What to do if there is poor water pressure in the tap? The hot liquid slowly cooled.

Part 1

A1. The figure shows a graph of the projection of body velocity versus time.

The projection of body acceleration in the time interval from 12 to 16 s is presented by the graph:

A2. Strip magnet with mass m brought to a massive steel plate weighing M. Compare the force of a magnet on a plate F 1 with the force of the plate on the magnet F 2 .

1) F 1 = F 2 ; 2) F 1 > F 2 ; 3) F 1 < F 2 ; 4) F 1 / F 2 = m/M.

A3. When moving on a horizontal surface, a sliding friction force of 10 N acts on a body weighing 40 kg. What will the sliding friction force be after reducing the body's mass by 5 times, if the friction coefficient does not change?

1) 1 N; 2) 2 N; 3) 4 N; 4) 8 N.

A4. A car and a truck are moving at speeds υ 1 = 108 km/h and υ 2 = 54 km/h. Car weight m= 1000 kg. What is the mass of the truck if the ratio of the truck's momentum to the car's momentum is 1.5?

1) 3000 kg; 2) 4500 kg; 3) 1500 kg; 4) 1000 kg.

A5. Mass sled m pulled uphill at a constant speed. When the sled rises to the top h from the initial position, their total mechanical energy:

1) will not change;

2) will increase by mgh;

3) will be unknown, because the slope of the slide is not set;

4) will be unknown, because friction coefficient is not specified.

1) 1; 2) 2; 3) 1/4; 4) 4.

From the FIPI website http://www.fipi.ru. Instructions for completing the Unified State Exam-2009 work, criteria for evaluating solutions to problems in Part 3 for 1 and 2 points, conditions for recording solutions to tasks, as well as another option, see No. 3/09. – Ed.

Water / Cold and hot water meters

The situation is familiar to almost everyone: in the morning a barely warm liquid runs from the hot water tap, which you have to use to wash your face. If you have time, you can open the tap and drain cool “hot” water for 15-20 minutes until it reaches the desired temperature.

However, if the apartment has a hot water meter, cubic meters of lukewarm water poured down the drain will cost the owner of the living space the full cost of heated water, which is 4-6 times more expensive than cold water.

It often happens that “hot” water is not too different in temperature from “cold”. And instead of mixing hot and cold, you leave only the hot tap open. Lukewarm water flows from the faucet. And it stands like hot water.

What to do in such a situation? Resign yourself and overpay? And if we fight, then how exactly? Let's figure it out together.

Cold water from a hot tap: legislation

First, let's find out what the current legislation says about the requirements for the temperature of hot water supplied to an apartment building.

Requirements for the quality of hot water supply are specified in two documents:

• “Rules for the provision of utility services to owners and users of premises in apartment buildings and residential buildings”, approved by Decree of the Government of the Russian Federation of May 6, 2011 N 354 Or rather, in its Appendix No. 1, which is called “Requirements for the quality of utility services”
• Sanitary and epidemiological rules and regulations SanPiN 2.1.4.2496-09 “Hygienic requirements for ensuring the safety of hot water supply systems”, approved by Resolution of the Chief State Sanitary Doctor of the Russian Federation dated April 7, 2009 N 20 “On approval of SanPiN 2.1.4.2496-09”

The following follows from these documents:

• The temperature of hot water in water supply points, regardless of the heating system used in an apartment building, must be no lower than 60°C and no higher than 75°C
• Before determining the hot water temperature, the water is drained for no more than 3 minutes.

Permissible deviation of hot water temperature:

• at night (from 0.00 to 5.00 hours) - no more than 5°C;
• in the daytime (from 5.00 to 00.00 hours) - no more than 3°C

The requirements for the quality of hot water supply also imply the terms of payment for this utility resource if the water is not at the right temperature.

Firstly, the hours in which the supply of hot water with a temperature of less than 40°C is recorded are summed up. And during this period of time, payment for consumed water is made at the cold water supply tariff.

Secondly, if the temperature is below the legally established 60°C, but above 40°C, then the charge for hot water is reduced.

The mechanism is as follows: for every 3°C deviation from the permissible deviations in hot water temperature, the amount of payment for water in the month in which the specified deviation occurred is reduced by 0.1% for each hour when such a decrease was recorded.

Why (physically) hot water turns out to be lukewarm?

Having understood the legal requirements for permissible hot water temperatures, we will consider the reasons why these requirements may not be met in your home.

First of all, these may be problems directly in your home. For example, design flaws in the hot water supply system (there is no circulation of hot water and in order for residents of the upper floors to get hot water in the morning, they need to drain the water that was in the risers all night and had time to cool down).

Or incorrect adjustments of the hot water supply system. Simply put, for some reason the building management organization does not sufficiently heat the water that goes to the apartments.

Alternatively, the circulation of hot water may deteriorate due to a clogged pipe on the floor below (for example, they cut in a “goose” to hide the hot water pipe in the wall of the bathroom and thus free up space for the bathroom).

Or - due to improper installation of an electric boiler (bidet, mixers, etc.) in one of the apartments along your riser.
In all these cases, solving the problem at one cost or another, but it is possible with the help of pressure on the management organization of your home.

More serious in its consequences is the option when hot water does not have the required temperature for external reasons not related to your home. For example, when your house is the end of the hot water supply line. Those. First, several high-rise buildings up to you take hot water. And only then the water pipeline goes to your house. And if this line is not looped, then it turns out that in your dead-end branch the hot water cools down by the morning (and sometimes it does not warm up to the required temperature at all).

And in this case, the organization responsible for managing your home, with all its desire, will not be able to ensure that problems with hot water are eliminated. Work on relaying hot water supply lines (a) is too expensive, (b) is carried out in an area where your management company cannot manage.

Exactly the same can be said if hot water is not supplied to the house due to an accident (destruction of the water supply) outside the home networks. The management organization cannot eliminate violations. This is a matter for the heat supply organization and municipal authorities. As practice shows, it is much more difficult to “put pressure” on them.

What to do if the hot water is lukewarm?

So, what should you do if lukewarm water flows from your hot tap? First of all, you need to inform your management organization about this, call its representative to the apartment so that he can take water measurements and draw up a corresponding report in your presence.

If measurements show a temperature below the established standard, then starting from the day the act is drawn up, the requirements of the law to reduce water charges come into force (which we discussed in the chapter on legislation). If, for example, it is determined that your water temperature is below 40°C, then you will pay for the cubic meters calculated by the hot water meter at the same rate as for cold water. This will continue until the next report is drawn up - on eliminating violations of the requirements for hot water temperature.

What to do if you called the control room by phone and didn’t even write a statement, but there was no response, you ask? Or was the act drawn up, but the water remained cold?

In this case, you need to contact the housing inspectorate of your region (locality). Inspections usually respond to such requests and they have effective leverage over the management organizations of apartment buildings. To begin with, an order may be issued, then a decision on a fine, transfer of the case to court, revocation of the license, etc.

In addition to the housing inspection, it is also possible to contact the prosecutor's office and directly to the court with a statement of claim. Courts consider such cases and make decisions in favor of citizens. In addition to the obligation to provide the apartment with hot water at the required temperature, utility workers are also forced to pay compensation for moral and material damage.

If you want to delve into the details of the process, you can look, for example, at this decision of the Kirovsky District Court of the city of Perm in a case involving cold water from a hot tap.

But here, of course, you need to understand that when the matter reaches the level of litigation in court, there will not be a quick solution to the problem. And the result is not guaranteed. Even if the court decides in your favor.

As mentioned above, the solution to the problem with hot water may often depend not on the management organization, but on the owner of the heating networks and hot water supply networks. Infrastructure reconstruction may also require participation and funding from municipal authorities. In general, the process will be long, nervous, and most importantly, you will be without hot water all this time.

Water heater as a way to solve the problem with cold hot water

So it turns out that perhaps the most effective way to “fight” would be to switch to an autonomous hot water supply. In other words, install an electric water heater (boiler). Let's consider this issue from a practical point of view.
The heater can be flow-through or storage. It is better, as experience shows, to use a cumulative one. This is a container with a volume of up to 200 liters with a heating element (which heats the water) inside and a layer of thermal insulation material (which prevents the water from cooling) on ​​the outside.

The unit looks quite aesthetically pleasing. Thanks to the thermal insulation layer, which prevents the water from cooling, it does not consume much electricity.

As calculations show, if the consumption of hot water is not too active, heating water in a boiler turns out to be comparable in price to centralized hot water supply. But, of course, you won’t be able to pour hot water from the heart - the water heater’s capacity is limited, and if you have drained all the water (for example, the children took turns splashing to their hearts’ content in the bathroom), you have to wait until it warms up again.

An important reminder - if you do not have a hot water meter in your apartment, then when installing a boiler, put an official plug (seal the tap) at the entrance from the hot riser. Otherwise, you will continue to be charged for hot water based on current regulations.

If you have a hot water meter, then when installing a water heater, there is no need to plug the hot water riser. Simply close the inlet valve. Also, make sure that hot water from your boiler is not mixed into the home water supply system.

Hot water meter with temperature sensor

Finally, it is worth mentioning another way to save money on the family budget - a hot water meter with a temperature sensor.

This device takes into account separately the flow of really hot water (whose temperature corresponds to the standard) and actually cold water (that which comes from the hot water supply riser, but in reality is slightly warm).

The principle of operation of such devices is based on the differentiation of consumed volumes of water: the volumes of hot water and the water that comes from a hot tap, but its temperature is below normal, are taken into account separately. You add the cubic meters that the meter counted in the second case to the volume of cold water consumption and pay at the appropriate rate.

An example is the Sayany T-RMD hot water meter; this is the most common device of this kind. Although there are others that are similar.

At first glance, everything looks nice - without contacting utility companies, you only pay for the “hot water” that meets the standards. However, as is usually the case, there are several “buts”.

Firstly, the recalculation of payments for hot water that does not meet the requirements of the law must occur in accordance with the requirements of this very legislation. That is, according to the procedure, with calls from a representative, “acts”, etc. The legislation does not mention automatic recalculation of readings based on the readings of the “thermal sensor”. This is the position of the utility companies and there are several court decisions that support it.

Secondly, it is worth remembering that it is not enough to install the meter; it must also be sealed and “put into operation.” This cannot be done without utility workers (employees of the management organization). Whether they will accept the meter or not is an open question. In some places they are loyal, in others they are not.

Thirdly, considering the consumption of water from a hot riser as cold, you thus shift the payment for this volume to general house needs. That is, for all residents of the house.

Fourthly, and this is the main thing! - a meter with a temperature sensor does not provide you with hot water. And this brings us back to the problem of installing a water heater.

Problem with cold water from a hot tap. Summary

So, a quick summary. Cold water from a hot tap can be a problem. And if we are talking about problems within the house system, then it is quite possible to win. Especially if the problem is related to the system settings or its not very complex reconstruction.

If the quality of the hot water supply is low due to problems outside the home system, then you may not be able to resolve the issue. In this case, you will have to install a water heater; there seems to be no other way out.

When water flows poorly from a faucet, you can only deal with the problem by knowing what caused the poor pressure. Weak pressure prevents you from fully using the shower or bath. Problems with water significantly reduce the comfort of living, making it impossible to fully enjoy the benefits of civilization.

Reasons affecting water pressure in the tap

To eliminate a malfunction that leads to a loss of pressure or its complete absence, you need to understand why the water from the tap is not flowing well.

Most often the problem lies in the following circumstances:

1. Faucet clogged. A decrease in pressure and a decrease in water flow occurs due to clogging of the aerator, which is an insert and filters water. Confirmation of this theory of breakdown is such a violation as a decrease in pressure in only one mixer, when other taps in the house are working normally.
2. Formation of a plug of rust, silt particles and scale in the pipe. A gradual decrease in pressure in this situation can lead to complete blocking of the throughput diameter of the connecting filter or the pipeline fittings themselves.
3. Reduced water supply pressure in the water main. The problem may be at the pumping station level. Depressurization of the pipeline is also possible.
4. Incorrect calculations when designing a water main. For example, during installation, pipes of a larger diameter were used than those used on neighboring branches; large length of water pipes, which does not correspond to the capabilities of pressure equipment.

A drop in pressure of both hot and cold water can be caused by factors such as the simultaneous consumption of liquid in large quantities. As a rule, under such circumstances, water does not flow well in the evening, when the bulk of the area's residents return home.

Solving pressure problems

If the pressure drops or the water does not flow at all, you can try to find out the cause of the problem yourself and then fix it. It is worth noting that not all breakdowns can be repaired yourself. In case of accidents at the station, depressurization of the pipeline and similar reasons, repairs are carried out by the relevant competent services.

You can try to clean the clogged section of the pipe from the riser to the valve with a special cable. When water does not flow well from the neighbors below and above, it can be said that the riser is clogged. It is almost impossible to clean it. It must be replaced.

All repair work is carried out after the water is turned off.

If the tap itself is clogged, the mixer can be cleaned. To do this you will need an adjustable wrench. Use it to unscrew the aerator. Due to the fact that the aerator has small nozzles, it clogs quickly. To clean the aerator, you need to place it under running water and rinse it. When the problem is not in the aerator, you will need to dismantle the valve and unscrew the lock washer that holds the locking element in the housing seat, and get to the axle box and remove it. Next, the body is cleaned of scale, plaque, etc. When everything is finished, you will need to reassemble everything in the reverse order.

If the problem appears in the shower and after cleaning the faucet there is still no hot water, you will need to clean the sprayer. It is dismantled using an adjustable wrench, after which it is placed in a pan and filled with water, and then placed on the stove. You need to add vinegar or citric acid to the water. No need to boil. An acidic environment has a destructive effect on plaque and other deposits that have formed on the sprayer. After cleaning, the sprayer should be rinsed under running water and returned to its original place.

If the problem is not in the mixer, but in the water pipes, then it is better to contact a specialist (fitter, plumber).

In order to fix the problem of poor water pressure yourself, you will need:

• turn off the water;
• remove the coarse filter plug;
• remove and wash the wire cassette.

The filter element is returned to its place and the plug is screwed in using a special tape for sealing. If the reason was not a clogged coarse filter, we can assume that the failure of the fine cleaning system is to blame.

After disconnecting from the water supply, you need to check the pressure in the free pipe. To do this, you need to open the central valve slightly. If everything is normal, replace the liner and wash the filter bowl of accumulated dirt, and then put everything back in its original place.

When none of the above helps, you can try power flushing the pipes. To do this, turn off the water with the valve located near the filter, unscrew the flexible hoses or the mixer, if it is wall-mounted.

Water will flow from the pipes, which must be directed into the sewer or a pre-prepared container (basin, bucket). It is recommended to do pipe cleaning with an assistant. You will need to sharply open and close the valve for 1-2 seconds.

Weak pressure from a faucet can upset even the most level-headed homeowner. After all, the duration of filling a kettle or coffee maker and the performance of a washing machine or dishwasher depend on the pressure.

In addition, if the pressure is poor, it is almost impossible to use either the toilet, shower or bath. In a word, if there is no pressure in the tap, then there will be no comfortable living in the house.

We understand the reasons for low water pressure in the tap

What weakens the water pressure in the tap?

We have already discussed why weak water pressure in the tap can ruin even the happiest life even in the most perfect house or apartment. However, moaning will not help the grief. Moreover, this problem is not as terrible as it seems. You just have to understand what weakened the pressure, and you will get an almost ready-made recipe for eliminating this trouble.

In this case, the list of TOP 3 reasons for a drop in hot or cold water pressure is as follows:

• Faucet clogged . In this case, the intensity of the water jet is weakened by a plug of rust and scale that has clogged the aerator, filter insert (mesh) or axle box. Moreover, only one tap in the house suffers from this problem. That is, if your tap water flows poorly, for example, in the kitchen, but there are no problems in the bathroom, then you will have to disassemble and clean the problem point of consumption.
• . In this case, the same particles of silt, rust or scale are to blame. Only now they are not blocking the faucet aerator or faucet mesh, but the filter built into the water supply. In the worst case, such deposits can block the flow diameter of the connecting fitting or the pipeline fitting itself.
• . In this case, the cause of the weakening may be either a failure at the level of the pumping station or depressurization of the pipeline. A failure at a station can only be corrected by utility service repair teams. An indicator of this breakdown is the lack of water in the entire neighborhood. Loss of tightness is diagnosed visually - by a stream of water gushing from the body of the water supply fittings. Any mechanic from a service company can fix this breakdown.
• In addition, speaking about the reasons for the weakening of pressure, it is necessary to mention possible miscalculations when installing a specific water supply line . Incorrect diameter (larger than the previous branch), excessive length (inappropriate for the characteristics of the pressure equipment) - these are the most important reasons for the drop in pressure in the new water supply network.

If you don’t want to deal with them, order a water supply project from professionals.

Well, now that you already know the reasons for the drop in pressure in the tap, it’s time to figure out ways to eliminate this water supply defect.

What to do if cold and hot water from the tap does not flow well?

It all depends on the reason for the drop in pressure.

For example, if your faucet is clogged, you will have to do the following:

Removing the faucet aerator for cleaning

• Take an adjustable wrench and unscrew it from the spout of the faucet. – foaming water jet nozzle. This part has very small nozzles. Therefore, aerators are clogged every six months. And if we are talking about a faucet mixer with hot/cold water, then the frequency of cleaning the nozzles is reduced to 2-3 months. The dismantled aerator is washed under running water.
• If the aerator is clean and the water flows weakly, you will have to dive even deeper into the faucet design . Indeed, in this case you need to get close to the locking unit - the axle box. To do this, you need to dismantle the valve (faucet handle) and unscrew the lock washer holding the locking element in the body seat. Next, you remove the locking assembly from the body and clean off any deposits of silt or scale from its surface. In the final, you will have to assemble the crane using the reverse procedure.

Before dismantling the faucet shut-off unit, be sure to shut off the water supply by closing the water valve closest to the point of consumption. Otherwise you will flood the entire apartment.

• If the source of the problem is not the faucet, but the “spray” in the shower stall or bathroom, you'll have to do things a little differently. First, turn off the supply to the sprayer. Then remove it from the stand or metal hose using an adjustable wrench. Immerse the removed part of the sprayer in a saucepan with vinegar. Warm up this medium on the hotplate. Rinse off the scale with water. Return the nozzle to its place.

If the smell of vinegar irritates you, try a 10% citric acid solution. To prepare it, it is enough to dissolve 100 grams of dry acid powder - it is sold in any confectionery department - in a liter of water.

If you don’t want to tinker with the crane, call a mechanic from the management company. He will solve this problem right before your eyes.

We hope you already understand what to do if there is poor water pressure in the tap.

Now let's move on to the pipes:

• First, turn off the water by turning the central valve near the meter.
• Next, remove the coarse filter plug. Remove the wire cassette and wash it in a container. Then return the filter element to its place, renew the seal and screw in the plug.
• After checking the coarse filter, proceed to checking the fine cleaning system. First, disconnect it from the water supply and check the pressure in the free pipe by slightly opening the central valve. If everything is in order, change the liner, simultaneously rinsing the filter glass from particles of accumulated dirt. In the final, everything, of course, is mounted in its original place.
• If the filters are cleaned, but water still does not come out of the tap with the required force, then the reason for the drop in pressure is a blockage in the pipes themselves. Locating this problem and eliminating it is an extremely time-consuming task. Therefore, after cleaning the filters without results, you will have to call the management company and report a problem with the passage of pipes in the water supply.

If you have not changed the wiring of the water supply system in the apartment, the management company will pay for cleaning the pipes. After all, it is she who must monitor the performance of the “native” engineering communications.