The operation of heating units is associated with increased pressure and intense vaporization. Maintaining these indicators within acceptable limits is the key to the safe operation of any sample of boiler equipment. For these purposes, the heating network has a special set of protective and monitoring devices, including pressure sensors and safety valves.
What is a security group
A safety block for heating systems is a special set of 3 devices installed in a specific place in a common collector. Its main purpose is to protect heating networks in the event of emergency situations (emergency modes). In addition, with their help, the user will be able to monitor the current state of the entire system as a whole, including the process of heating the coolant. Their implementation in the form of a single module makes it easier to install in an existing heating network.
The considered control and safety unit consists of 3 different devices, united in a common cast case of the collector type. It is usually made of brass or stainless steel and has 3 seats, made in the form of standard threaded connections. In its lower part there is a special coupling that allows the module to be connected to the heating system. Control and safety devices are located on top:
- a typical pressure gauge for measuring the pressure of the carrier;
- automatic air venting device;
- dump or safety valve.
Thus, the safety group for heating combines 3 functions at once, which should be dealt with in more detail.
Assigning group elements
When considering the individual elements of the safety unit, special attention is paid to their purpose:
- the pressure gauge is designed to control the water pressure in the boiler tank, as well as in the entire system as a whole; its other purpose is to monitor the pressure of the coolant when filling pipelines in closed-type units;
- a device for bleeding off excess air allows you to get rid of the so-called "jams" when setting up a heating network; also with its help portions of steam are released, formed in the boiler tank during overheating;
- the safety valve is designed to relieve the pressure of water, steam or their mixture when they exceed a predetermined threshold level.
The principle of operation of the heating system safety group is to continuously monitor its state and prevent emergencies. They mean the boiling of the coolant constantly circulating in the water jacket of the boiler and an excessive increase in pressure in the system, despite the presence of an expansion tank in it.
At the initial stage of deviation from the norm, the pressure gauge registers a noticeable increase in this indicator, after which the excess air is discharged through the bleed device. At the last stage, water (steam-water mixture) is discharged by means of a safety valve. In the absence of a boiler safety group, following overheating of the system, an explosion of the shell of the unit is possible with all the ensuing consequences.If present, the module operates in automatic mode, when the relief valve will release steam until the pressure inside the enclosure returns to normal. In most boiler equipment samples, the upper threshold is about 3 bar. However, models with a maximum working pressure of the order of 1.6-2.0 bar are often found.
When you can do without GB
A safety group for heating a house is not needed in all situations, since most samples of equipment of the corresponding type already have protection elements. However, at the request of its owner, the installation rules allow for the possibility of installing the node as a safety net.
Heat generators using natural gas, diesel fuel or electricity are characterized by a high level of safety. Their built-in safety means are sufficient to stop the heating of the coolant when an increase in temperature or pressure is detected.
In closed-type apartment systems equipped with gas or electric boilers (boilers), a safety module is usually used for ease of monitoring and maintenance. In contrast to them, units in private houses that run on solid fuels, as a rule, have a significant inertia, and therefore cannot stop instantly. This applies not only to pellet boilers equipped with automatic control systems, but also to devices in which wood is used as fuel.
If the normal operating mode is violated, the built-in thermostat or other control device is triggered instantly, but the process cannot stop immediately. Firewood cannot go out instantly, but will smolder for some time, resulting in a slight increase in water temperature. In this case, the installation of a safety group will help to prevent an accident in a solid fuel boiler.
Self-assembly instructions
If a wood or coal boiler purchased from a store does not have its own protective assembly in the kit, you can buy it separately and then install it on the equipment yourself. In this case, the focus is not so much on the company that produces this combined product, but on the correct choice of the devices themselves. Not all safety assemblies offered by manufacturers are suitable for a specific heat generator model.
As a rule, the characteristics of the air release device are not decisive and this component of the unit can be ignored.
In contrast, the pressure gauge and the safety valve are selected in accordance with the value of the maximum pressure, the value of which is given in the operating instructions for the boiler equipment. Only after making sure that they are suitable for a given boiler sample, you can buy a product and proceed to installation. From a technical point of view, the installation of a safety group on a heating unit is not particularly difficult. All that is required for this is to stock up on a basic set of plumbing tools. If available, the connection to the heating system is carried out in one of the following ways:
- installation of the purchased module on the union already available on the manifold of the boiler in use - in this case, you will need to follow the coincidence of the thread indicated in inches;
- insertion of the body of the safety unit into the supply pipeline in the area of its outlet from the heat generator.
When installing safety elements, it is important to remember a few points regarding the connection features of this device.
Sometimes, for better visibility of the instrument panel, the entire group is installed on a vertical section of the pipe. Alternatively, it can be located on a bracket specially equipped for this purpose, fixed to the wall. A transparent hose is connected to the outlet of the safety valve, the other end of which is lowered into a plastic canister or directly into the drain. The first of these drainage schemes is good in that it is convenient to judge by the water level in the tank that the boiler is operating in a critical mode.
Groups for boilers from imported manufacturers
Users of popular imported boilers also have to monitor the operation of heating equipment. It is for these purposes that a security group is established, which is selected for each of its specific types separately. Common products of this class are on sale, such as the Valtec VT.460.0.0 security assembly, for example. In addition, in the domestic market, models for the Watt KSG 30 boiler for 3 bars, well-known to many users, are widely represented.
Safety groups from the well-known manufacturer Meibes, whose product catalogs are known all over the world, also belong to the category of fittings in high demand for heating equipment.
