next radiator. And finishing touch- it's a wash clean water, you can use a compressor, this is the best option.

Flushing radiators can also be done with a special liquid that is used to clean car radiators. But in this case, this liquid can be filled in only for ten to fifteen minutes, after which the battery is well washed with clean water. By the way, the liquid must be diluted only with hot water.

Modern chemical cleaning companies also offer radiator flushing products. Not many of them can boast of excellent cleaning properties, but there are decent specimens.

Conclusion

Cleaned from silt, scale and corrosion, the elements of the heating system are subjected to less stress. The passage of water is greatly facilitated, the heat transfer of the radiators increases, the pump runs without load. This leads to big savings fuel and in the form of electricity for the pump, and in the form of fuel for heating the coolant. And this is a clear savings. Money. So two tips:

1. Flush as often as possible.
2. Use purified and filtered water in the heating system. In this case, flushing the system can be carried out not once a year, but once every several years.

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The operation of heating systems in residential buildings should ensure:

Maintaining the calculated (required by the standards) air temperature in heated rooms according to SNiP 2.08.01 - 89 * (Table 6.1);

tightness of the system;

Noise level in the aisles acceptable standards(30-35 dB).

Maintaining the design air temperature in heated rooms is ensured by regulating the parameters of the coolant: the temperature and pressure of the coolant at the inlet and outlet of the heating system, depending on outdoor temperature air, hydraulic characteristics of the heating system and heating network.

The maximum operating pressure in the heating system must not exceed: when installing cast iron radiators- 0.6 MPa (6 kgf / sq. cm), with steel heaters - 1 MPa (10 kgf / sq. cm). The heating system must be airtight over the entire pressure range.

There are the following levels of regulation:

Central - in the source of heat supply;

Group - in the central heating station (for a group of buildings);

General house - ITP (for the entire building or facade);

Individual - on heating devices in the room.

AT modern systems heating are widely used various schemes automation of their work (for example, automation of heating systems with an elevator with an adjustable nozzle section; the same with a pump on the return pipeline; the same with a pump on the jumper). Design standards require the installation of regulation, control and accounting devices for heat consumption for each apartment, and heating devices to install control valves (usually automatic temperature controllers).

To the main tasks Maintenance and repair of heating systems also include saving heat and ensuring the good condition of the elements of the system.

Maintenance of the heating system includes monitoring its operation and troubleshooting. At the beginning of the heating season, a system bypass schedule is drawn up, which includes following works:

Detailed inspection of distributing pipelines - at least once a month;

Detailed inspection of the most critical elements of the system (pumps, main shut-off valves, instrumentation, automatic devices) - at least once a week;

Removal of air and heating systems through the air collector or air outlet valves on heaters when the pressure on the supply pipe drops below the level static pressure this system, as well as after its adjustment;

Control over the temperature and pressure of the coolant;

Replenishment of lubrication of pump bearings;

Flushing of mud collectors, the need for which is determined by the pressure drop on the pressure gauges before and after the mud collectors;

Inspection of in-house devices and devices in technical underground, lofts, stairwells- twice during the heating period; during this inspection, the tenants of residential premises are explained the rules for energy saving and the facts of unauthorized conversion of elements of heating systems are established;

Restoration of damaged thermal insulation of pipelines and fittings located in unheated premises;

Checking the operability of gate valves and valves (their control devices are closed to failure, followed by opening to the previous position) - twice a month;

Inspection technical condition heating point equipped with means automatic regulation, and checking the maintenance of the specified parameters of the coolant - at least once a day, etc.

During inspections, immediately eliminate all visible water leaks, repair or replace faulty shut-off or control valves. The shutdown time of the entire system or its individual sections when eliminating water leaks or other malfunctions is set depending on the outdoor temperature for up to 2 hours at the estimated outdoor air temperature. At a negative outside temperature, if the circulation of water in the heating system has stopped and the water temperature has dropped to + 5 degrees C, it is necessary to empty the heating system.

Malfunctions that do not significantly affect the operation of the heating and cannot be eliminated immediately are noted in defective statements, are included in the current or major repairs plan and are eliminated in the summer in preparation for the next heating season.

The plan for the maintenance and overhaul of the heating system includes the actual repair and replacement individual elements systems with inspection of shut-off and control valves, as well as flushing, hydraulic tests, trial run and commissioning. The schedules for these works are agreed with the heat supply organization conducting similar works on thermal networks and sources of heat supply.

During repairs, worn-out heating devices, pipelines, shut-off and control valves, air outlets and other equipment, thermal insulation are replaced in accordance with the project or recommendations of the commissioning organization.

In the process of repairing the system, the fastenings of all equipment are checked and restored, the required equipment slopes are provided, pumps are cleaned and repaired, instrumentation is removed and handed over for inspection.

Removal of gate valves for internal inspection and repair (scraping of discs, checking the density of rings, pressure testing) is carried out at least once every three years; checking the tightness of the closure and changing the stuffing box seals of the control valves on the heating devices - at least once a year; replacement of sealing gaskets of flange connections - at least once every five years. Setup, cleaning and repair automatic regulators carried out according to the manufacturer's instructions.

After the completion of the repair, as well as the heating season for removal from inner surface pipelines of various deposits, dirt and scale from the system, it is flushed by hydraulic or hydropneumatic methods. Hydraulic flushing provides for the creation of a speed of tap water 3-5 times higher than the operational one. To do this, a fitting is installed at the lowest point of the system (washed area), through which water is discharged into the sewer through a hose. In some cases, network or circulation pumps. The use of water with compressed air ( hydropneumatic flushing) more efficiently, because due to the high turbulence, the movements are better loosened and carried out of the sediment system. A chemical flushing method is also used, which consists in attaching a special installation to the system, which has a container for a chemical solution capable of dissolving scale-corrosive deposits on the inner surface of pipelines and heating appliances when circulating through a closed office.

With annual hydropneumatic flushing, they are limited to flushing a group of two to five risers. After acceptance new system in service or after overhaul flushing is carried out in several stages: each riser is blown with compressed air from the bottom up, each riser and distributing pipelines are flushed. Flushing is carried out until the removed water-air mixture is completely clarified, after which the system must be filled with network water (or water from the boiler room). Do not keep the heating system empty.

Hydraulic tests are carried out after flushing the heating system. With their help, check the tightness of pipelines and connections. Before hydraulic tests, the tested heating point and the heating system are separated from the heating network with steel plugs at least 3 mm thick, installed after the inlet valves. Check the opening of all shut-off and control valves in the circuit of the system under test, including taps for heating appliances. The system is filled with water from the city water supply through the return pipeline of the heating point with open air valves, which are closed after the appearance of water in them. Heating systems with steel radiators(panel heaters, stamped steel radiators) should only be filled with heating water. If the pressure in the water supply is lower than the static pressure in the system, then the systems are filled with a pump. Then, a test pressure test of the system is carried out with a working pressure and the observed shortcomings are eliminated.

Hydraulic tests are carried out at a pressure equal to 1.25 of the operating pressure of the coolant. Basically, the pressure in the system is created due to the actual water pressure in the city water supply. In some cases, the pressure is provided by a hydraulic press. The heating system is considered to have passed the test if no visible water leakage is detected and the pressure drop on the control pressure gauge after five minutes does not exceed 0.02 MPa. Before the heating system is put into operation, it is emptied from tap water, which was pressure tested, and filled with purified water from the heating network.

A trial run of the heating system is carried out after its pressure testing and flushing, bringing the temperature of the coolant to 80-85 degrees C, while air is removed from the system and the heating of all heating devices is checked.

Adjustment of the heating system includes checking and adjusting the distribution of water along the risers and floors, in which temperature differences in the risers and temperatures on the inlets and in the middle part of the devices in the premises are measured: when working in apartments, they also determine the air temperatures in the rooms and in the stairwells, relative humidity air in living rooms.

Adjustment is made using valves or taps installed on the risers and connections to the devices. In some cases, adjustment can only be made using throttle diaphragms.

Measures to eliminate noise penetrating into living quarters from operating equipment consist in regular replacement (once every three years) of soft inserts and vibration-isolating nose pads.

When performing maintenance and repair work on residential heating systems, it is recommended to keep the following documentation:

Logbook for registering the operation of the heating system, in which the readings of control and measuring instruments installed in heating point;

Passport of the heating system, which contains specifications systems, layouts of the main units and risers;

Instructions for starting, adjusting and emptying the heating system;

It turns out the order of maintenance of the system, temperature regime in heated rooms, methods and methods for regulating heat transfer, means and procedure for communication with the dispatcher heat supply organization and emergency services;

Troubleshooting log.

To save the consumption of thermal energy, fuel and water, it is necessary to use means of automatic regulation and control over the operation of the heating system, maintain the design parameters of the temperature and pressure of the coolant in it, reduce heat loss in residential buildings through enclosing structures, to maintain thermal insulation pipelines are in good condition.

In order for the house to be warm all the time, it is necessary to strictly observe rules for flushing heating systems, which consist in descaling and lime deposits. According to the rules, for each type of deposits there are various ways washings, which are recommended to be used. Scale in the heating system is formed due to the presence in the water a large number sodium, calcium and magnesium, as well as other substances.

As a rule, and water heating devices are carried out at least once a year. In principle, it is possible to do it twice for preventive purposes, but it is advisable to use a special flushing solution, the concentration of which depends on the type of scale and the degree of contamination of the system. Today, there are already ready-made flushing liquids, but you can prepare them yourself using sulfuric, hydrochloric or phosphoric acids. But if there is no experience in preparing such solutions, then it is better not to do this, but to invite employees of specialized companies who know all the rules and requirements for washing. The fact is that the acids that make up the flushing fluid are very aggressive, and affect not only deposits, but also the walls of pipes and radiators of the heating system and elements of water heating devices. There are many cases when, after unskilled washing, the sealing elements of water-heating boilers and radiators became unusable, which entailed expensive repairs.

But for safety reasons, it is better to flush hydropneumatically. There are strictly defined and its subsequent crimping, which must be strictly observed. Flushing should be carried out before the start of the heating season and after it using special equipment. As soon as the heating season ends, all heating equipment subject to flushing and subsequent pressure testing as required building codes and rules. According to the same rules, system tests should be carried out according to a certain scheme, while observing safety precautions.

Before the start of the heating season, it is carried out in a hydropneumatic way, while household and drinking water can be used. For these purposes, a special blowing compressor is used, which supplies air under pressure to the water supply and heating system. It is better to dismantle the nozzles and diaphragms of the hydraulic elevators during flushing. The water pressure in the pipelines during the flushing process should not exceed the working pressure, and the air pressure, according to the rules, should not exceed 0.6 MPa. As for the speed of water, it should not be too high, it is permissible to exceed it by 0.5 m / s of the speed of the coolant.

According to the rules, hydropneumatic washing is carried out until the outlet becomes completely light. At the end of the process, the heating system must be immediately filled with coolant, because it is strictly forbidden to keep it empty. After flushing, it is necessary to carry out hydraulic tests, and this must be done at least once a year and separately for the heating system and heat points. The pressure should be within 1.25 of the working one.

Testing of heating systems should be carried out in accordance with the following rules:

1. The pressure must be maintained in top point pipelines. Liquid temperature - no more than 45 degrees, air is removed through special devices located at the highest point.
2. The pressure must be brought to the working one, after which the places of flanged and welded joints, partings and equipment should be inspected. The time required for verification is at least 10 minutes.
3. If after ten minutes no defects have been detected, the pressure can be increased to a test pressure. Such pressure must be maintained for fifteen minutes, and then lowered to working pressure. A reference manometer is used to monitor and determine the pressure.

If you follow rules for flushing the heating system, then at the end of it the system will function as new.