Hot water is replaced by cold water. Why hot water flows from a cold tap: causes, consequences and solutions

Plumbing often fails. One of the most annoying problems with her - hot water from a cold faucet. This is not only extremely inconvenient, but also fraught with burns. It is impossible to ignore the breakdown, otherwise the situation will only worsen in the future. Why does hot water flow from a cold faucet? What troubles can lead to malfunctions in the water supply system? How to find and fix a breakdown? Consider the most common and available ways independent decision Problems.

In some cases, apartment owners are even happy that they get warm water for the price of cold water. This is a big mistake. You should immediately find the reason why hot water flows from a cold tap. Plumbing equipment for cold water supply is not able to withstand high temperatures for a long time. It breaks down, and repairs are many times more expensive.

Standard two valve mixer

The consequences may be:

• Breakage of flexible pipes. Faucet connections may fail. As a result, leaks will appear, it will be necessary to change the tubes.

• Mixer problems. It will completely or partially cease to perform its functions. The only way to repair a broken faucet is to replace it. This is an extra expense, because malfunctions can be prevented.

• Violation of the plumbing. Often, water meters, filters, drain cisterns toilets.

• Clogged pipes. Prolonged bursting of hot water can lead to breakage of the pipeline. In this case, it is very difficult to find out exactly where the plug has formed, and then the pipes are cut into pieces to replace the desired section.

• Large consumption of electricity. One of the reasons for the breakdown is the lack of a check valve on the water heater in front of the meter. Hot water from the device is supplied to the mixers not only in the apartment where it is located, but also to the neighbors. The heater is constantly turned on, which leads to increased power consumption.

Where does the hot water mix - find out

Water supply system apartment building equipped in such a way that it is not always possible to clearly determine where hot water is mixed. Often the "heroes of the occasion" themselves do not know that it is their plumbing that is faulty, and the entire entrance is suffering.

Define desired apartment quite simple: you should close one of the cold water shut-off valves in the entrance, and open the taps in this apartment for supply cold water. If water flows from a faucet, then it is broken. So you can check the plumbing fixtures in all apartments.

If shutting off the taps does not work, then the cause of the problem may be in the pipeline. In this case, the tenants will have to turn to the utilities or the management company for help.

Causes of hot water in a cold faucet

There are several reasons why hot water flows from a cold faucet:

• Pressure difference in pipelines of hot and cold water supply (DHW and cold water). If the plumbing is not connected correctly or is faulty, hot water “presses through” cold water.

• Malfunctions in the mixer. All appliances wear out, and faucets are no exception. Over time, they break down, which can lead to hot water mixing with cold water.

• Problems with hygienic shower. If it is defective, incorrectly connected, or if the owners make mistakes in operation, this may lead to a malfunction of the system.

• Errors in connecting the shower. Often, owners save on the services of professional craftsmen and connect plumbing on their own. This is fraught with trouble.

• Incorrect connection or operation of the water heater. Hot water from the boiler can be mixed with cold water if not installed or defective. check valve.

We fix problems with our own hands

Not in all cases it is possible to fix the breakdowns on their own. However, this is quite possible if the malfunctions are insignificant. Below we consider the most simple ways do-it-yourself plumbing repairs

Advice. If there is no confidence in own forces, it is better to contact professional craftsmen. Paying for their services will cost less than re-repair.

Option 1: fixing a broken faucet

• Gasket wear. This is the easiest repair. The gaskets most commonly worn are on semi-turn faucets and faucets that have shower diverters. You need to replace the seal, and the problem will be solved. You can buy a new gasket at any hardware store. Before replacing, turn off the water supply to the apartment, then remove the old gasket, install a new one and assemble the structure again.

• Seal wear. To access it, remove the tap knob, then the decorative cap. The crane box will open, and above it is a hexagon, with which you can unscrew the nut and get to the stuffing box. By the way, often it does not even have to be removed, it is enough to tighten the nut more tightly. If this does not help, you need to replace the gland packing and reassemble the valve.

Note! A damaged gland will very rarely cause hot water to flow from a cold faucet, but it's worth checking.

Step-by-step instruction for seal replacement

• Removal of the mixer itself. Devices don't last forever. If the mixer is old, then it is better not to repair it, but to replace it immediately. Repairing worn metal is pointless.

• Faucet mixer. Sometimes the mixer is simply defective, and the problem arises due to the poor quality of the casting. Such a plumbing fixture should be changed in the store, and if the gasket is dry, you can buy a new one.

Advice. If the mixer is single-lever, you will have to replace the cartridge. The old one is unscrewed and thrown away, and a new one is installed in its place.

Option 2: if the problem is in the hygienic shower

AT last years apartment owners are increasingly installing hygienic shower. This is a simplified version of a bidet for bathrooms where a full-fledged plumbing fixture does not fit. Such an “upgrade” of the toilet bowl is very functional, but not everyone uses it correctly. This may be one of the reasons why hot water flows from a cold faucet.

In order for water to start flowing from the shower, press the start button on the mixer. When the procedure is completed, you need to release the button, close the valve. Many people forget to perform the last step, because the water stops flowing after pressing the button.

If the mixer is not closed, hot and cold liquids are still mixed in it. At the same time, it does not flow out of the hygienic shower, but enters the system. At the moment when a tap opens in a neighboring apartment with cold water, the pressure drops, and hot water enters through a pipe designed for cold.

Advice. When buying any plumbing fixture, carefully read the instruction manual, even if you are sure that you know exactly how to use it.

Option 3: when the water heater fails

Why does hot water flow from a cold faucet? If a non-return valve is not installed on the boiler, it will still have to be installed after the shut-off valves so that there is no mixing of hot water with cold water. But sometimes warm water enters the cold water system when the valve is installed and in good working order. The reason is the incorrect operation of the water heater.

To use the water heater, close the hot water shut-off valve. Otherwise, the water will go into the cold water system. When turning off the water heater, close all valves and taps so that they do not affect the pressure in the system.

It happens that the reason why hot water flows from a cold tap is utility services. In this case, it makes sense to contact them for help. This does not always give the expected effect, so you should be prepared for drastic measures - the rejection of centralized hot water supply. Can install electric heater, counters and no longer depend on service providers. These are considerable expenses, but they always pay off, because your own nerves are more expensive.

Anatoly. St. Petersburg

Hot water often flows from both taps in my bathroom. I know that the most popular joke of my friends is now suggesting that I was lucky, but believe me, there is no happiness in this. Explain why hot water flows from a cold faucet?

Sometimes it happens that there is a violation of the water supply and you need to quickly find out the reason why hot water flows from a cold tap.

It is difficult to independently understand the causes of such an unhealthy phenomenon, but the master puts on the root cause as soon as possible.

But, if there is no desire or opportunity to turn to professionals for help, determining the source and solving the reasons that caused it can be caused by a number of certain difficulties and take a significant amount of time.

Causes of water supply disruption

When hot water flows from a cold tap, instead of ice water, this is extremely unpleasant and such a phenomenon should alert any tenant. It is impossible to ignore the fact that the tap water has changed temperature, as the reasons can be varied.

The most easily solved is the confused marks when installing the mixer, it is easy to determine this - cold water flows from the hot tap, and hot from the blue one.

This situation is resolved as soon as possible. But if this is not the case, then such connivance does not lead to anything good, especially when hot water is supplied centrally.

In the event that city services are involved in the supply of hot water, you should immediately contact the housing office, or another relevant institution that provides the house with a resource.

Solving the problem when heated liquid flows from both taps is their direct responsibility, since a leak, especially when a home is equipped with a hot water meter, can cause significant damage to the tenant's personal finances.

The cost of hot water supply is 5-8 times higher than the cost of cold water supply. Thus, it is not only pointless for tenants to hide the violation, but it is also extremely profitable to correct it.

Nevertheless, according to many statements of ordinary citizens, such a water supply issue can be resolved by the public utilities for a fairly significant period of time and, as a result, not be resolved.

So, if the services are in no hurry to resolve the troubles that have arisen, and warm water continues to flow from the tap, which is responsible for the cold water supply of the dwelling, you need to look for methods and ways on your own.

The main causes of violations of hot and cold water supply

Even a weak level of water heating from a cold tap should make residents think that there is some kind of problem in the city water supply system, which concerns the communications of a particular house, riser, or a single dwelling.

There are three reasons for such problems:

1. There are some pressure disturbances in the water supply system - in the hot water supply system, the pressure indicators significantly exceed the pressure indicators in cold system. It is also possible that there is no pressure at all in the SSH.
2. On outlets of hot and cold water to apartments, check valves have been dismantled.
3. Plumbing fixtures in the dwelling are faulty, or their outlets are incorrectly connected (when instead of hot from the red tap it is cold and vice versa).

Each of the problems requires a separate and more extended description.

Pressure drops

Because of some design features, the pressure in the hot water system is slightly higher than in the SHV.

When during operation the cold pipeline becomes clogged faster than the hot one, disturbances can occur and a huge difference in the pressure levels of adjacent systems is manifested.

Also, it is likely that repair or preventive work is being carried out on one of the sections of the cold pipeline.

As a result, there is no pressure at all, and hot water penetrates cold pipes and pours out of cold taps.

Also, the reason for the pressure difference may lie in the not entirely correct location of the pipelines - during the installation of communications, the dependence of height and pressure was neglected.

The pressure difference is the main condition for the mixing of hot liquid into a cold riser and faucet.

No check valves

The absence of check valves is a common phenomenon, since they began to be mounted relatively recently.

AT apartment buildings they were not provided for by the Soviet construction - valves of this kind are installed in conjunction with meters to account for water consumption. The device of the valve is such that nullifies all possible ways winding counters.

The absence of such a device on a hot riser does not fundamentally solve anything.

Problems begin when the valve is not installed on the cold riser, which means that the liquid can flow in any direction, without obstacles in its own way.

Also, it should be noted that there is a dependence on the level above the ground - the higher the floor, the stronger the effect of the absence of a check valve will be and the more noticeable will be the admixture of hot water in the cold riser.

The dependence on the floor can be explained by the fact that it is easier for cold water to go down than to go up.

But, separately, the valves cannot affect the mixing of water of different temperatures in the risers - somewhere there must be one, or else - several, places in the dwelling in which the risers are in contact more than is necessary.

Incorrect plumbing connection

At a particular point in time, there are practically no separate taps for hot and cold water in the apartments. Residents prefer combined options - mixers. Faucets are not always installed with two handles.

Often, rotary single-handle variations of mixers are purchased and mounted, otherwise - cartridge ones.

Direct malfunctions of cartridge mixers can lead to the addition of hot water to cold water.

The problem of hot impurities in cold water may also be due to the connection of a mixer with a violation of technology.

This happens due to the inexperience of the person who performs the repair event. To prevent this from happening, you need to use installation services from knowledgeable people.

There is a possibility that something in the faucet is out of order.
The main causes of hot admixture can be:

• worn seal;
• wear of the entire mixer;
• cranebox defect;
• factory defect of the crane;
• pad wear.

Each of these reasons can be a source of problems. But there are some parts that fail earlier and more often than others.

For the most part, it is the damaged gasket that is responsible for the fact that hot liquid enters the cold liquid.

Since the gasket is made of rubber, under the influence of high temperatures it can deteriorate very quickly.

Then, when parsing, a piece of rubber stuck to the metal of the internal parts of the mixer is found. When the gasket is stuck, it should be immediately replaced with a whole one.

Moreover, such a structural part of the mixer is a consumable that needs to be replaced with enviable regularity.

Only exceptional gasket models can last more than 5 years of active use of the crane.

The second frequent, according to statistics, the reason is the wear of the mixer. There is no way to eliminate such a nuisance as simply as the last one.

It cannot be fixed, the only option is to purchase a new serviceable crane and install it in place of the failed one. Ideally, if a professional is involved in replacing the mixer.

Oil seal wear is rare, but it also happens. In order to check its condition, you should disassemble the mixer - unscrew the stuffing box nut and inspect the part.
If necessary, replace it with the performance of each necessary action:

• gland nut unwinds;
• special tow, lubricated with a certain agent, is wound thin layer on the valve stem;
• nut is tightened.

Rarely, but it also happens that a factory defect in the mixer is to blame. It can be expressed in the fact that the axle box crane is initially faulty, or there is some other violation.
Quite often, factory defects can be expressed by such problems with the mixer:

• the sealant dries up with enviable regularity;
• the size of the seal does not match the product;
• there are cracks and other initial damage on the inside of the mixer.

As in the case of a worn mixer, it is required complete replacement plumbing device. If the marriage was detected in a timely manner, then you need to contact the store where the product was purchased and demand that it be replaced with a serviceable one.

It is extremely rare that the axle box crane fails - in this case it is necessary to replace it.

When choosing a new component for the mixer, it should be remembered that axle boxes on domestic models and axle boxes on imported ones cannot act as a substitute for each other.

Regardless of what exactly caused the replacement of cold water with hot liquid, you should begin to deal with the misunderstanding that has arisen as soon as possible - in any case, the first adequate step would be to call the housing office and find out if they know what the reason is. And then you should act according to the situation.

Ask an expert in the comments

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As practice shows, not only a person can go to extremes, but also equipment created by his hands - for example, plumbing in an apartment. Either you don’t get hot water from him at all, or it runs from two taps at once. Yes, yes, and this happens in life - it should be noted that such incorrect operation of the water supply system is not a rare occurrence. Yes, what can you say about this, since you have landed on this page of our website, you have probably already encountered this problem yourself. This is what we will try to solve in this article, in which we will deal in detail with the question of why hot water flows from a cold faucet - we will talk about the most common reasons for this behavior of the faucet, the consequences that such behavior may be fraught with and how to fix this problem.

Hot water flowing from a cold water faucet

Why hot water flows from a cold tap: reasons

Oddly enough, there are a lot of reasons why hot water can run from a cold tap in a mixer. The culprit of such a celebration may be not only the mixer itself, but also other equipment installed in the apartment. Moreover, it may not even be you or your plumbing that is to blame - this is a disease apartment buildings, and any of your riser neighbors can be the instigator of such a nuisance, without even knowing it. Among the most common reasons why hot water flows from a cold water faucet, the following points can be noted.

1. Failed mixer. They can be both from the old age of this plumbing fixture, and due to factory defects. At least four common faucet problems can be counted - gasket wear, gland wear, faucet body wear and factory defects, and in most cases it consists in poor-quality gaskets that can be dried out from time to time or simply do not fit the desired size.
2. Improper plumbing. The simplest and most common example is . People try to simplify everything and instead of completely closing the mixer, they simply turn off the tap on the shower - as a result, due to the pressure difference in the pipes of cold and hot water, a banal squeezing occurs. The same thing can happen with a conventional bath faucet, when a person turns off the water not with a tap, but with a switch on, setting it to an intermediate position.
3. Incorrect plumbing connection. As a rule, it is either , or . In the case of the first plumbing fixture everything rests on improper assembly by amateur craftsmen - when the booth and all its hoses are connected not at the factory, but manually at the place where the booth is installed. In case of electric water heater it is the absence of a check valve - when your neighbor turns on the cold water, the pressure drops in the riser, and hot water from your boiler rushes to make up the pressure difference.

More about the situation with hot water in a cold faucet, see this video.

Some may find this behavior home plumbing not critical - on the contrary, some people may see certain advantages in this. I hasten to slow you down a little - the consequences can be very sad. We will talk further about what can happen if the causes of squeezing cold and hot water are not eliminated.

What water flows from the tap: cause - effect

As mentioned above, ignoring such a breakdown as hot water in a cold tap does not bode well - moreover, the consequences of such an ignorance can be very unpleasant. The thing is that in most cases, equipment designed for cold water does not withstand prolonged exposure. high temperature. As a result, you may get the following troubles.

In addition, if the presence of hot water in a cold tap is due to the absence of a check valve on the water tank in your apartment, this is fraught with huge energy consumption. Judge for yourself - instead of providing hot water only to your apartment, you will supply it and all your neighbors in the riser. In general, the consequences are by no means rosy - as you understand, it is better to deal with such a problem right away. Great solution in such a situation, check valves will be installed directly in front of the meter, at the inlet of the water supply to your apartment.

How to fix a breakdown: we analyze common options

It is not surprising to guess on your own that each type of breakdown has its own characteristics in the elimination. The easiest way is to eliminate imperfections - for example, if yours is not equipped with a check valve, then you just need to install it, while observing the direction of installation. Another thing is if we are talking about a full-fledged one. Take the same mixer. Not every person will be able to immediately figure out what and where to unscrew, change and then spin again. Here we need help, which we offer to your attention.

So, the main breakdowns of the mixer, associated with the solution of the question of why boiling water is pouring from a cold tap, are eliminated as follows.

Things are somewhat different with single-lever ones. Here the medicine is only the bottom - replacing the cartridge. It is performed very simply. First, we turn off the water, then remove the lever by unscrewing the screw hidden under the cap with a blue and red dot. Then we unscrew the decorative cap, under which the nut is hidden big size. We unscrew it and take out the cartridge - accordingly, we go to the store and buy a similar one, which we install instead of the old one, after which we assemble the mixer in the reverse order.

And in conclusion, the topic of why hot water flows from a cold tap, I will say a few words about troubleshooting. It has already been said above that such a problem usually concerns the entire riser, and not a single apartment - at least in standard situations when check valves are not installed in any of the apartments. So, if you don’t want to mess around with neighbors, who, as a rule, are not distinguished by loyalty, you just need to install check valves at the water inlet to the apartment - if it’s in your apartment, then, accordingly, hot water in neighboring taps will turn into cold. In a good way, check valves should be mounted together with meters in each apartment - their presence guarantees that a question like the one discussed above will not arise.

Residents of city apartments often face minor problems with plumbing equipment. And calling the masters to eliminate them is not always cost-effective. Sometimes it's easier to find the cause on the Internet and try to fix it on your own. If hot water suddenly flows from a cold tap, most likely the residents are to blame. This phenomenon can have several causes and solutions. Some of them will require time, and in some cases you will have to invest more money. Consider what can be done if going hot cold tap water.

main reason

If hot water flows from a cold faucet, there may be several reasons. By itself, hot water cannot get into the cold water pipe. Pipes with heated and cold water have different pressures, in the DHW channel it is greater. But due to incorrect connection or operation of appliances, hot water under more high pressure displaces the cold from the pipe.

Unfortunately, this phenomenon affects not one apartment, but all floors with a common riser. If such a problem arose, it is not a fact that the reason is in your apartment. We have to think together with the neighbors why from a cold tap it's warm water. You can check this as follows: at the entrance to the house, close the cold water shut-off valve, then open the cold water tap in all apartments. If nothing flows, then everything is in order. Where water has flowed, you need to look for a malfunction.

If, during the check, none of the residents has water, then the reason lies in the pipeline. You need to ask the neighbors which of them has recently installed the plumbing. If this was done incorrectly, with an increase in pressure in the pipes, squeezing occurs and hot water displaces cold water.

Incorrect operation of the bidet

A bidet is a hygienic shower. To pour water, you need to open the mixer and press the button. After graduation water procedures press the button and close the valve. But many simply turn off the button, leaving the mixer open. At the same time, hot water is mixed with cold water and flows from the taps in this form. Neighbors can turn on cold water, then the pressure in the system drops. Therefore, hot water will displace cold water.

Due to the pressure difference, hot water flows through cold pipes. To avoid this, remember to close the bidet mixer.

Incorrect boiler connection

Due to poor-quality installation of the water heater, such a problem can also occur. If you have recently installed a boiler, then you do not need to think for a long time why the malfunction occurred. Just check the installation is correct - if there is no check valve, heated water will enter the riser with cold water. Due to pressure drops, the water heater itself may break. Usually a check valve is placed under the water tank after the shutoff valves.

It is very important to use the boiler correctly. Before use, it is necessary to close the DHW valve and unscrew the inlet and outlet taps. If the valve remains open, then the heated water will go into the cold water pipes.

To avoid squeezing in the pipes, after using the boiler, repeat the steps in reverse order. Close the inlet and outlet valves and open the shut-off valve.

Incorrect mixer installation

Often apartment dwellers are on their own. If this is done by an inexperienced person, he may install the tap incorrectly. The whole secret is to carefully tighten the mounting washer. That is why the installation may fail, and instead of cold water, hot water will flow.

If you are sure that the mixer is installed correctly, it is quite possible that it has deteriorated during operation. Most often this happens with old cranes installed back in the Soviet era. Over time, the following breakdowns occur:

• The gasket rots.
• The mixer cartridge is leaking.
• The seal wears out.

Also, the cause may be a factory defect in the mixer. Unfortunately, this is not uncommon, so it is better to choose high-quality fittings for which the manufacturer provides a guarantee.

Gasket wear

This problem occurs in most situations where hot water flows instead of cold. Rubber gaskets they can serve in mixers for 10 years, but according to the rules, it is worth changing them every 2-3 years.

An indicator that it is time to change the gasket is the buzz of an open faucet. Over time, the rubber shrinks and the water begins to vibrate from strong pressure. This is where the annoying sound comes from.

You can change the gasket yourself.

1. Shut off the water.
2. Remove the mixer, disassemble it and remove the gasket.
3. Install the new rubber in place.
4. Assemble the faucet, install it and turn on the water.

If the unpleasant sounds disappeared, and from the cold tap goes cold water means you did everything right.

Mixer wear

If replacing the gasket did not help, the mixer will have to be disassembled again. You need to check if the gasket was installed correctly. When you are convinced of the correctness of your actions, but hot water is still coming from a cold tap, you need to change the mixer completely. In modern faucets, other parts that cannot be repaired may wear out.

Must choose quality device so that it does not break immediately after installation. It is better to give preference to reliable manufacturers.

Oil seal wear

If everything is in order with the tap closed, and no water flows anywhere, and when the cold valve is open, hot water comes out, then you need to change the stuffing box. It could wear out from long-term use.

Fixing this is easy enough. Here's what to do:

1. The gland nut is unscrewed with an adjustable wrench.
2. Tow, lubricated with oil or grease, you need to wrap the valve stem with a thin layer.
3. After that, the nut is screwed back. You need to do this carefully so that the water continues to flow from the tap as usual.

Another option to resolve the issue is to change the gland or valve entirely.

Faucet factory defect

If you have done all the described procedures, but instead of cold water, hot water still flows, then you should not exclude a factory defect of the mixer.

Usually the defect lies in a bad seal, which is inaccurately sized, or in cracks and low-quality parts of the mixer. A new crane with defects can be exchanged in the store for another one.

Effects

If the cause of this phenomenon is the incorrect installation of plumbing, then the tenants are to blame. Consequently, Management Company is not responsible for damage caused by this problem.

Boiling water from a cold water tap is unpleasant, but there are other consequences. For example, some appliances are not designed for exposure to hot water. These include:

• Toilet bowl.
• Cold water pipes.
• Toilet flush mechanism.

If these items become unusable due to your fault, then the responsibility lies solely with you.