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Check valve with safety group for boiler. Groups of safety of boilers of indirect heating from various firms. Security kits for different companies

Storage water heaters of indirect heating are one of the most economical units. The convenience they provide to the owner is hard to overestimate.

The operation of such a water heater in winter time gives significant savings, because its operation requires connection to a heating boiler. At the same time, both heat and hot water enter the house. To evaluate the effectiveness of this type of water heater, it is necessary to consider its advantages and disadvantages, as well as to 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 high performance and heating rate. Let's take a look at 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 hot water;
  • The device of the water heater allows you to connect several sources.

When choosing a boiler of this type, it should be remembered that, despite the many advantages, the cost of installing an indirect 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 water heaters, an indirect heating boiler is, in fact, a large thermos, inside of which a heating circuit is installed. The design of this water heater includes the following elements:

  • External casing with fastening elements that allow you to install the device on the floor or mount it on the wall;
  • Internal capacity (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.
  • Inlet and outlet pipes.

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

Outer casing

The body of the storage water heater is most often made of steel sheet or durable plastic. AT floor models the design includes support legs, and in wall-mounted ones - 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 heat insulator. A thermometer is installed on the outer surface of the casing to monitor the temperature of the water.

Tank

The internal tank of the water heater makes high demands on the corrosion resistance of the material from which it is made. In addition, constant temperature changes put forward their own conditions. Therefore, when developing boilers, manufacturers pay special attention to the material of the inner tank. The most durable option can be considered a stainless steel tank, but this material significantly increases the cost of the device.

Steel tanks with anti-corrosion glass-porcelain coating have proven themselves well. A layer of such material is obtained by spraying and firing at high temperature. The components that are included in the protective composition align temperature coefficients expansion of steel and glass porcelain, which does not allow the coating to crack when exposed to temperature changes.

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. Keep this in mind 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 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 geocollector. This scheme allows additional energy savings. Sometimes a cylindrical container installed inside the water heater tank acts as a heat exchanger.

magnesium anode

To protect the elements of the boiler installed in the inner tank, a magnesium electrode is used. The principle of operation of this element is based on the replacement of electrons involved 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.

Feed and flow tubes

Supply pipe cold water located at the bottom of the tank and has a divider to reduce flow turbulence. This scheme prevents mixing of cold and hot water. The heated liquid sampling tube is mounted on top and has a length that allows using the most heated upper layer of water. A horizontal indirect heating boiler can have a right and left connection of the flow and supply lines. Accordingly, the branch pipes of floor boilers are located on the right or left panel.

Protection and control equipment

To control the heating process of the boiler, a thermostat is installed in the immersion sleeve, which passes through the inner tank and touches the surface of the heat exchanger. This scheme allows the most accurate measurement of the heating temperature.

The safety group is a safety valve that serves to relieve pressure in excess of the maximum value. In models with a heating element, 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 (heaters) and are a symbiosis of indirect and indirect water heaters. direct heating. Such devices are called combined. Installing the heater 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 the numerous reviews of the owners who have made their choice in favor of combined floor water heaters.

How an indirect water heater works

The principle of operation of an indirect heating boiler is based on the physical phenomenon of heat transfer. The hot coolant from the heating boiler passes through 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 tubes of the circuit. 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, they adhere to the scheme according to which cold water enters from below, and hot water is discharged from the upper pipe. The heat carrier from the boiler must come from above, and return to the heating system from below. This scheme gives the highest efficiency.

Floor and wall boilers equipped with a recirculation system make it possible 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 fluid. To do this, provide a separate circuit with its own pump. Tying the boiler with a recirculation system allows you to install a heated towel rail on this branch.

Wiring diagram

Depending on which boiler the boiler works with, single- or double-circuit, the choice of the scheme for its inclusion 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 partially or completely opens, redirecting the flow of coolant from heating system to the heating circuit of the water heater. When water is heated to set temperature, the thermostat gives a command to close the three-way valve and the flow of hot coolant stops.


This scheme has proven itself when working with wall gas boilers equipped with circulation pump and control unit. Such a double-circuit boiler, on command from the thermostat of the combined boiler, can control a three-way valve, and in the summer, 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 scheme 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 involves 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 coolant flows (see diagram above).

Connecting storage water heater to the heating boiler, they must comply with the safety condition for its operation - the temperature of the boiler thermostat operation must be lower than the temperature at which the boiler automatics turn off the heating of the coolant.

2016-12-25 Evgeny Fomenko

Security kits for different companies

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

  • Check valve.
  • Two stopcocks, before and after the check valve.
  • Overpressure valve.
  • The union for connection of the manometer.
  • Drainer.

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


If the water is too dirty, you need to install a filter in front of it. Buderus water heaters use the SG 160S safety group, which is usually supplied with the water heater.

It includes a number of details:

  • Body with check valves.
  • Descent switch.
  • Shut-off and replaceable check valve.
  • Safety valve.

The body and connections are made of brass resistant to disinfection. Can be installed both horizontally and vertically. When choosing a mounting location, leave Free access to device nodes.

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


The Watts equipment set consists of several elements:

  • Automatic air vent.
  • Pressure gauge.
  • Safety valve.
  • Shut-off ball valve with 90 degree closing-opening stroke.
  • Water guide to prevent splashing.

The nodes are mounted on a steel console. Mounted in a vertical position above the boiler. The design is quite compact, made in a brass case. Once a month it is recommended to scroll the handle safety valve counterclockwise to flush it. Withstands water temperatures up to 120 degrees. Suitable for Baxi boilers. It is considered one of the most reliable manufacturers.

The Proterm set consists of a manometer with an aluminum dial with a range operating temperature from -30 to 120 degrees, air vent and safety valve. Displays the current pressure in the system and drains if necessary excess liquid. When installing, you should 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 specialized mixing valve and expansion tank. Suitable for smart water heaters. If you decide to replace or adjust something, it is important to remember that the water exiting the device is hot and there is a risk of burns.

Meibes equipment additionally includes a decorative drain funnel, safety valve Meibes ME 6915B.80 PE 8 bar and control throttle. Suitable for devices up to 200 liters. Installation must be carried out by specialists.

If several boilers are combined in the system, OSO equipment is suitable. Designed for high blood pressure and having an additional backup valve.

Purpose

When heated, the water in the indirect heating device expands and exerts pressure on the walls of the tank. To prevent destruction and rupture, a security group is established. 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 lock opens and the water drains automatically, reducing the pressure. It is also a protection against rupture of the case when the temperature sensor breaks and the water is heated too much.

If you do not install a safety group, in the event of a heater breakdown, the company may deny you warranty. It usually comes 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.

Indirect heating boiler It is designed to provide a private house, dacha, enterprises with enough water. The principle of operation of the boiler is simple, however, the efficiency of this device depends on how correctly the indirect heating boiler is connected to the boiler.

An indirect heating boiler is purchased to work with a single-circuit boiler. Together, this equipment will take up more space than a double-circuit boiler. In families with a household of two or more people, flow heating systems will be ineffective, optimal solution— indirect boiler heating.

The capacity of boilers varies from 80 liters to several cubic meters. There are recommendations for selection of boiler capacity . For two people, this is the minimum tank that can serve two points of water intake at the same time. Three people need a 100-liter tank for three points of water intake. For four - it's 120 liters, and for five - 150 liters, etc. If the house is often washed in the bath, then a tank with a capacity of 120 liters is purchased. Please note that these figures are averages, as the need for hot water is very individual.

Boiler internals indirect heating is quite simple - service water heated by the coolant from the heating system passing through in a hot water tank.

It is preferable to purchase boilers with a stainless steel tank (for durability). Some characteristics are shown in the table below:

where, d is the difference between the inlet and the reached temperature. These characteristics can only be achieved if the input power of the boiler is not less than the specified power of the boiler heat exchanger! It should also be noted that the temperature of the incoming water in winter and summer will be different (from +5C to +15C).

There are also boilers with a system that have a self-cleaning function from scale. It is provided by the shape of the internal tank in the form of a corrugation.

The characteristics of such boilers are shown in the following table:

As already mentioned above, the output characteristics directly depend on the power of the boiler itself. Thermal power the boiler should not be lower than the capacity of the boiler, otherwise the amount of heated water will be less than declared. And if the power of the boiler exceeds the power of the boiler, then the amount of heated water will be the maximum possible, based on the power of the boiler itself. For example, if you purchased a 31 kW boiler and you need a 100 liter boiler, then the best purchase in this case would be a boiler with a coil, because the capacities of these units are ideally matched for best performance - 30 and 31. A boiler with a “tank in tank "23 kW will not be able to master the full power of the boiler and the characteristics given out by it will be less than in the first case. If you bought a 24 kW boiler, then in this case it is better to take a boiler with a tank-in-tank system, since in this case the maximum DHW performance is achieved, and the boiler with a coil will have power losses.

Most engineers consider that tank-in-tank boilers are preferable. Due to self-cleaning, durability is achieved, and due to internal device the heat transfer area is increased, which results in increased productivity. Therefore, in most cases, such boilers are preferable. Although simple ones are considered cheaper in cost. And in general, if you have chosen a simple boiler - this is not bad at all.

The following diagram shows an example location stop valves and protection devices connecting an indirect heating boiler to a floor-standing boiler adapted for its connection - with the ability to control pumps. Basically, these are volatile boilers of foreign production.

When an indirect heating boiler is connected to a non-volatile boiler, such as domestic AOGV or KSG, the boiler pump is controlled from the boiler thermostat. At the same time, it should be noted that the water heating rate is significantly reduced, since the boiler power is distributed between the heating circuit and the boiler.

Before the boiler at the cold water inlet, it is obligatory to install safety relief valve by 6 - 8 bar, depending on the characteristics of the boiler (example in the photo below. Here is a relief valve with a check valve assembly).

Boiler safety group Watts 3/4 for 7 bar (10004611)

Everyone knows that when you turn on hot water, for some time it comes out of the tap cold. This problem is solved by installing groups without boiler safety with an additional weak pump. Many manufacturers offer such pumps. The following diagram shows an example of installing a recirculation line:

Please note that the above diagram is applicable to boilers equipped with a recirculation outlet. If there is no such output, then the scheme will look like this:

Here we see the recirculation line cutting into cold water after the check valve and safety group. On it, after the pump, another check valve crashes to prevent cold water from entering the recirculation.

In general, when connecting an indirect heating boiler for hot water supply in the house, we will get the same comfort as in a city apartment with central water supply with an advantageous difference in its cleanliness. Such water can be used for food purposes, even poured into a kettle without harm to health.

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 heating safety group. It is a combination of three devices - a pressure gauge, a safety valve and an air vent. A pressure gauge is needed to control the level of pressure in the system - the red arrow indicates the division corresponding to 3 atmospheres as the maximum pressure level. An air vent should be located at the highest point, which eliminates excess air in the system. Finally, the function of the safety valve in the safety group is to prevent excessive pressure in case the expansion tank does not work.

Boiler safety groups require correct installation otherwise, ill-conceived 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 located 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 can be easily replaced.

Boiler safety groups 3/4

Boiler safety group 3/4 made of brass- one of the most common and bought. 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 operating 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 controls the pressure in the boiler so that it does not rise above normal.

Buy a safety group for heating - prices

The price for the security group for the heating system is quite affordable, and it is also pleasantly combined with the impeccable quality of the goods. The 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 the 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 site.