Non-return safety valve for boiler. Why is a safety valve needed in a water heater? Safety valve installation

The safety valve, or check valve in water heaters, is used to relieve excess pressure generated when heating water. The valve consists of a spring that is designed for a certain pressure; if the pressure is exceeded, the spring is compressed and water comes out through a special spout. In order to choose correctly and buy safety valve water heater Customers ask us numerous questions about the device and its operation, the answers to the most important ones are below:

Why is my water heater valve leaking?

What are the criteria for selecting a valve for a water heater?

1. Connecting thread, in domestic water heaters thread 1/2 inch, industrial 3/4.
2. The pressure for which the valve is designed (6.0 Bar or 8.5 Bar) must be the same for which the welds of the internal tank are designed; the maximum pressure of the boiler can be found in the product data sheet or on the nameplates on the body of the water heater.
3. We recommend installing valves with a lever for manual reset, simply because it is convenient and you may need it sooner or later.

How can you tell if the valve has failed?

1. If water simply pours out of the valve or drips heavily even without heating, but you are sure that there is no excess pressure in the system, then the valve must be replaced.

Where is the valve placed on the water heater?

1. The valve must be installed only at the inlet cold water directly in front of the tank itself.

Is it possible to drain water from the tank through the valve spout?

1. The valve is not intended for draining, since the water in the tank has impurities, scale, calcide, etc. passing through the spring of the spout in a large volume, it clogs it, which can affect the protective function valve
2. To drain, use a tee, which must be installed between the tank body and the valve.

Safety valve for water heater: design and principle of operation

Now we will figure out why a safety valve is needed in a water heater and what is the principle of its operation. We will also learn how to choose the right valve and buy it, then install it (installation) and what to do if it leaks.

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When installing a storage boiler, you must take care of operational safety and purchase a safety valve that protects the device from pressure surges, and, in the event emergency shutdown water, does not allow it to flow out of the container. What is a safety valve? Why is this part so necessary for a water heater? How to select and install it? You will find answers to these questions in this article.

Safety valve for Thermex water heater

What is it needed for

When water heats up, it expands and increases in volume, and the pressure correspondingly increases. If it exceeds the strength level of the boiler, it will simply explode. To prevent this from happening, a safety valve is installed. It does not allow the pressure inside the heater to rise above normal.

In addition to protection from possible accident, the valve performs the following functions:

• doesn't allow warm water return from the tank to the water supply;
• protects against;
• If the water supply is cut off, you will not need to refill the container with water.

If you think that your device will protect the thermostat, then you are mistaken. They control the degree of water heating and do not allow it to boil. However, like any other device, they can fail, resulting in irreversible consequences. Therefore, it is not worth the risk.

How it works and works

When talking about a safety valve for a water heater, it is better to use the phrase “valve system”, because there are two of them in the device.

Boiler safety valve device

They are located in a brass or nickel-plated body. At the bottom of the housing is installed, which, when the pressure in the system decreases, prevents the outflow of water from the water heater. In the perpendicular branch there is a second valve, thanks to which, at the moment of increasing pressure, part of the water is released through the fitting.

How does a safety valve work?

Principle of operation:

1. While the pressure is normal, the valve is closed and does not allow liquid to flow out; as soon as it becomes equal to the pressure in the water supply, the spring presses the plate against the protrusions of the body and blocks the flow of water.
2. When the heating is turned on, the water temperature gradually increases, and the pressure also increases with it.
3. As soon as the pressure exceeds the force of the spring, an outlet opens to a fitting through which excess water is drained. When the pressure returns to normal, the spring closes the passage and the flow of water stops.

Based on the principle of operation, it becomes clear that water will constantly drip from the fitting. To drain the draining liquid, you need to put a tube of the appropriate diameter on the pipe and secure it with a clamp. The pressure required for normal operation of the water heater is 6-10 Bar.

The tube to the fitting must be transparent so that you can monitor the operation of the device.

Kinds

Conventional safety valves are similar in appearance and differ only in small details, but they are responsible for practicality of use.

The figure shows two safety valves with release levers. They allow you to check (must be done monthly) the functionality of the device.

Safety valves for boilers with the possibility of forced pressure relief

The difference between the two modifications presented is that in the sample in the photo on the left, the lever is secured with a screw, which eliminates the possibility of accidental opening or full reset water.

Another discrepancy: the shape of the fitting. The sample on the left has an oblong fitting with a nonlinear shape. The hose is easy to put on and is long enough to install a clamp. But the fitting on the right model is short, with a widening towards the end. It will be very difficult to tighten the clamp on such a specimen.

The following figure shows relief valve without a forced pressure release flag. The model on the upper left has a screw cap. If necessary, it can be unscrewed and cleared of all kinds of blockages.

Safety valve without the possibility of forced pressure release

The sample on the right is the worst of the options, because it cannot be serviced. The only advantage of such models is their low price.

The above models are suitable for water heaters with a volume of 50-60 liters. For larger volume boilers, other models with built-in additional devices: ball valve or pressure gauge that control blood pressure.

Safety valve for large boilers

In such devices, the water discharge fitting has a standard thread, so the fastening is strong. Such models are distinguished by high quality and reliability, which is why they are not cheap.

How to choose

When choosing a safety valve for a water heater, pay attention to the following components:

• the temperature for which it is designed;
• threaded connections (usually half an inch);
• pressure;
• Is there a handle for forced draining in the design?

When purchasing a relief valve, be sure to check its pressure, because... this is one of the most important indicators. If you buy a device with a smaller size, you will constantly have to deal with the problem of water leakage. If it is larger, then it may be useless and will not protect the container from explosion.

Installation

Before you begin installing a water heater safety valve, be sure to drain the water from the unit and turn it off.

The location of the device is the cold water inlet into the boiler. The installation process is quite simple: using a 3-4 turn key using seals, the second threaded end of the valve is connected to the cold water supply system.

Be sure to check the direction of incoming water - it is marked with an arrow on the valve body.

If the water pressure constantly fluctuates and often exceeds the norm, then you must first install it.

Water leaks from the valve from time to time. This is an absolutely normal phenomenon, which indicates normal operation boiler, but not everyone likes it. In this case, the drainage pipe must be connected to sewer system through a flexible transparent hose, which will allow you to monitor the performance of the device.

Installed safety valve on the water heater

Some people do not want the valve to be visible and place it away from the water heater. Such manipulations are quite applicable, but subject to two important conditions:

• Shut-off devices must not be installed at the distance between the valve and the entrance to the boiler;
• a long vertical section of water supply will itself increase the pressure on the valve and unnecessary leakage may occur.

The distance between the valve and the boiler should be no more than 2 m.

Why is water dripping from the tap?

Dripping water indicates a faulty part, but even if water drips under high pressure, do not panic in advance. This can be caused by several reasons:

• spring stiffness is poorly adjusted;
• the pressure in the pipeline exceeds the norm.

In the first case, the malfunction could have occurred due to the fact that the installation was carried out by non-professionals. Many check valves are manufactured to allow the spring rate to be changed from the factory. The hardness must be adjusted by a specialist. If the settings have not been changed, then most likely the spring has weakened, in which case it is advisable to replace it with a new one.

If the cause of the breakdown lies in increased pressure in the pipeline, then before installing a safety valve, it is recommended to install a pressure reducing valve.

If there is excess pressure in the pipeline, you can install a pressure reducing valve at the entrance to the apartment, so you will immediately protect all the devices in your home.

You will spend very little money on purchasing a safety valve, but you will get safety and a long service life of the water heater.

Water heaters are installed not only in private houses not connected to the central water supply, but also in city apartments. Opportunity self-regulation temperature and comfortable existence during the period of planned repair work- these are the advantages of apartments and houses with boilers. Self-installation Such complex equipment requires strict adherence to all connection and safety rules. Since the electricity in the water heater is combined with practically boiling water, a safety valve is necessary.

Peculiarities

A water heater safety valve helps prevent excess pressure from building up inside the unit. When the liquid is heated to certain temperatures, the device must turn off the heating based on a signal from the thermostat, but in rare cases the sensor may not work or simply break. The design of the boiler requires tightness and closed taps, so if the water overheats and steam forms, occupying a larger volume, an explosion may occur. In this case, the safety valve allows you to relieve pressure to the standard level of 10 bar and normalize the operation of the entire system.

The functionality of the safety valve is not limited to this alone. It also prevents water from the water heater from flowing back into the supply system when it is empty. Any fuse consists of a body, a rod with a handle at the top, a spring and a plug. Marked on both ends of the body pipe thread with sizes ranging from 1⁄2 inches to 3⁄4 inches depending on the type of product.

Kinds

There are practically no special differences between the many types of safety fittings for a water heater.

Most often they are divided into three groups depending on the volume of the heating apparatus.

1. Valves for boilers with a volume of no more than 50 liters. This category includes standard disposable valves. They are almost always non-removable and their service life is very short. But their low cost allows, without any difficulties, to simply change such devices once a year.
2. Valves for boilers with a volume of no more than 200 liters. More serious devices that professionals recommend installing even on boilers with a volume of up to 50 liters. They consist of several valves for various purposes and an additional nozzle for sewerage supply.
3. Valves for boilers with a volume of more than 200 liters. These are serious, complex devices, including a pressure reducing valve, a device for draining water and various adapters. Most often, such shut-off valves are installed on large industrial heaters and are rarely installed even in large private houses.

In addition, safety valves may vary in the presence and operation of additional structural elements. For example, release handles.

Using this pen, you can check the operation of the valve as follows:

1. The lever is installed vertically.
2. He pulls the spring behind him.
3. The spring opens the flow of water.

This check should be carried out at least once every couple of months. The release lever is also used to completely drain the water from the tank. The handle must be held until the water drains completely.

For some models of safety valves, such a lever can be secured with a special screw, which prevents spontaneous opening when the spring is weakened. There are also valves without a discharge structure for forced drainage of water. Most often they have a lid mounted on a thread. Through it, the valve can be cleaned of scale and blockages.

ABOUT high quality the purchased product is indicated by the markings applied to it. For example, an arrow should be engraved or drawn on the body to indicate the direction of fluid flow. Also on the body there must be information about the maximum permissible pressure that the valve can withstand. Even professionals will not be able to distinguish between a four and six bar valve if information about this is not in the accompanying documentation. Of course, such a device will have a higher cost, but the priority should still be the quality of the entire system, and not its price.

In addition to the above, differences may be in the shape and length of the fluid outlet fitting. A long non-linear fitting without expansion at the end will be more convenient, since it is easier to put a hose on it and secure it with a clamp. In addition, sometimes instead of a safety valve, a blast valve is installed on a home boiler. It is designed to quickly remove water in an emergency and should not be drained multiple times. Although the functionality of these locks is largely similar, one cannot replace the other.

A boiler safety valve is often called a check valve, but in reality it is a completely different device, although they are similar in appearance. The check valve is responsible for the unidirectional flow of water, and the safety valve protects the pipe and water heater from damage due to excess pressure. Installing a return shut-off device instead of a safety shut-off device may cause damage to the property and health of the occupants. A device for unidirectional water flow will not be able to stop the heating of the liquid above the boiling point if the thermostat fails and will not prevent an explosion inside the device, which will destroy not only the boiler, but also the walls of the room.

Principle of operation

Standard water heater fuses consist of three independent valves:

• the safety valve itself (in rare cases, explosive);
• check valve;
• drain valve.

The safety valve includes a metal rod, a plug at its end, a powerful spring and a fitting for draining the liquid. As soon as the pressure inside the boiler exceeds the value specified in the documents, the device is triggered, the rod will compress the tight spring and it will allow water access to the fitting, through which it will flow out. This happens so smoothly that the flow of water is simply a large number of drops

The check valve includes a plastic rod with a rubber plug at the end and a weak spring. Unlike water pipes, a boiler check valve is not designed to hold water pressure high pressure and serves as an ordinary damper, which is why the spring is so weak. It just prevents water from leaking into the pipes in the event of an emergency or a water outage in the central water supply.

The last, but very important valve is the bleed valve. It consists of a rod check valve and a small spring. He works “on the safety net.” When the pressure approaches critical values, but does not exceed them, the drain valve is able to normalize the pressure inside the heater when turning on the water tap or flushing the toilet. When the water in the pipeline slightly reduces its pressure due to this, the drain valve opens and the excess almost boiling water goes back into the pipe.

Installation

Before you bet safety fittings for an installed water heater, you need to study the supply of the construction market and choose a quality product.

Good valves have several distinguishing features.

• The body of a good unit is made of brass alloy using seamless casting. Sometimes it is plated with nickel to protect it from corrosion and scale formation. Unlike cheap copper or aluminum alloys, brass is heavier, making it easy to identify.
• When you press on the stem of a high-quality shut-off valve, you will notice how the plug moves tightly inside the body. Even a slight jamming at the end is allowed.
• A bad valve can be identified simply by blowing into it. If, even with strong pressure on the rod, air comes out freely, then it is better not to take the product. At the same time, if water periodically drips from the fitting of the installed constipation, this does not mean that it is broken. Perhaps you just need to clean the sediment plug and everything will work again.

If you follow these tips, you can choose the right fuse the first time and start installing it right away. There are few requirements for it. The valve is always installed in a line with cold water. It is placed between the shut-off valve and the pipe entrance to the boiler body. You can cut it directly into the water supply pipe or install a special tee at a distance of no more than 200 cm from the entrance to the heater.

Apart from the fuse, there should be nothing in this area. Most models are installed in such a way that water enters them vertically from below. There should be an arrow on the fuse body indicating this movement.

A polyvinyl chloride tube is attached to the fuse fitting, connecting it to sewer pipe. It is better if this tube is transparent - you can see whether the device is working properly.

The installation process itself is divided into several stages.

• Disconnecting the installed boiler from the power supply and draining the water from the tank. You need to make sure that the water supply to all pipes is shut off, otherwise, at the time of cutting the required area, you can simply flood all the apartments located below.
• The valve body is purged with air to remove any debris or dust. Tow or FUM tape is being prepared, which will serve to waterproof the threaded connection.

• wrench the valve is screwed into the junction of the pipe and the boiler. The arrow on the valve body must coincide with the direction of fluid movement. The union nuts must be well tightened; the joint can be additionally coated with silicone sealant.
• Before connecting the boiler to the electrical network, it is worth testing the connection using cold water. If after 5 minutes of liquid flow no drops appear at the connection site, then everything is connected correctly.

The safety and check valves are also checked “cold”. In the first case, you need to press the trigger flag weakly at first (the first drops of water should appear), and then with full force. When fully pressed, water should flow quickly through the transparent outlet tube. The check valve can be checked by filling the water heater reservoir completely and shutting off the central water supply. When you open a tap in the bathroom or kitchen, the flow of water should stop quickly. If water continues to flow from the faucet for several minutes, the check valve needs adjustment.

Sometimes individual elements of the water heater or the entire system stops working properly. This reduces the safety of the structure and can lead to dire consequences. In this case, you need to find out the cause and location of the breakdown as early as possible and either fix it yourself or call a specialist for this. Most often, thermostats, heating elements and safety valves fail. Moreover, a problem in the work of one of them can instantly affect the others. You should never install elements that do not match the parameters of the boiler or have different ways connections.

Problems cannot occur on their own; they have certain causes.

Most often they consist of the following.

• Late replacement of damaged parts. For example, the check valve should be replaced at least once a year. It's cheap and won't cost you much.
• Incorrect installation of the entire system. If the fuse is inserted into the pipe with insufficient waterproofing or at too great a distance from the entrance to the boiler, the system will not work properly.
• Voltage fluctuations in the electrical network can lead to failure heating elements systems.

• Presence of manufacturing defects or lack of preventive inspections. In order to choose the right heater and fuses, you need to carefully study all the information when purchasing. And even the highest quality device needs to be checked periodically.
• Scale formation or corrosion. Scale and corrosion on the check valve can cause water to leak back into the pipeline or “corrode” various connections, breaking their tightness.

The most basic faults can be divided into several types. Most often the broiler begins to leak. This can be either a manufacturing defect or a crack acquired due to corrosion. Such a tank cannot be fixed on its own; it will have to be completely replaced. Water dripping from pipe connections indicates they are leaking. On the contrary, water should sometimes drip from the safety valve. If it is always dry, it should be replaced.

Everyone knows that water expands in volume when heated. Its increase will be approximately 3-4% when heated from 10 to 80 ºС. In practice, this means that the volume of water of 50 liters will increase by another 1.5 liters. IN closed space storage water heater the pressure will inevitably increase to critical and can lead to its destruction. The safety valve for the boiler is designed to compensate for the expansion, which will be discussed in this article.

How does a safety valve work?

Structurally, the valve is a brass body in which 2 springs with disc locking elements are built-in. The first is installed inside the flow channel and acts as a check valve, preventing water from the boiler from flowing back into the supply pipeline. The diagram below shows how the simplest safety valve with release handle works:

Under the influence of pressure in the water supply, the spring is compressed and the disc element allows water to flow into the tank. After filling, the pressure on both sides is equalized and the spring returns the plate to closed position. If the network pressure becomes too low or disappears due to a shutdown, the water heater will remain full because the valve will not release water back.

The second spring of increased rigidity is located on the outlet; its task is to discharge water if a certain pressure is exceeded. This happens simply: the pressure force arising in the straight pipeline overcomes the stiffness of the spring, it compresses and the disc shut-off element opens the passage of liquid to the discharge fitting. The pressure value at which the safety valve with a check valve will operate is determined by the elastic force of the spring and is adjusted at the factory.

In fact, the valve combines 2 devices and is a mandatory attribute of every storage heater. Its main functions:

• do not allow excess pressure in the boiler tank by releasing excess water, protecting it from destruction;
• protection of the water heater from high pressure that may arise at the inlet from the water supply network;
• protection against water hammer, which happens in centralized networks water supply;
• do not allow water to leave the container when the pressure in the network decreases or disappears altogether.

Typically, electric water heaters are equipped with safety valves. But there are often situations when a separate purchase and installation of a valve is required, including for a boiler indirect heating.

The main criterion by which the device is selected is the maximum permissible operating pressure water heater. Its meaning can be found among technical characteristics specified in the product passport.

Important. When choosing a valve, you cannot rely on the pressure in the water supply network; it can fluctuate over a very wide range. Only the boiler’s passport data should be taken as a basis.

On the modern market, various manufacturers offer valves with response pressure from 6 to 10 Bar, with a setting increment of 0.5 Bar. To be completely safe, you can select a safety element whose response pressure is 0.5 bar lower than the maximum permissible specified in the documentation of the water heater.

In this regard, the choice of a safety valve for an indirect heating boiler is no different from the selection of a device for a conventional one. electric water heater, because the physical principles of liquid expansion operate the same everywhere. The only thing that can be recommended is to purchase a valve for the indirect heater with the ability to regulate the critical pressure. But such products are expensive, and their use is not always advisable.

Important. Do not confuse the DHW valve with a similar heating device. The latter are designed for lower pressure and are not intended for constant discharge of water.

The relief safety valve is installed on the cold water supply line to the boiler in accordance with the recommendations:

• Shut-off valves cannot be installed between the valve and the water heater, only American valves to disconnect the pipe;
• it is necessary to run a hose from the safety valve to the nearest drain;
• To conveniently empty the container, you can install a tee with a ball valve on the outlet between the valve and the water heater. How to do this correctly is shown in the photo:

Important. You cannot install a regular check valve instead of a safety valve, as some users do. The check valve does not protect the water heater from high pressure, but only keeps water inside the tank. How not to piping a boiler is shown in the photo below:

Usually there are no problems during installation; the operation is really simple. But further operation, when it constantly drips from the safety valve, raises many questions from users. You must understand that the operating mode, in which water periodically drips from the discharge fitting, is considered absolutely normal, and for this reason a tube is required that leads it to the sewer.

It is not normal for the pipe to leak all the time or never drip. The absence of drops may indicate a malfunction of the valve, so it is recommended to periodically forcefully release some water using the appropriate handle.

Note. The absence of water dripping does not always indicate a malfunction of the safety device. IN autonomous systems water supply from pumping station the pressure does not exceed 3 Bar and the valve may drip very rarely, so that you will not notice it.

There may be two reasons why the safety valve constantly leaks:

• product malfunction;
• too much high pressure in the water supply network.

In the first case, installing a new valve will help. But changing it to a device with a higher response threshold will be a mistake; you will expose your electric heater or indirect heating boiler to the danger of destruction. There are 2 ways: neglect and pay for extra expense water or additionally install a lowering pressure regulator at the entrance to the house.

How to adjust the safety valve?

In fact, all these devices have a factory preset, which is not allowed to be changed, and in most designs it is impossible. Nevertheless, there are valves with an adjusting screw; tightening or unscrewing it changes the compression force of the spring, and therefore the response threshold of the product. But remember that by changing the position of the screw in one direction or another, you have set the new critical pressure very approximately, and this is unreliable in terms of safety.

The correct way is to adjust the safety valve using the selection method according to the nameplate pressure and nothing else. Exception - adjustable devices with a scale applied, but there is no point in setting them, since the maximum operating pressure of the boiler is a constant value. Therefore, purchase and install quality products in accordance with technical requirements and they will serve properly for a long time.

Conclusion

Safety valves for boilers various types serve as safety features and are required to be installed. Here it is important to choose the right pressure element and follow all installation recommendations. Checking the functionality of the valve and its maintenance should be done together with flushing the tank, and if necessary, change it in time.

The main function of a non-return safety valve in a water heater system is to compensate for the increase in the volume of water in the tank during heating and to prevent its return to the water supply; an additional function is to protect against pressure drops in the supply line or the operation of heating elements in the absence of water supply. In the pipe junction diagram, it is located between the shut-off valve and the incoming pipe of the boiler; it is prohibited to place tees or other valve fittings in this area. Its presence is mandatory; this device serves as direct protection against emergency situations. The choice of a specific type of valve for a water heater depends on the volume storage tank, from the called manufacturers it is included in the standard kit, but if necessary, you can simply buy a replacement and install it yourself.

The design includes two parts, externally they resemble perpendicularly connected cylinders with different diameters. The larger one acts as a check valve and consists of three simple elements: plates, seats and springs. When cold water is supplied inside the water heater, it opens; after filling and the pressure exceeds the water pressure, it closes automatically. When hot water is consumed, the reverse process occurs and the tank is filled again. You cannot use only this type of protection, nor can you mount shut-off valves to turn off the check valve (leads to overheating of heating elements in an empty water heater). Cylinder with smaller diameter has a tighter spring at the moment when the internal pressure exceeds the standard? the drain opens and excess water is discharged to avoid spillage hot water a corresponding hose is connected to the open space.

Thus, the use of valves implies protection functions:

• From a drop in pressure in the supply line, water hammer and air getting inside the water heater.
• From overheating of the boiler and boiling inside the tank.
• Prevent hot water from entering the supply water supply.

The higher the volume of the water heater, the greater the amount of excess liquid is discharged. For example, for a 100 liter boiler this value reaches up to 3-4 liters per day. During operation, you should pay attention to possible signs breakdowns, in particular: poor transmission or its complete absence, leakage in cold mode.

Varieties

The main criterion when selecting a valve for a water heater is the operating water pressure (both in the water supply and inside the tank). Depending on the volume of the boiler, the following capacities are used: up to 50 liters, from 50 to 200 and above 200. Accordingly, the protection class is selected based on these indicators; experts recommend purchasing the most reliable devices for water heaters with a large volume, regardless of their cost. According to the principle of operation, all check valves are divided into direct and hinged. The first type is a disc valve with vertical movement (operates only under the pressure of the working medium), the second is located under the seat.

According to the degree of complexity, all return and safety components for a water heater differ in:

1. Non-separable - the simplest a budget option, the water is shut off due to the counteraction of a spring or disk. This is a classic check valve and nothing more, such protection is allowed only for water heaters with a minimum volume, its main function is to protect the heating elements from overheating when the tank is empty. When installing such devices, the working condition must be monitored; at the slightest suspicion of defects or breakdowns, they are changed. This type is not suitable for collecting excess pressure; for these purposes you need to buy a safety valve separately.

2. A sophisticated complex for a water heater that combines both functions. It includes a ball valve, safety and shut-off (non-return) valves, and an outlet for draining. The process of monitoring the discharge of excess heated liquid is visual and not automated; the protection efficiency is high. The disadvantage of this group is that water flows onto the floor; to eliminate this problem, it is necessary to equip it with a flexible hose connecting the outlet valve directly to the sewer.

3. Hydraulic safety group, the main difference is the inclusion of a pressure reducer in the water heater piping circuit. The kit also includes: safety and non-return safety valve, siphon. This option is selected for industrial systems, the group is placed on a pipe with cold water. The presence of a siphon allows you to easily drain excess directly into the sewer.

Replacement Guide

The need for this procedure arises when there is physical wear, weakening of the spring, clogging with salt deposits or defective parts. Another reason for the constant leakage of the check valve is related to overpressure in the supply pipe, in this case it is recommended to install a reducer. Leaving a breakdown for a long period of time is fraught with the same consequences as in the absence of a fuse. The replacement process is carried out according to the following scheme:

1. Turn off the power supply to the water heater.

2. Shut off the supply to the device: at the inlet in front of the boiler or common throughout the apartment.

3. Complete emptying of the storage tank.

4. Dismantling (unscrewing) the old safety valve.

5. Installation of a new one, sealing using sealants, flax tow or fum tape. The thread is turned with a wrench 3-4 times.

6. Water supply, checking the tightness of connections.

The correct direction of water is easy to determine: on most devices there is a red arrow, also this information is duplicated in the attached instructions. Before starting installation, it is recommended to check the operation of the unit; when tightening the connection of the relief and check valves, do not press on the threads or apply excessive force. It is easy to check the reliability of a new fuse - fill the water heater tank full and set the maximum temperature (at 30-40 °C the device may not work, especially with small boiler volumes), after a while the discharge begins to drip.

But for complex hydraulic groups, other installation and control schemes apply, in in this case It is important to follow the manufacturer's instructions. For obvious reasons, installing only a check valve in a water heater system is unacceptable (as well as installing heating fittings), the presence of an outlet for releasing excess internal pressure is mandatory.