Greetings, my dear readers! In one of my articles, I described how it works. But there are such devices designed to work with boilers. indirect heating and storage water heaters. I will devote this short post to describing how they work. Let's start by looking at why it is needed.

Why do you need a boiler safety group?

The boiler safety group (abbreviated GBB) is installed instead of the standard safety valve at the entrance cold water... The question arises: "Why change the awl for soap, if there is already a valve?" The point here is that in the event of a thermostat failure, the water inside the water heater or boiler can boil and the pressure will begin to rise very quickly. If you do not drop it abruptly, an explosion will occur. GBB has a higher capacity and will be able to quickly discharge excess water, preventing damage to the container.

In addition, the GBB has a built-in check valve, and many models are also equipped with drain or shut-off ball valves. Let's take a closer look at the construction of a group with an example.

Technical device of the boiler safety group.

On the modern market many manufacturers of fittings for water supply are represented. Each of them tries to attract the buyer with different technical solutions therefore, there is no single GBD design. I'll show you one of possible options from the Italian manufacturer Caleffi:

Explanation of designations in the picture:

1. Cold water inlet - 1/2 or 3/4 inch thread.
2. Check valve- is needed so that hot water is not mixed with cold water through the "back porch".
3. Threaded connection to the boiler.
4. Shut-off ball valve - needed for shut-off.
5. Pressure gauge connection - if you are interested in the inlet water pressure, you can unscrew the plug and put the pressure gauge.
6. Safety valve - discharges water when a threshold value is reached.
7. Manual drain key - when turned, the safety valve opens and water from the container flows into the sewer.
8. 1 inch thread for siphon connection (shown in the figure below).
9. Air intake.

When installing a security group together with a siphon, it becomes possible to make a beautiful, neat drain directly into the sewer. It looks like this:

This is one of the possible design options for GBB, and it is far from the most expensive and complex. For example, German company Stiebel Eltron produces a model called ZH 1, designed for containers from 200 to 1000 liters. It looks rather strange, but it has a large set of necessary functions:

It includes a shut-off valve, a check valve and a safety valve with a drain pipe, as well. The latter is needed in order to remove the influence of external pressure on the water heater. It is made of very high quality, but its price is "cosmic". At the time of writing, it cost 14,000 rubles !!!

There is absolutely simple models, which are essentially an improved version of the standard safety valve for a water heater. Earlier I wrote about why it is leaking and how to deal with it.

For those who still have questions, I am posting a video from Valtec. There, too, everything is easily explained:

Well, now let's move on to the question of choosing this node in the store!

How to choose a safety group for a boiler?

• First, find out what pressure the capacity of your boiler is designed for.... Otherwise, you risk making yourself a flood or explosion at home.
• Thread diameter - if you have a conventional storage water heater, then you need a group with a 1/2 inch diameter. On indirect heating boilers, it will be 3/4.
• The presence of a drain connection - many models of the groups are made with threaded connection for connecting a sewer corrugation or come with a siphon in the kit, as shown in the picture above.
• Additional opportunities - manufacturers like to please customers with all kinds of "buns" such as shut-off valves and pressure gauges.
• Material - GBB should be made of brass. Do not consider other materials.
• The manufacturer is your business. I like more European manufacturers, but even among the "Chinese" there are high-quality specimens.

Morality.

The boiler safety group is expensive, but necessary. In general, you do not need to save on all the things you need for your safety. In this case, spending a few thousand rubles will save you from big trouble, where serious injuries and even death are not excluded. It is necessary to eliminate such a risk (even if it is small). That's all for me, I'm waiting for questions, comments and likes on social networks!

2016-12-25 Evgeny Fomenko

Security kits for different companies

The safety group for the Valliant indirect heating boiler consists of the following parts:

• Check valve.
• Two stopcocks, before and after the check valve.
• Overpressure valve.
• Connection for pressure gauge.
• Drainer.

It is connected to the cold water supply. It is used for indirect heaters of the Vaillant VED H 27/7 INT, VIR 150/5, uniSTOR VIH R 120 type (read how to connect a temperature sensor to a Vaillant boiler). If the water supply pressure is less than 5 bar, use art. -No. 473, if the pressure is more than 5 bar - art. -№474.

If the water is too dirty, a filter must be installed in front of it. For Buderus water heaters, the SG 160S safety group is used, which is usually supplied with the water heater.

It includes a number of details:

• Body with check valves.
• Drain adapter.
• Shut-off and replaceable non-return valve.
• Safety valve.

The body and connections are made of disinfection-resistant brass. Can be installed both horizontally and vertically. When choosing an installation site, you need to leave free access to the units of the device.

It is used with the following models: Buderus Logalux SM-200/5, SU200 / 5, SMH 400/5 W. Watts manufactures fittings and additional devices for boilers and water heaters.

The Watts hardware kit consists of several elements:

• Automatic air vent.
• Pressure gauge.
• Safety valve.
• Shut-off ball valve with 90 degree closing-opening travel.
• Anti-splash water guide.

The units are mounted on a steel console. It is mounted vertically above the boiler. The design is quite compact, made in a brass body. It is recommended to rotate the relief valve knob counterclockwise once a month to flush the relief valve. Withstands water temperatures up to 120 degrees. Suitable for Baxi boilers. It is considered one of the most reliable manufacturers.

The set by Proterm consists of a manometer with an aluminum dial with an operating temperature range of -30 to 120 degrees, an air vent and a safety valve. Shows this pressure in the system and, if necessary, drains excess fluid. When installing, take into account the direction of movement of the water flow, which is shown by the arrow.

The ACV kit, in addition to the safety group, contains a dedicated mixing valve and expansion tank... Suitable for water heaters manufactured by Smart. If you decide to change or adjust something, it is important to remember that the water leaving the device is hot and there is a risk of burns.

The Meibes equipment additionally includes a decorative drain funnel, an 8 bar Meibes ME 6915B.80 PE safety valve and a regulating throttle. Suitable for devices with a volume of up to 200 liters. The installation should be carried out by specialists.

If there are several boilers in the system, OSO equipment will do. Calculated for high blood pressure and having an additional redundant valve.

Appointment

When heated, the water in the indirect heating device expands and puts pressure on the walls of the tank. To prevent destruction and rupture, a safety group is installed. It allows you to control the pressure inside the tank and, if necessary, drain excess water.

When the water pressure reaches a certain limit value, which depends on the settings, the shutter opens and the water is automatically drained, reducing the pressure. It also protects against rupture of the case in case of a breakdown of the temperature sensor and heating the water too much.

If you do not install a security group, in the event of a heater breakdown, the company may refuse you warranty obligations... It is usually supplied with the boiler, but you can also buy it separately. The price for it varies from 700 to 4000 rubles, depending on the parameters of the device and reliability.

Accumulative water heaters of indirect heating are one of the most economical units. The convenience they provide to the owner can hardly be overestimated.

The operation of such a water heater in winter time gives significant savings, because its operation requires a connection to a heating boiler. At the same time, both heat and hot water enter the house. To evaluate the efficiency of a water heater of this type, it is necessary to consider its advantages and disadvantages, as well as study the device of an indirect heating boiler and the principle of its operation.

As already noted, the main advantage of such a device is its high productivity and heating rate. Consider its other benefits:

• The indirect heating water heater works without being connected to the electrical network;
• There is no contact of water with the coolant;
• Possibility of uninterrupted supply of hot water;
• The water heater device allows you to connect multiple sources.

When making a choice in favor of this type of boiler, it should be remembered that, despite its many advantages, the cost of installing an indirect heating water heater is quite high. This is explained by the fact that for its installation it is required to pull a separate pipeline from the boiler and equip it with additional devices.

Like other storage-type water heaters, an indirect heating boiler is, in fact, a large thermos with a heating circuit installed inside. The design of this water heater includes the following elements:

• External casing with fastening elements that allow the device to be installed on the floor or mounted on a wall;
• Internal container (tank);
• Polyurethane foam insulation;
• Thermoelectric sensor or thermostat;
• Security group;
• Air vents;
• Heating circuit;
• Recirculation circuit (installed in some models);
• Tubular electric heater and its piping (in combined models);
• Magnesium anode.
• Supply and discharge branch pipes.

When choosing a boiler for your home, you cannot fail to see the difference in price between models that are very similar in appearance to each other. This is primarily due to the material and manufacturing method of the inner tank, design (floor or wall), the presence of additional circuits and safety devices.

Outer casing

The body of a storage water heater is most often made of steel sheet or durable plastic. In floor-standing models, the design provides for supporting legs, and in wall-mounted models - brackets for mounting the device on the wall. The space between the inner tank and the outer casing is filled with rigid polyurethane foam, which is an excellent thermal insulator. On the outer surface casing, a thermometer is installed to monitor the temperature of the water.

Tank

The internal tank of the water heater makes increased demands on the corrosion resistance of the material from which it is made. In addition, constant temperature drops also set their own conditions. Therefore, when developing boilers, manufacturers Special attention are given to the material of the inner tank. The most persistent option you can read the tank from of stainless steel however, this material significantly increases the cost of the device.

Well proven steel tanks with anti-corrosion glass-porcelain coating. A layer of such material is obtained by spraying and firing at a high temperature. Components included in protective compound, equalize the temperature coefficients of expansion of steel and glass porcelain, which prevents the coating from cracking at temperature extremes.

Coating the inner tank with enamel is typical for inexpensive devices. Accordingly, their service life is the smallest among the entire line of water heaters. Remember this when making your choice.

Heat exchanger

The heating circuit is an optimally shaped spiral made of steel or brass pipe... Such a heat exchanger can be installed both at the bottom of the tank and evenly distributed throughout the entire volume.

Some water heaters are equipped with two heat exchangers - one of them is connected to the boiler, and the second to heat pump or to a geo-collector. This scheme allows you to additionally save energy. Sometimes a cylindrical container installed inside the water heater tank acts as a heat exchanger.

Magnesium anode

A magnesium electrode is used to protect the boiler elements installed in the inner tank. The principle of operation of this element is based on the replacement of electrons participating in ion exchange with their own. This prevents corrosion and rapid wear of the water heater parts. The magnesium anode itself is destroyed and requires periodic replacement.

Delivery and flow tubes

The cold water inlet is located at the bottom of the tank and has a splitter to reduce flow turbulence. This arrangement prevents the mixing of cold and hot water. The tube for taking the heated liquid is installed from the top and has a length that allows the use of the most heated upper layer water. A horizontal indirect heating boiler can have right and left connection of the supply and flow lines. Accordingly, the pipes of the floor boilers are located on the right or left panel.

Protection and control equipment

The boiler heating process is controlled by a thermostat installed in an immersion sleeve that passes through the inner tank and touches the surface of the heat exchanger. This circuit allows the most accurate measurement of the heating temperature.

The safety group is a safety valve that serves to relieve pressure exceeding the maximum value. In models with heating elements, a thermal relay and a thermostat are additionally installed to protect it.

Other structural elements

Some models of boilers are equipped with tubular electric heaters (heating elements) and represent a symbiosis of indirect and direct heating... Such devices are called combined. Installing the heating element allows you to use the combined apparatus in summer time as a conventional electric water heater, which significantly increases the resource of the heating boiler. The popularity of this design is evidenced by numerous reviews of owners who have made their choice in favor of combined floor standing water heaters.

How an indirect water heater works

The principle of operation of the indirect heating boiler is based on the physical phenomenon of heat transfer. The hot coolant from the heating boiler passes along the heating circuit and gives off part of its heat to the water in the internal tank of the water heater. The heat exchange surface in this case is the walls of the circuit tubes. In other words, an analogue of a radiator is installed inside the tank, which heats the water supplied to the floor boiler.

When connecting the boiler, the scheme is followed, according to which cold water flows from below, and hot water is discharged from the upper branch pipe. The heating medium from the boiler must flow from the top and return to the heating system from the bottom. This scheme gives the highest efficiency.

Floor-standing and wall-mounted boilers equipped with a recirculation system allow not to drain part of the water from the "hot" tap, because in the pipeline with hot water there is a constant movement of the heated liquid. For this, a separate circuit is provided with its own pump. The piping of the boiler with a recirculation system allows you to install a heated towel rail on this branch.

Connection diagram

Depending on which boiler the boiler works with, one- or two-circuit, the choice of the scheme for switching it on is carried out.

With three-way valve

The scheme for connecting a combined boiler to a double-circuit boiler necessarily provides for the installation of a three-way valve on the line.

Depending on the signal from the thermostat installed in the floor boiler, this valve opens partially or completely, redirecting the flow of the heating medium from heating system into the heating circuit of the water heater. When heating water to set temperature, the thermostat gives a command to close the three-way valve and the flow of hot heating medium stops.

This scheme has proven itself perfectly when working with wall gas boilers equipped with a circulation pump and a control unit. Such a double-circuit boiler, on a command from the thermostat of a combined boiler, can control a three-way valve, and in the summertime ignite the main burner to heat the coolant.

Video with comments on the installation of an indirect heating boiler, see below:

With two circulation pumps

The connection diagram to a single-circuit boiler requires the installation of an additional pump that supplies the coolant to the heating circuit. In this case, the boiler thermostat controls both circulation pumps... In fact, such a piping assumes the parallel operation of the circuits, although the hot water supply branch has a priority advantage over the heating system.

In the case of connecting a water heater according to a scheme with two pumps, a check valve must be installed in front of each of them to prevent mixing of the heat carrier flows (see the diagram above).

By connecting storage water heater to the heating boiler, the safety condition of its operation must be fulfilled - the temperature of the boiler thermostat activation must be lower than the temperature at which the boiler automation switches off the heating of the coolant.

When installing a boiler in a residential building, great attention must be paid to the safety of its use. It is important to remember that this device contains a significant volume of water with a very high temperature... So that the walls of the boiler are not unduly affected high pressure, as a result of which the heated water will flow out of the device, in such equipment special parts are provided, called a safety group.

Appointment

The main function of the safety group for water heaters is to ensure the required pressure in the system and control it. Thanks to such equipment, it is possible to urgently relieve pressure when it exceeds the maximum allowable parameters.

Compound

The elements of the water heater safety group include:

• Overpressure valve, also called safety valve.
• A non-return valve that prevents water from returning from the boiler to the water supply system.
• Shut-off (shut-off) valve.
• Adapter through which flexible hoses are connected.

These components can be installed separately or presented as assembled in one housing.

In large boilers, a hydraulic accumulator can be installed.

Views

When buying a safety group for a boiler, you can choose among the following options:

• OSO equipment. The OSO KV kit, designed for pressures up to 9 bar, includes a special shut-off valve and a special redundant valve that performs the function of a non-return and safety valve. The OSO BS kit includes a valve that acts as a thermo-mixing and non-return device. Hot water discharged from the branch pipe located at the top of the equipment. Such a safety group can be installed in the case of using several boilers at once.
• Watts equipment. Designed for a pressure of 7 atmospheres, in the complete set has a guide for draining. The advantages of such security groups are high reliability, good quality and affordable cost.
• SYR hardware. Such equipment is designed for a pressure of 6-10 bar, depending on the model. The SYR 330 DN kit is able to withstand temperatures up to + 95 ° C. The SYR 24 DN and SYR 25 DN kits are class 1 acoustic and include a water backflow prevention system, safety valve and shut-off valve, as well as a pressure reducer and an expandable drain. The equipment is made of pressed brass.

• SDM GB kit. This safety group optimally protects closed-loop heaters. Check valve, safety valve and shut-off valve are contained in a single compact body. The kit can be installed on a heater with a volume of 200 to 3000 liters. It is able to effectively protect the boiler against hydraulic overload, maintaining a pressure of 6-10 bar.
• ACV 10800102 kit. Its use speeds up the installation and start-up of the boiler, since this kit contains not only a safety group, but also a special mixing valve, as well as other specialized parts for installing the heater.

Application

The safety valve must be installed on any storage water heater, and if there is no safety group on the device, this immediately voids the device's warranty. When the valve is activated, it causes a small amount of water to be released, which reduces the pressure in the system. Valve response pressure settings are usually fixed and set by the manufacturer. They also have a manual pressure relief option.

Installation and assembly

When choosing a safety group suitable for your boiler, it is important to take into account the pressure for which its safety valve is designed. To effectively protect the apparatus from overfilling with water, the safety group is mounted on the inlet pipe through which cold water is supplied. In this case, the parts should be installed so that the coolant moves in the direction indicated by the arrow on the body of the safety group.

In the following video you can see how to assemble a Vaillant boiler safety valve you just bought from the store.

Safety regulations

• It is important to remember that the parts of the safety group get hot, so there is always a risk of burns on contact with them.
• Regular maintenance of such equipment is recommended, which is carried out in conjunction with the maintenance of the boiler.

Both the installation and maintenance of the security team should be handled by experts.

In the event of an emergency increase in gas or water pressure, a safety group is used to protect the heating system. Anyone who wants to protect their boiler or water heater from premature failure should buy a safety group for heating. It is a combination of three devices - a pressure gauge, a safety valve and an air vent. A pressure gauge is needed to monitor the pressure level in the system - the red arrow indicates a division corresponding to 3 atmospheres as the maximum pressure level. An air vent must be located at the highest point to eliminate excess air in the system. Finally, the function of the safety valve in the safety group is to prevent overpressure in the event that the expansion vessel does not work.

Safety groups for boilers require correct installation, otherwise ill-considered actions will lead to failure of the heating system. The safety group is installed on the supply in such a way that the shut-off valve is behind it. If this closed system heating, it is necessary to arrange the safety group so that if one of the three elements fails, it could be easily replaced.

Boiler safety groups 3/4

Boiler safety group 3/4 made of brass- one of the most common and purchased. In our catalog you will find safety groups with other connection diameters - 1, 1/2. The safety group for the boiler is installed at the cold water inlet in the direction indicated on the body. Any boiler has such a parameter as working pressure, which depends on the pressure in the entire pipeline system. When heated, this pressure can increase by several atmospheres, and excess water will press on the walls of the boiler. The safety group monitors the pressure in the boiler so that it does not rise above the norm.

Buy security group for heating - prices

The price for a safety group for a heating system is quite affordable, and it is also pleasantly combined with the impeccable quality of the product. A compact combination of pressure gauge, safety valve and air vent is available to everyone and is necessary, especially if you use a boiler with a volume of more than 50 liters. To select and buy a safety group for a boiler, contact our specialists at the phone number indicated on the website.

All information on security groups - price, models and much more can also be found on the website.