Safety valve in heating, installation, operation, designs

Overheating of the coolant leads to its strong expansion, especially if the temperature has reached the boiling point. When the coolant expands, the pressure in the system rises, which can lead to serious consequences: from slight leakage of connections or failure of heating system components, to rupture of lines in inaccessible places (walls or under floor screed).

A well-known way to prevent the destruction of a heating system due to high pressure is a safety relief valve. In the article we will look in detail at its design and operating principle, define the criteria for choosing a mechanism, the installation algorithm in the heating system, as well as actions in a situation if the pressure relief valve has leaked.

Purpose and installation location

Closed heating systems operate under a certain pressure.
A significant increase in operating pressure leads to equipment failure. Connections may leak, plastic parts and elements may burst. In the most unfavorable situations, the boiler heat exchanger may explode. This is already very dangerous and threatens not only the floor flooded with hot coolant, but also burns. After all, the temperature is serious. The overpressure relief valve must protect the heating system from excessively high pressure. As long as the system parameters are within normal limits, it does not manifest itself in any way. Although the pressure in the system gradually increases from the moment the boiler starts, the expansion tank compensates for it, maintaining a stable state of the system. But it may not do this indefinitely, although, with proper calculation, it is enough for standard situations. If the expander fails to cope with the task, the pressure begins to rise. When it exceeds the threshold, the excess pressure relief valve is activated. It simply releases part of the coolant, thereby stabilizing the emergency situation.

That is, the excess pressure relief valve in the heating system works in emergency situations. That is why it is also called “emergency”. And also “discharge”, “drain”, “protective” and “explosive”. All these are names of the same device.

What does a safety (emergency) valve for heating look like?

As is clear from the description, when the pressure increases above a certain limit, a certain amount of coolant is simply released from the system. If you came to the boiler room and a puddle formed under the emergency valve, it means there was an emergency situation during which the pressure increased. No other alarm

So these traces are worth paying attention to. It is worth immediately checking the functionality of the valve itself and the membrane tank

Most likely, they are the reason. If you do not pay attention to these symptoms, after a while you may encounter problems: either something will “fly” in the system, or the water heating boiler will rupture.

Installation location of the emergency heating valve - on the supply pipeline, near the boiler

Of all the equipment in an individual heating system, the most dangerous is the boiler. Therefore, the excess pressure relief valve is installed either directly on the boiler itself (if there is an appropriate outlet for installation) or on the supply line immediately after the boiler. The distance is small - 20-30 cm from the body. If the boiler does not have this type of fittings (indicated in the description), then it is installed in the so-called safety group or placed separately. The safety group is placed at the outlet from the supply line immediately after the boiler (before the first branch and any other device), on which a pressure gauge, automatic air vent and excess pressure relief valve are installed.

Operating principle

Most ordinary users faced with closed water heating systems are familiar with only one type of safety valve - a simple spring valve with a fixed setting, shown in the photo. The reason is clear - these products are universally installed on any boilers, since they are part of the safety group along with a pressure gauge and an air vent.

Note. Wall-mounted heat generators operating on electricity and natural gas are equipped with safety elements from the factory. They are placed inside the case and are not visible from the outside.

Let's understand how a regular emergency valve works, shown in the diagram above:

1. Under normal conditions, the diaphragm, attached to the stem and supported by a spring, sits tightly in the seat and seals the passage.
2. If the coolant overheats, it expands and creates excess pressure in a closed system, partially compensated by the expansion tank.
3. When the amount of water pressure reaches the valve response threshold (usually 3 Bar), the spring is compressed under its influence and the membrane opens the passage. The boiling coolant is automatically discharged until the spring has enough strength to close the flow area again.
4. In the event of an emergency, the owner of the house can relieve excess pressure himself by turning the handle at the top of the product.

A few words about where the relief valve is installed along with the safety group in a closed heating system. Its place is on the supply line in the immediate vicinity of the boiler (recommended no further than 0.5 m).

Important point. It is prohibited to install taps, valves and other shut-off devices on the pipeline leading from the heat generator to the safety elements.

You should not tightly connect the pipe of the product to the sewer - wet spots or puddles will indicate the valve has been activated and problems in the heating network. For example, the expansion tank failed or the circulation pump malfunctioned when working with a solid fuel boiler (the electricity may have been turned off). Often the device begins to leak due to debris getting between the seat and the plate. More about his work is described in the video:

Additional information. Masters and installers call spring relief valves blasting valves because the pressure of the coolant compresses the spring and causes the membrane to explode. Do not confuse them with explosive elements installed on the chimneys of industrial boiler houses that burn natural gas.

Manufacturers

The greatest demand is for security groups from Valtec and Watts. Their products are distinguished by high quality workmanship and reliability. For example, VT.460.0.0 from Valtec is used for heating systems with a nominal pressure of up to 10 bar. The maximum temperature of use should not exceed +120°C. Steam, water or a special liquid can be used as a coolant.

The emergency valve has a fixed setting of 3 bar. The body of the safety group is brass, nickel plated. The thread for connection is internal, size 1″. The cost of the VT.460.0.0 group starts from 1,700 rubles.

Security Groups from Watts

The WattsKSG-MS security group has similar characteristics. The body is made of brass, but unlike the previous device, it is located in a heat-insulating casing. The emergency valve response threshold is 3 bar.

When installing the safety group and other parts of the heating system, you must strictly follow the instructions supplied with them from the manufacturer. Because if installed incorrectly, the system will not work properly, or an error made during installation will lead to its breakdown.

Price

The price of the mechanism depends on its type, characteristics, materials and workmanship, quality of processing and manufacturer's markup.

InstructionsBoiler room equipmentSafety fittings

Recommendations for selection and installation

Since not all manufacturers of heating equipment complete their products with a safety group, you often have to make the choice of a safety valve for the heating system yourself. To do this, it is necessary to study the technical characteristics of the boiler installation, namely, know its thermal power and maximum coolant pressure.

For reference. Most solid fuel heat generators of well-known brands have a maximum pressure of 3 Bar. An exception is STROPUVA long-burning boilers, whose limit is 2 Bar.

The best option is to purchase a valve with pressure control that covers a certain range. The regulation limits must include the value for your boiler. Then you need to select a product according to the power of the thermal installation, but it’s difficult to make a mistake here. The manufacturer's instructions always indicate the limits of the thermal power of the units with which a valve of a particular diameter can operate.

It is strictly forbidden to install shut-off valves on the section of the pipeline from the boiler to the place where the excess pressure relief valve is installed. In addition, you cannot install the device after the circulation pump; do not forget that the latter is not able to pump the steam-water mixture.

To prevent splashing of water throughout the furnace room, it is recommended to attach a tube to the outlet of the valve that drains the discharge into the sewer. If you want to visually control the process, then you can place a special drain funnel on the vertical section of the tube with a visible break in the stream.

Types of valves

Under the influence of the pressure of the superheated coolant, the membrane rises and is discharged into the drain.
The following types of mechanisms are suitable for installation in a heating system:

Discharge

A relief valve for heating operates according to the principle of the simplest protective device: the resulting gases or coolant, after reaching the excess pressure limit, press on the membrane and leave the system.

Lever-load

Suitable for pipes with a diameter of 0.2 m and larger. In heating systems in which the heat source is a boiler, lever-load type valves are not installed. In these mechanisms, a load is used to increase the effect on the membrane. In order to determine the pressure force at which the valve is activated, adjustment is carried out by changing the mass of the load.

Back

An emergency device of this type is installed to relieve excessive pressure. Additionally, it allows the coolant to move through the pipes in only one flow, determined by the design.

Spring

In a ball valve design, the excess pressure depends on the weight and size of the ball

The most popular device is used for an autonomous heating system. The device is durable and has a simple design: the rod is pressed by a spring. It is possible to configure the device’s response parameters using the existing control mechanism. The force of impact is determined by the degree of compression.

Ball

It has a very simple design: the hole is closed with an ordinary steel ball (by weight). The valve response pressure is pre-calculated; it directly depends on the diameter of the hole and the weight of the ball.

Air

The purpose of such a valve is to free the system from the resulting gases that create plugs and prevent the heating from working properly.

Connection type

Based on the type of connection or connection to the pipeline, valves are divided into:

• flanged products - equipped with flange plates at each outlet and connected to mating flanges at the ends of the pipes using bolts;
• threaded - imply the presence of outlet pipes with external threads;
• welded - attached to the gas pipeline by welding and ensure 100% tightness.

The main thing in a moonshine still is safety.

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Home brewing is gaining more and more fans. The number of amateurs and professionals is growing. But you shouldn’t lose sight of the safety of making moonshine. The pressure relief valve is designed to do just that. After all, there are enough cases when moonshine stills exploded in apartments of residential buildings. And this happens not only because of inexperience and irresponsibility, but also because of homemade low-quality devices.

The pressure relief valve prevents mechanical damage to the unit due to excess pressure. This happens by releasing excess gas. This happens automatically. In this case, the emission of steam stops when the working medium reaches an operating state.

Excess steam can occur not only due to improper operation. For example, the use of additional heat sources, incorrect assembly of the unit. Even if properly assembled and used, the operating environment may increase.

Operating principle

The pressure relief valve consists of the required components: a shut-off element and a set point. Last

Sectional Pressure Safety Valve

provides force on the sensitive element. The components for the closure body are a seat and a bolt. The simplest example for a valve is a spool.

In the simplest case, the set point can be a spring. With its help, it is configured in a certain way. The force on the spool must be such that the working medium does not pass through the seat. The adjuster is adjusted using a special screw.

When the pressure relief valve is closed, two forces act on it:

1. the operating environment of the system it protects. Relatively speaking, this force is trying to open it.
2. A master that prevents this opening.

When the force from the working environment increases, the spool is pressed against the seat with less force. At some point it will become zero. And that’s when the locking mechanism will begin to open. If the first force continues to increase, the relief valve will operate and the working medium will be discharged through it.

After the decrease, the power of the set point increases again. The safety relief valve closes.

Homemade or purchased devices?

Someone remembers the times when moonshine brewing equipment was made from scrap materials. And everything was made by hand or repurposed from something. Even a pressure relief valve. Today the situation has changed. Moonshine units can be purchased ready-made. So what to choose: a ready-made device or a homemade one?

If we talk about efficiency, then it will be cheaper to make it yourself. Although some parts, such as a safety relief valve or a thermometer, will have to be purchased. Well, as for safety, it’s clear: a ready-made unit produced at the factory.

The moonshine stills on the market are of very good quality. They are collapsible, so they are easy to wash. And also quite convenient to store.

But the most important thing is that their safety is given great attention. All models have a safety relief valve, which eliminates the risk of explosion

Such additional devices of a moonshine still as automatic controllers, a thermometer and a pressure relief valve make the process of preparing homemade strong alcohol absolutely safe. Their presence in the device is mandatory. It is thanks to them that control over each stage of preparation is maximum, and risks are minimal.

What can happen if there is no boiler protection

A more critical situation may arise when the water pressure of the water supply network drops sharply. This usually happens at night, when the relevant services carry out unforeseen repair or maintenance work, turning off the cold water supply. In this case, completely draining the water from the boiler leads to burnout of the heating element.

To avoid such situations, many “woe Kulibins,” not realizing the complexity of the situation, install conventional check valves in the water heater installation system. However, they do not understand that they are planting a “time bomb” in their home.

After all, a water heater is a complex heating device; its automation and thermostat can also fail at the most inopportune moment. Then events can turn out very sadly. If the material from which the water heater tank is made is chosen correctly, then boiling does not occur there, since the boiling point here moves above the usual 100 degrees and the situation is kept under control. However, if the material does not meet the strength characteristics, then if any water tap in the apartment is accidentally opened, the internal pressure of the tank may drop sharply, the boiling point of water will return to 100 degrees, and then an avalanche-like flow of steam will occur at lightning speed, which can lead to mechanical damage to the boundaries of the tank and powerful explosion.

Conclusion

When making a conclusion regarding the installation of additional protection for the water heater, it is necessary to take into account the following factors:

• Discharge excess water when it is heated, maintaining the parameters of its safe pressure zone;
• Do not allow water to flow back from the heater;
• Smooth out water hammer and pressure surges in the water supply system.

Types of security groups and the principle of choosing the appropriate model

A standard safety valve for a boiler may differ in design in several design features. These nuances do not change the functionality of the device, but only simplify use and maintenance. To choose the right safety unit, you need to know what safety valves for boilers are and how they differ.

Lever models

The most common type of standard safety assembly is the lever model. This mechanism can be activated manually, which is convenient when checking or draining water from the boiler tank. They do it like this:

• A horizontally located lever is installed vertically;
• direct connection to the stem activates the spring mechanism;
• the safety valve plate forcibly opens the hole and water begins to flow from the fitting.

Even if the tank is not completely emptied, a control drain is performed monthly to check the functionality of the safety unit.

The products differ in the design of the lever and the fitting for discharging water. If possible, it is better to choose a model with a flag fixed to the body. The fastening is made with a bolt that prevents children from manually opening the lever. The product has a convenient herringbone-shaped fitting with three threads, which ensures reliable fixation of the hose.

The cheaper model does not have a flag lock. You can accidentally catch the lever with your hand and unnecessary drainage of water will begin. The fitting is short, with only one threading ring. It is inconvenient to fix the hose onto such a protrusion and can tear it off under strong pressure.

Models without lever

Safety valves without a lever are the cheapest and most inconvenient option. Such models often come complete with a water heater. Experienced plumbers simply throw them away. The units operate similarly to lever models, but there is no way to manually perform a control drain or empty the boiler tank.

Models without a lever come in two versions: with a cover at the end of the body and blind. The first option is more convenient. If clogged, the cover can be unscrewed to clean the mechanism. A blind model cannot be tested for functionality and cannot be descaled. The fluid discharge fittings for both valves are short with one threaded ring.

Safety components for large water heaters

Water heaters with a storage tank volume of 100 liters or more are equipped with improved safety valves. They work in a similar way, only they are additionally equipped with a ball valve for forced drainage, as well as a pressure gauge.

Particular attention should be paid to the fluid drainage fitting. It's threaded

Reliable fastening prevents the hose from being torn off by strong pressure and eliminates the inconvenient use of the clamp.

Original models

For lovers of aesthetics and comfort, manufacturers offer original safety components. The product is equipped with a pressure gauge, chrome plated, and given an elegant shape. The products look beautiful, but their cost is high.

Difference in body markings

High-quality products must be marked on the body. The manufacturer indicates the maximum permissible pressure, as well as the direction of water movement. The second marking is an arrow. It helps to determine which side to place the part on the boiler pipe.

On cheap Chinese models there are often no markings. You can figure out the direction of the liquid without an arrow. The check valve plate must open upward in relation to the boiler pipe so that water from the water supply flows into the tank. But it’s impossible to determine the permissible pressure without markings. If the indicator does not match, the safety unit will constantly leak or will not work at all in an emergency.

Other types of valves

When they try to save money on a safety group, they try to install a blast valve designed for the heating system on the water heater. The nodes are similar in functionality, but there is one nuance. The blast valve is not capable of releasing liquid little by little. The mechanism will work when the excess pressure reaches a critical point. The blast valve can only release all the water from the tank in the event of an accident.

Separately, it is worth considering installing only a check valve. The mechanism of this unit, on the contrary, locks the water inside the tank, preventing it from draining into the pipeline. If there is excess pressure, the working plate with the rod is not able to work in the opposite direction, which will lead to rupture of the tank.

Types of safety valves

These protection elements are classified in different ways.

Spring ones are the most common, used for small boiler rooms. They have a simple and reliable design and the ability to easily adjust the operating pressure in the system. Also, one of the advantages is the low cost. Lever safety devices are not particularly popular, because, basically, the model range is represented by diameters from 50 mm. They are used in the industrial sector. Pulse devices are used on steam boilers with pressures greater than 39 kgf/sq.cm (3.9 MPa). At least 2 pieces are installed on each boiler. (control and working). Low-lift ones have a valve lift height of 5% of the seat diameter, therefore they have a low throughput. The advantages include: simple design, affordable price.

Low lift and full lift

In full-lift valves, the bolt rises to a height of at least 25% of the seat diameter. They are classified as two-stage. They are characterized by high throughput, high cost and complex design.

Full-lift safety devices have a bell. Its job is to help the bolt achieve full lift. Full lifts are used mainly in systems in which the medium is compressed. Proportional ones open the valve in proportion to the increase in pressure and the volume of the discharged medium increases proportionally with the rise of the valve. These protective devices are used for water and other liquid media.

The advantages of using a proportional valve include:

• opening the shutter according to need;
• lightweight design;
• low cost;
• vibrations occur automatically.

The disadvantage of two-stage devices is self-oscillation of the shutter. The reason for this is exceeding the standard size or variable emergency flow of the medium.

Pressure regulator

The operation of the batteries and the pump is disrupted due to high or low pressure levels. Correct control of the heating system will help to avoid this negative factor. The pressure in the system plays a significant role, it ensures that water gets into the pipes and radiators. Heat loss will be reduced if the pressure is standard and maintained. This is where water pressure regulators come to the rescue. Their mission is primarily to protect the system from too much pressure. The operating principle of this device is based on the fact that the heating system valve located in the regulator works as a force equalizer. Depending on the type of pressure, regulators are classified into: statistical, dynamic. It is necessary to select a pressure regulator based on throughput. This is the ability to pass the required volume of coolant, in the presence of the required constant pressure drop.

Reasons for valve operation

After several emergency operations, the valve needs to be replaced due to the weakness of the spring.
A working safety device will never operate without a reason. Each valve actuation must be examined to determine the trigger. There may be several of them. Although they are not always serious, everyone should be checked.

• Unstable operation or failure of the heating boiler thermoregulation system. Triggers are usually frequent and water spills are abundant.
• Problems with the expansion tank. This may be the initial setup. Hidden reasons: nipple malfunction, membrane failure. In such cases, sudden pressure surges occur in the system, which leads to short and frequent valve openings.
• Limit value of pressure in the heating system. The protection mechanism leaks slightly. Such manifestations are present because the accuracy of the spring device is ±20%. To avoid such situations, you should more accurately configure the system and select the appropriate equipment.
• Valve wear. After several trips, the performance of the protective device decreases. Therefore, it is better to replace it with a new one or repair it.
• Malfunction of the spring. This happens over time, even in the absence of triggers. Sometimes drips appear as a result of coolant leaking around the rod. Under such circumstances, repair or replacement cannot be avoided either.

You can check the serviceability of the safety valve using the red handle. If you turn it in a clockwise direction, water should appear on the normal valve. The leak stops immediately after the handle stops rotating. If this does not happen, you need to twist it again. When this does not help, the protective device will need to be replaced.

How to check serviceability

You can check the serviceability by turning on the water heater (do not open the hot water tap) and wait until the water is completely heated to the maximum possible temperature. After a while, excess water should drip from the safety mechanism.

The valve will not work if:

• the hot water tap is faulty (pressure will be released through it);
• the thermostat is set to 30-40⁰ C (the water will not warm up to such an extent that the pressure inside the tank reaches the permissible level);
• the operating pressure of the safety valve device is high and does not correspond to the productive capacity of the water heating equipment (the maximum permissible pressure in the storage tank will not be sufficient for the safety valve mechanism to operate. It may have dangerous consequences).

Water from the valve device must be drained periodically. If this does not happen and all of the above cases are excluded, the fuse itself is faulty. It needs to be replaced with a new one, having first checked its performance.

A safety mechanism must be installed on water heating equipment to ensure long, uninterrupted, safe operation of the device. You should choose the option that is most suitable in terms of all design and functional parameters, otherwise its operation will be ineffective and even dangerous. In this case, it is necessary to periodically check its serviceability, approximately once a month. If a malfunction is detected, the inoperative valve must be replaced with a new one.

It is very dangerous to improve it independently, replacing it with a check valve mechanism. This will lead to unpleasant consequences, due to which it is likely that you will have to replace the purchased water heater with a new one.

Installation rules, replacement frequency

An emergency valve is always installed on the supply side, after the boiler. In this case, the following rules are observed:

• If the relief valve is installed separately, a pressure gauge is placed in front of it to monitor the condition of the system.
• Placed at a distance of 20-30 cm from the boiler.
• The outlet is made with a pipe of the same diameter as the supply pipeline. To determine the pressure as accurately as possible, it may have a slight slope towards the boiler.
• Shut-off devices (taps, check valves, etc.) must not be installed between the boiler and the blast valve.
• In systems with natural circulation, this device is placed at the highest point of the system.

Placed close to the boiler (in many models it is located in the boiler itself, in some boilers there is space for installation)

To prevent the discharged coolant from leaking onto the floor, you can put a hose on the outlet pipe. It can be placed in a container or discharged into the sewer. But in this case, it is necessary to somehow monitor the operation - set an alarm. After all, he doesn’t just play off, but for some reason.

Another important point: after several operations (5-6), the excess pressure relief valve must be replaced. This is due to spring wear. The device starts to work incorrectly. The valve costs a little, so it’s not expensive. The only unpleasant point is that locking devices cannot be placed in front of it. Therefore, the emergency valve can only be removed by completely stopping the system and reducing the pressure to atmospheric pressure. That's the rub.

Where to install the overpressure relief valve

The situation can be improved if shut-off valves are placed after the demolition man. In this case, at least you won’t have to drain the coolant from the system, but only from the boiler, which is not so scary.

What is it needed for?

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. Both ends of the body have pipe threads ranging in size from 1⁄2" to 3⁄4" depending on the type of product.

Purpose of the gas valve

PSK is a safety valve element responsible for the safety of the gas pipeline and gas equipment connected to it. During operation, the valve is in a closed position, therefore it is classified as a closed pipe fitting.

Such devices are installed not only on gas pipelines, they are an integral part of other communications - water supply, heating networks. Everywhere they perform the same function - they stabilize the pressure in the network, provide the operating parameters necessary for the proper functioning of the system.

The valve serves to relieve excess gas if pressure parameters become critical. Fuel that creates an imbalance in the system is discharged into an auxiliary pipeline or discharged into the atmosphere

The pressure surge is usually short-lived and depends on a number of factors.

Reasons that can cause excess pressure in the system:

• breakdown of connected gas equipment - double-circuit boiler, instantaneous water heater or capacitive boiler, shut-off valves;
• use of fuel of inappropriate composition;
• change in temperature indicators in the pipeline;
• failure in the thermal-mechanical circuit.

The installation location of the gas safety valve is standard, depending on the efficiency of the application: either in the pressure regulator, or immediately behind it. After automatic operation of the valve, it returns to its operating – closed state.

In a gas network, the valve is a separate device or integrated into the pressure regulator. It is triggered if the operating gas pressure exceeds the nominal level by 15%

What are the consequences of the absence of a PSK on the network? The most common consequences are mechanical destruction of the pipeline or breakdown of connected equipment, which can cause a gas leak.

There is also a possibility of an explosion, so it is necessary to constantly monitor the serviceability of the device, carry out timely maintenance and replace failed elements

Along with relief devices, gas safety shut-off valves are also used, with the help of which the fuel supply is shut off. This happens automatically. The shut-off valve element is installed on the pipeline, in the gap between the filter and the pressure regulator.

The operating limit of the SPD is indicated in the technical data sheet of the device. The upper critical parameter is usually equal to the formula: slave. pressure +25%.

Professional installation advice

Even such a simple procedure as installing shut-off valves is based on the implementation of certain rules. For example, the design of a room often requires camouflage of the pipeline and security group.

You can hide devices, but subject to three conditions:

• the length of the flexible line or pipe from the fuse to the tank should not exceed 2 m, otherwise there will be excessive additional pressure on the valve spring;
• the ideal installation of the fuse is directly to the boiler fitting, and if this does not work, then installing a tee is still excluded;
• To service the fittings, a technical hatch should be equipped.

Many people worry when they see drops of water on the valve connection. This is a normal phenomenon and indicates that the device is working properly.

From time to time, small pressure surges occur in the line, which provoke a minimal discharge of liquid. You need to worry when water either does not appear at all or pours continuously.

The line length between the water heater and the fuse should be minimal. This is necessary not for aesthetic reasons, but so as not to create additional pressure in the pipes

It should be remembered that independent modernization of safety devices is strictly prohibited. If you need a 0.8 MPa valve, then you need to purchase just such a new product, and not try to somehow remake or adjust the 0.7 MPa device.

If there is any doubt about the functionality of the safety valve, you should dismantle it and check whether the spring or seal is clogged. Are you having problems with your water heater itself and don’t know what to do? We recommend that you familiarize yourself with common boiler breakdowns and repairs. If you lack skills, invite a specialist from the service center.

Expert advice

• A blasting device with standard technical characteristics allows water to pass through even at low pressure levels when clogged. The problem can be solved by cleaning the body parts. To do this, the product must be dismantled and placed in a container with vinegar for 2 - 3 hours. Then rinse it with water until completely clean and install it in its original place, lubricating the connection area with alcohol.
• If the valve continues to leak even after cleaning, then most likely the rubber gasket resting on the seat is clogged with debris. It is easier to replace such a part than to clean it without deformation. Replacing the valve on the supply pipeline to the boiler can be seen in the video:

• A number of consumers quite reasonably doubt the durability of shut-off valves with plastic parts. They actually have a shorter service life, so it’s better to immediately buy ones with metal components. Such products are on average 100 - 150 rubles more expensive, but they last much longer.
• You cannot simply turn off the device, even if it is leaking. A huge number of heating boilers have failed precisely after installing the plug.

Safety valve

The name of the device speaks for itself. Its main function is to relieve unexpected loads that may arise under certain circumstances. Plus additionally adjustable coolant flow.

By the way, it can be installed on any section of the pipeline

In this case, it is not the location that is important, but the ease of maintenance if such a need suddenly arises

Types of safety valves

• The simplest option is clutch fuses made of brass. Their design is simple - threads are cut on both sides, and the valve is a spring-loaded rod with an EPDM gasket. This is a direct-flow model, the valve of which opens under the pressure of the coolant flow. Back pressure is blocking the line. This is one of the cheapest devices, but it lasts a very long time, which is time-tested.
• There is another brass option, but with a more complex design, where the pipes are connected in perpendicular planes. It uses a stainless steel rod and spring. Install it directly after the circulation pump. The operating principle of such a device is quite simple. The coolant pressure compresses the spring, which begins to put pressure on the rod. It opens a channel through which the coolant is squeezed out of the system, saving it from ruptures of pipes and other elements. By the way, the maximum temperature that the valve can withstand is 120C.
• There are a large number of varieties of check valves, which are also included in the safety group. Their main function is to prevent a counterflow of coolant from occurring if the pressure in the system suddenly drops.

There are several main types - disk, ball, flag and others. But they are all divided into spring-loaded and springless. With the first, everything is clear - there the main emphasis is on the counterforce of the spring. The second type is when the locking element returns under the influence of its own mass.

Three way valves. This type of shut-off valve is installed in heating systems where low-temperature circuits are provided. For example, when the circuit has a condensing boiler. Currently, manufacturers produce this type of valve with manual switching or electric switching. In the second case, it is necessary to connect the device to an alternating current network with a voltage of 220 volts.