Automation for domestic gas heating boilers. Types of automation for gas heating boilers

The control of modern gas heating boilers is unthinkable without the use of automatic control systems. It is thanks to them, automatic systems, that the owners of private houses have the opportunity to leave their gas boilers unattended, turn them on and off remotely and be sure that the devices work in the optimal mode, the most efficient and economical.

It should be noted that automation for gas boilers, first of all, makes their operation safe, and secondarily, convenient. It is unlikely that gas heating boilers would have become so widespread if there were no reliable automatic control systems.

Types of automatic systems for gas heating boilers

Automation for heating boilers is of two types:

• Volatile, working when connected to the mains
• Non-volatile, operating without the consumption of electrical energy

Volatile automatic control systems differ depending on the set of functions performed. The simplest of them ensure the safe uninterrupted operation of the device, while the most complex models of automation systems allow you to heat the house in accordance with the selected operating modes, taking into account whole line parameters. It could be the temperature environment, time of day, presence or absence of people in the house and much more.

non-volatile gas equipment choose for installation in houses with unstable power supply or where there is no electricity at all.

How non-volatile automation works

Non-volatile automation controls the following parameters:

• traction level.
• Heat carrier heating temperature
• By the presence of a flame

To control the draft level of this, a draft sensor is installed in the chimney. If the vacuum in the chimney is sufficient, the boiler works, if there is no draft, or the chimney is blown by the wind, the gas supply to the gas burner is blocked and the combustion process stops completely. It should be noted that control over the draft level is especially important during the operation of any heating boiler, because it depends on the level of vacuum in the chimney whether the combustion products will be completely removed or not and whether they will get inside the room, creating an emergency.

Therefore, without exception, all gas heating boilers are necessarily equipped with draft sensors.

The second important parameter is the heating temperature of the coolant. To control it, a thermocouple is used, which changes its size depending on the heating temperature of the coolant. If the water temperature in the boiler is below the nominal value, the thermocouple acts on the connecting valve, increasing the gas supply to the combustion zone.

If, on the contrary, the heat carrier temperature is too high, the thermocouple transmits a signal to reduce the gas supply to the combustion zone, thereby eliminating the possibility of overheating the water in the boiler and boiling it.

Another important aspect of the safe operation of a gas boiler is the possibility of gas leakage from the combustion zone. To do this, the ignition of the boiler is carried out in two stages. At the first stage, an igniter is ignited, which provides heating of the thermocouple located in the combustion zone. Gas supply and ignition of the burner is possible only when warmed up to certain temperature thermocouples.

If, for some reason, the flame goes out, the temperature of the thermocouple will drop, resulting in blockage of the gas supply.

A simple example: the pressure in the gas pipeline dropped sharply, the burner went out, and after a few minutes the gas supply was resumed. If there were no protection system, there would be a gas leak.

Volatile automatic control system

The volatile automatic control system allows solving all of the above tasks, as well as a whole range of additional tasks. Its main advantage is to create a higher level of comfort.

If a non-volatile system eliminates the possibility of overheating of the coolant and its boiling, then more “smart” volatile automation allows you to control the heating temperature of the coolant with an accuracy of up to a degree, taking into account the ambient temperature, direction and strength of the wind.

In more complex automatic control systems, it is possible to set operating modes depending on the time of day and days of the week. With the help of automation, any possible emergency situations are excluded. For example, in double-circuit heating boilers, a protection system can be provided to prevent the coolant temperature from dropping below the minimum allowable value when heating water for hot water supply.

Especially when it comes to boilers installed in areas where low temperatures are not uncommon. The fact is that when DHW is heated in a double-circuit boiler, the heating of the coolant stops, which, with prolonged consumption of hot water, can cause hypothermia heating system, up to its defrosting.

It is only the automatic control system that can control such situations and turn off the DHW heating in a timely manner.

The list of possibilities for automatic control systems for gas boilers is large, in addition, it is constantly updated with new developments.

How to control the automation system

To control the volatile automatic control system, a display installed on the boiler itself or a remote control panel remote from the device can be used. For example, the panel can be located in the living room, while the heating boiler itself can be located in a special utility room.

The work of volatile automation for gas boilers is based on microprocessors, it is not surprising that today computers are increasingly used for effective control, and in the near future "smart" heating boilers will appear.

The principle of operation and control system of a gas boiler

The basic principle of operation of gas boilers is based on the fact that when gas is supplied to the boiler, electronic ignition or piezo ignition is switched on. The spark ignites the igniter, which burns constantly. Gas supply to the burner in the absence of a burning igniter is not allowed - such a situation is dangerous with an explosion. From the igniter, the main burner is ignited, which heats the coolant in the boiler to the specified parameters. After that, the automatic system switches off the burner. With a decrease in the temperature in the boiler, the temperature sensor (thermocouple) gives a signal to the valve to supply gas. And the burner ignites again.

Automation for floor boilers such as Buderus Logamatic 4211, 4212.

Boilers of modern production are equipped with all, as a rule, automatic control systems. Automation of gas boilers can be of very different degrees of complexity. These systems are designed to ensure the operation of the equipment (boiler) without the participation and constant supervision of people. Automatic systems for boilers perform various functions, including:

• safety;
• automatic switch on-shutdown;
• management according to different criteria: time, weather and others.

According to this, all elements of the boiler automation can be divided into several groups, in accordance with its type, device and functional purpose.

Gas fittings - an actuating device, one of those that work out the commands of the boiler control circuit. Changes in gas valve regulators trigger the processes of starting and stopping boiler equipment, as well as adjusting its power. The main purpose of gas fittings is to provide safe work boiler.

Boilers with built-in gas burners are equipped with gas valves with the main function - to open and stop the gas supply to the burner. These boilers include, first of all, wall-mounted gas boilers. They also include floor-standing boilers equipped with atmospheric gas burners.

Minimum pressure switch (gas)

Honeywell Brand Gas Valve for Small Boiler Equipment

Gas burners are designed to be used at nominal gas pressure - they are designed for this. It is with such indicators that the declared useful power of the boiler will be ensured. With a decrease in gas pressure, a drop in power is also observed. Boilers equipped with atmospheric gas burners are sensitive to a decrease in gas pressure - pipes can burn out. The falling pressure of the gas leads to the “settlement” of the flame so that the metal part of the burner is in the zone of the torch itself. And this can lead to breakdowns.

In order to protect the boiler and burner, a minimum gas pressure switch is used. The relay switches off the boiler when the pressure drops below the set value. The limit value can be changed during commissioning of the boiler. The gas pressure switch is structurally a kind of membrane that acts on a group of contacts. When the pressure decreases, the diaphragm moves under the influence of the spring and the electrical contacts switch. Switching contacts breaks the electrical circuit, which just controls the operation of the boiler. The power supply to the gas valve stops - and the boiler stops working. When the gas pressure is restored, the membrane will return to its original position, the contacts will switch again - and the boiler is ready to start again. Only here other processes are further determined by the logic of the actual control automation, and they may differ. Minimum pressure switches are mounted on the gas inlet to the boiler directly in front of the multiblock. Or in front of the front gas valve.

Dungs gas valve for floor standing boilers

Maximum pressure switch (gas)

Relay devices for maximum gas pressure are designed to protect boilers from possible overheating or from the danger of destruction due to an uncontrolled increase in pressure on the burner. This can lead to an increase in the size of the torch itself and, as a result, to burnout of the combustion chamber, which is not intended for this. In addition, gas valves with increasing gas pressure may not close. The rise in pressure can also be provoked by a breakdown of the gas fittings on the supply line.

The relay is connected in series with the minimum pressure switch. This is done in such a way that the operation of any of them somehow turns off the boiler. Structurally similar relay is made similarly to the first one.

Thermostats for heating boilers are perhaps one of the relatively simple electromechanical devices used in the control circuits of this equipment. Their main purpose is to maintain the specified parameters of the temperature of the coolant in the boiler. It is also possible to limit this temperature to the maximum and minimum. Thermostats, thus, can be attributed both to the control devices of the automation of boiler equipment, and to safety devices.

Controller

Controllers are special electronic devices that are designed to implement a rather complex algorithm for controlling a heating installation under changing environmental conditions. Controllers differ in their functions and capabilities. But all have special temperature and pressure sensors. Controllers are well classified. They are distinguished by control algorithms, by control objects, by direct integration with the boiler, by communication capabilities, etc.

(description)
There are two boilers in the boiler room (Vitoligno-100 and Vaillant models). Heating controller brand Kromschroder E8.0634. When the Vitoligno-100 boiler is flooded, the operation of the second boiler (Vaillant) stops synchronously. The drive closes the heating pipe of the gas boiler, connecting the pipe of the solid fuel apparatus. The solid fuel boiler operates on a storage tank, from which hot water enters the heating system. At the end of the boiler, the work of the tank also ends, the temperature drops below 30 degrees. The gas boiler is turned on again, the heating system receives heat from it directly. The water in the boiler is heated from the storage tank if the temperature in it is above 50 degrees. In the case of lower temperatures, the gas boiler provides hot water. The whole system works automatically. Two heating circuits: one is a radiator type, the other is a floor heating type. Installed a pair of mixing units.

Security automation

The relay of the minimum and maximum pressure of the heat carrier

An important element in the boiler safety system is such a factor as protection against emergency pressure reduction in the system. Falling can occur due to various reasons, including leakage, breakage expansion tank or failure safety valves. The low pressure of the coolant can cause it to boil in the system, as well as airing it, which can lead to a cessation of circulation through the boiler and, as a result, to overheating.

Protection against such falls can be ensured by installing a special relay (minimum pressure) on the pipeline next to the boiler. It is a membrane on which the coolant presses. The membrane is connected to a whole system of electrical contacts. When the pressure in the system falls below the set values, the contacts switch over. As a setting point, the minimum allowable values ​​of the coolant pressure are chosen, at which the system will be operational. The relay is connected by electricity to the common burner control circuit. When the pressure drops, the burner will stop.

No less dangerous is an excessive increase in pressure. For emergency shutdown of the boiler when the pressure rises above the operating values, a maximum pressure switch is used. It is similar to a minimum relay, but only has the opposite purpose - it switches contacts above the set point. The relay is also included in the electrical circuit of the burner.

Both types of relays come with automatic restart and manual.

In the first case, when the parameters are normalized, the electrical contacts return to their original state and the boiler automatically resumes its operation.

In the second case, operator intervention is required to start the relay. Typically, this type of relay has two contacts. One is connected to the burner, the second is connected to a signaling device (lamp, buzzer). When the relay is triggered, the panic button will turn on.

Coolant presence sensor

Other boilers can fail even during short-term operation in the absence of a coolant. To prevent such situations, a sensor for the presence (or absence) of a coolant is designed. This is especially important for electric boilers with heating elements. The sensor is installed either next to the boiler or inside. It is included in the control circuit of the device and closes the contacts only when the block is filled with coolant. The most common devices are reed switches and conductometric sensors.

In the first, the magnetic core is built directly into the float, which, when floating up, closes the contacts only in the presence of liquid.

The second type of sensors are special electrodes placed in the hydraulic circuit. When the boiler is filled with coolant, a current sometimes flows between the electrodes. A closed circuit is a sign of the normal situation of the coolant and a signal about the operation of the boiler.

Boiler priority relay

Domestic boilers for the most part have the ability to connect to wiring diagram target that controls the DHW cylinder. This involves, among other things, the connection of the power supply of the circulation pumps and their switching. For the correct implementation of the operation algorithms of the heating system pumps and the boiler (which is aimed at the priority of water heating), a special boiler priority relay is used. This is a device that switches the power circuit of the pumps according to the commands of the boiler control circuit. The relay is structurally a couple of groups of contacts controlled by a coil. The relay is used together with the base, which is built into the boiler. The entire load is attached to the base. When installing a base relay, the priority of the DHW system is ensured. Without such a relay, both thermal loads function independently.

Gas boiler room in a private house: VIDEO

Self-repair of damaged boiler automation is not only unpleasant, but most often almost hopeless, since boiler passports are not written for these purposes. And without exact knowledge of the circuit and all the subtleties of the device of the automatic system common man(not an electronics engineer) it’s better not to even start. Of course, I will not discover America if I say that best solution will initially take a boiler with reliable automation from a reputable manufacturer, so you are less likely to run into trouble.

Bimetal radiators are something like a compromise between clumsy cast iron and cheerful, but not very reliable aluminum batteries. stainless steel did its job - bimetal is much more resistant to aggressive environment, I mean our mercilessly harsh domestic coolant. Quite recently, I myself literally fought for cast iron, and now exclusively for bimetal radiators I advocate - in terms of a set of characteristics, they win. And most importantly - good heat dissipation.

Why do you need automation for gas heating boilers?

When considering home heating options, most often they stop at using a gas boiler. Available close to home main gas pipeline this heating option is considered the most economical and efficient.

When installing any heating boiler, including gas, a mandatory component of the system is automation. Such automation for heating boilers allows, without human intervention, to maintain the specified climatic conditions in a heated room and ensure optimal operating conditions for such a boiler.

What does automation for gas heating boilers consist of

Typically, such automation includes the following elements:

• fittings. These are actuators that, under the action of commands, turn on and off the start-up of the boiler, as well as regulate its power;
• valves designed to cut off the gas supply;
• maximum and minimum pressure switch. Designed to protect the system when pressure drops or increases too much;
• thermostat;
• water and gas pressure sensors;
• controller - electronic device, which calculates the optimal mode of operation of the gas boiler from the received data and generates control commands.

Types of automation for heating boilers

From the point of view of power, automation for gas boilers is of two types:

• non-volatile automation;
• volatile automation.

These two types of automation differ in that the first system does not require power from the mains, and for the second to work, electricity must be supplied.

Accordingly, these two automation systems will include different elements.

Learn how to repair a heating pipe without welding yourself.

These automation systems include:

• ignition system, which is used as a piezoelectric element;
• thermostat;
• draft and flame sensor.

Mechanical automation starts working after the boiler is started. Depending on the temperature of the heated water, the thermostat changes the amount of fuel supplied to the burner. Structurally, the thermostat is a metal rod. It changes its length as the temperature changes. Thus, it opens or closes the gas supply.

The draft and flame sensor is designed to interrupt the gas supply when the burner flame goes out or the draft in the chimney is poor. Structurally, such a sensor consists of a bimetallic plate, which, under the influence of temperature, changes its position and closes the gas supply.

Of the control and measuring equipment in such systems, a pressure gauge and a thermometer are used. Such a system is configured manually.

Modern non-volatile automation systems for gas boilers can have a much larger number of nodes. For example, Italian non-volatile automation has the following nodes:

• system of inclusion and management of temperature;
• flame protection system;
• device for setting the minimum gas flow;
• pressure regulator;
• thermostat with burner shut-off function.

For regulation in volatile automation, electromagnetic valves are used. The operation of these valves is carried out according to commands generated in the processor. Using a special display, the operator can select one of the possible modes. A correct execution this mode will provide automation.

From the point of view of the functions performed, automation for gas heating boilers can be of two main types:

• room thermostat;
• weather dependent.

In the first case, the main indicator for controlling the operation of a gas boiler is the temperature in the room. Depending on this temperature, the operating mode of the boiler is selected. When the temperature in the room drops, the boiler starts to work, and when the temperature exceeds the set level, it will turn off.

Thermostat designs may vary. For example, the SEITRO thermostat operates using a membrane sensor. At a certain temperature, the sensor closes and a switch-on command is transmitted to the gas boiler.

SEITRO thermostat

A kind of thermostat is a programmer. From such a programmer, commands are transmitted to the gas boiler during the day, in accordance with which its mode of operation is carried out. Every day the cycle is repeated.

Basic functions of automation

The main functions of automatic gas heating boiler are the following functions:

• automatic start of the gas boiler;
• stop the operation of the gas boiler;
• control and adjustment of the burner power using an appropriate sensor;
• emergency stop of the gas boiler in case of any malfunction.

When you turn on the gas boiler, the automation first starts the hardware of the system. With this, the temperature is measured and the amount of gas that must be supplied to the gas burner is estimated. At the next stage, the automation starts the gas fittings, as a result of which gas is supplied to the system. At the same time, a spark is ignited in the combustion chamber, which ignites the gas. Under the action of a flame in the heat exchanger, water is heated, which is then fed into the batteries.

We choose a reliable and inexpensive thermostat for a heating radiator here.

One of the options is sub-automatic for a gas heating boiler

An important part of the automation system of a gas heating boiler is the security subsystem. This includes:

• overheating protection;
• frost protection;
• anti-blocking;
• anticyclic function;
• flame and draft control.

Anti-blocking provides automatic activation of the pump every 24 hours in order to combat scale. The anti-cycling function assumes that the automation prevents frequent ignition of the burner, which reduces its operating life. When a signal of the absence of a flame or draft appears, the automation system turns off the gas supply.

In volatile automation systems, the gas supply is turned off using a solenoid valve through which the gas enters the burner. The valve automatically turns off even if the gas stops flowing. The disadvantage of such a valve is that when gas appears, it cannot open automatically and you have to do it. manually. At the same time, in case of power failures, after the restoration of the electrical circuit, the system starts automatically.

Modern automation systems for gas heating boilers allow reliable and safe operation of gas boilers

V modern systems automatics for a gas boiler, the diagnosis of a system malfunction is performed automatically. The results of this diagnostic are displayed. This greatly facilitates and speeds up the repair of a gas boiler.

When choosing which automation to buy for a gas boiler, you need to understand that the most modern systems are volatile. If the customer has doubts about the reliability of the electrical network in his house, then it is necessary to consider the use of non-volatile automation systems.

Why do you need automation for gas heating boilers?

The principle of operation, advantages and disadvantages of automation systems for gas heating boilers are considered.

AUTOMATION FOR GAS BOILER

The problem of heating and water heating in country houses, to which gas communications are connected, it is easiest to solve with the help of a gas boiler, which occupies a central place in the heating system. Organizing the latter in their home, consumers try to choose the most simple and easy-to-use boiler.

Therefore, equipment developers equip gas-fired boilers with special automatic devices that not only control its operation during operation, but also provide high level safety in case of emergency.

In general, boiler automation devices include:

• gas valves;
• various control sensors (heating, gas presence, etc.);
• control units;
• security systems.

Goals and tasks of automation.

The efficiency and safety of operation of a gas boiler depends on compliance with the established operating modes for a long period of time. Moreover, its owner does not always have the opportunity to control the compliance of the operating parameters with the set values.

In accordance with the current regulatory documents, automation equipment installed in gas heating boilers must cut off the gas supply in the following cases:

• insufficient draft in the chimney;
• lack of flame on the igniter;
• low or too high gas pressure.

Boiler automation helps to solve these problems. It is she who is able to ensure that all operational requirements are met, as well as inform the owner of the boiler about violations in its operation. Currently, all gas boilers are necessarily equipped with automatic control systems, which, largely determining their functionality, affect the operation of the heating system as a whole.

The main classification of automation devices for heating boilers provides for dividing them into two types:

1. Non-volatile - the principle of operation of which is based on the use of mechanical devices.
2. Volatile - using complex electromechanical components and electronic devices in their work.

OPERATING PRINCIPLE OF BOILERS EQUIPPED WITH NON-VOLUME AUTOMATION

The start of a gas boiler equipped with non-volatile automation is carried out manually. When the start system button is pressed, the washer that shuts off the gas supply to the boiler is squeezed out, the valve is forcibly opened and the gas is supplied to the igniter, where it is ignited using a piezoelectric element.

Ignition of the gas causes a rapid (up to 30 seconds) heating of the thermocouple, which begins to generate a voltage that allows the electromagnet to hold the gas supply valve open. If for some reason the flame goes out, the thermocouple cools down and the valve closes, blocking the gas supply to the burner.

The functionality of boilers with non-volatile automation is extremely limited and comes down to setting the required coolant temperature, which is done manually. To do this, the boiler control panel has a temperature scale, according to which it is set working temperature coolant inside the boiler.

During operation, the set temperature is maintained using a special thermostat (thermostat), which opens or closes the gas supply valve as necessary.

The operation of the thermostat is ensured by a thermocouple built into the boiler heat exchanger. At the same time, it is equipped with a special rod made of Invar (an alloy of 64% Fe + 36% Ni), which reacts to temperature changes by changing the geometric dimensions of the part. With the help of this rod, which is rigidly connected to the gas supply valve, the flow of the latter into the burner is regulated.

The design of the draft sensor is based on a thin bimetallic plate, which in normal mode is in a bent state and holds the corresponding valve open. When the draft in the chimney decreases, the plate heats up, which causes a change in its geometric shape, and, as a result, the gas supply valve closes.

The gas pressure is controlled by a valve mechanism set to a certain value. With a significant deviation of the pressure value from the set value, the mechanism is triggered, shutting off the gas supply to the burner.

The advantages of boilers with non-volatile automation are:

• low cost;
• ease of control available to people who, as they say, are not friends with technology;
• autonomy of work for which connection to the power supply network is not required.

OPERATION OF BOILERS WITH ENERGY DEPENDENT AUTOMATICS

Work management modern equipment, equipped with a volatile boiler automation system, is carried out as a result of the analysis microprocessor unit control of data received from temperature, pressure sensors, etc. Almost all boiler controls are mounted inside its body, therefore, when installing the latter, it is enough to connect the necessary pipelines and connect the boiler to the public power supply.

Unlike boilers with non-volatile automation, the use of complex electronic devices significantly expands their functionality. In addition to the ability to independently maintain the set temperature of the coolant, modern control and measuring devices in automatic mode carry out:

• boiler start;
• control of the gas supply valve and burner power;
• shutdown of the boiler in case of emergency.

In addition, automated control units are equipped with special displays that display all the necessary information about the operation of the boiler.

Automated systems, thanks to the coordinated work of electronic devices, ensure the uninterrupted operation of the boiler in accordance with the established operating modes. They also allow the use of special programmers that allow you to set the temperature regime of the boiler for several days, taking into account the weather forecast.

The only drawback of boilers with an electronic automation system is their dependence on the stable operation of the public electricity network. In order to protect automation devices from power surges or power outages, it is recommended to use a voltage stabilizer. It is also desirable to provide for the installation of an uninterruptible power supply.

REMOTE CONTROL AND MANAGEMENT

A gas boiler, which serves as a source of thermal energy for the heating system, refers to equipment that has been operating continuously for a long time. At the same time, it can be considered as a set of devices designed to generate heat and automatic control by this process.

When developing such boilers, the developers set themselves the task of ensuring its stable operation with minimal user intervention. To do this, various sensors, control devices and actuators are introduced into the design.

However, their presence does not exclude the need, and in some cases the desire of the user, to additionally adjust the operation of the system at his own discretion. And the more complex the automation system, the more opportunities it can provide.

As a rule, the main user and service settings necessary for the normal operation of the boiler are displayed on the main panel located on the boiler body. Their user can change at any time. However, the heater is not always located close to the user. For example, in country houses, the boiler can be installed both in separate room as well as outside the home. In this case, the question arises of remote control of heating.

There are several options for implementing remote control.

With the help of room regulators, the most simple tasks- temperature control of the coolant. To do this, an appropriate sensor is built into the regulator body, which is connected to the boiler automation system. More complex devices equipped with electromechanical or electronic sensors and controls with their own autonomous power supply can also be used.

They are connected to boiler automation by wire or radio. The disadvantage of these devices is the lack of feedback - you can send a command, but you can not get information about the state of the system.

Remote controllers.

The remote controller is a more complex device connected to the boiler control system via a bus that transmits coded signals. Using the controller, it is easy to organize not only the control of almost all functions, but also provide feedback by displaying information about the state of the system and detected defects on the controller display.

The disadvantages of the system include the need to use control protocols, which make it difficult to coordinate the heating equipment with the controller.

The telecommunication module, equipped with a modem and a slot for a SIM card, in the presence of an appropriate controller as part of the boiler automation, makes it possible for the user to control the entire heating system at almost any distance from it. The telecommunication module can be installed anywhere and communicates with the boiler via a bus. The exchange of information between automation and the user is carried out using SMS-messages via GSM-communication channels.

Such an organization ensures that the user receives information about the state of the heating equipment and the impact on it in a timely manner using the appropriate commands sent from mobile phone. The only requirement that must be provided is the presence of a stable cellular signal.

Recently, telecommunication modules providing communication with the user via the Internet have become widespread. In this case, the module is connected to a working computer with Internet access, either directly or through a router. The signals are transmitted to a remote server, connecting to which you can see in real time and correct almost all parameters of the boiler equipment.

Messages about the appeared malfunctions and defects are transmitted to the user on email. With the advent of Android OS, the interface of which is similar to the interface of boiler automation control panels, it became possible to control the heating system using smartphones, which made remote control of the heating system even more convenient.

All materials presented on this website are for informational purposes only and should not be used as guidelines or normative documents

AUTOMATION FOR GAS BOILER

AUTOMATICS FOR A GAS BOILER

As you know, gas heaters are equipment that can create an emergency situation, associated with a mortal risk. Accidental flame extinction or gas leakage can lead to explosion or suffocation, and overheating of the boiler - at best, to its breakdown. Serviceable automatic safety of gas boilers will be able to prevent risks at an early stage. In addition, it contributes to a more economical use of the fuel resource and increases the level of comfort during the operation of the heating system as a whole. The cost of the automation unit depends on the number and complexity of the options included in the scheme. Some of them are mandatory, and therefore must be present in every gas boiler, without exception.

The principle of operation of basic automation

Modern heating equipment is certainly equipped with a security system and control units with the function of regulating operating modes. An element of basic automation is an electric or piezo ignition, which supplies a spark to the igniter at the moment the gas supply starts. To start the combustion process, you just need to press the button located on the body of the heating boiler.

Next, the machine turns on the gas burner, which picks up the fire from the igniter. After the coolant has warmed up to the required temperature, the automation (in this case, the thermostat) is triggered to turn off the burner, and when the water cools to the limit values, a signal is given to turn it on. The igniter continues to burn all this time. This option allows:

• protect the surrounding area from possible gas leakage;
• prevent water from boiling in the heat exchanger;
• stop the fuel supply to the nozzle in the absence of thrust or a sharp change in gas pressure in the main pipeline.

Maintaining the optimal operating mode of the boiler and the safety of the equipment have long depended not on the human factor, but on the automation that is equipped with gas equipment. It can be volatile, more reliable, but requiring an uninterruptible power supply, and non-volatile (mechanical), characterized by autonomy and a simple design. The security system may consist of only the necessary elements or be multifunctional, have manual control or a programmer.

Automation ensures reliable and economical operation of a gas boiler without human intervention.

Non-volatile system

Such automation is attractive due to its isolation from electricity, low cost and maintainability. The range of operating temperatures that affect the operation of the thermostat is set manually here by means of a switch connected to the thermostat built into the boiler. In its design there is a rod made of a material that can shorten and lengthen with changes in the temperature of the coolant. As a result, the gas supply valve opens or closes, completely shutting off the fuel supply to the burner.

The set of non-volatile automation also includes flame and draft sensors. In the event of a sudden attenuation of the burner, as well as with a significant decrease in thrust, the gas is instantly shut off. But for comfortable and economical operation of modern boilers, the above options are not enough. Manual regulation does not allow the use of equipment in optimal modes, therefore, savings, comfort and service life of the boiler without additional automation are minimized.

Volatile system

The maximum convenience of operation of gas heaters is provided by electronic automatic equipment. It is enough just to enter the operating parameters or already programmed modes on the display, as the regulation and control system comes into play. It functions based on the principle of solenoid valves receiving commands from a microprocessor unit.

The disadvantage of volatile automation is its attachment to electricity. In case of possible power failures, the equipment is blocked, and the coolant stops warming up, which leads to cooling of the heating circuit. The operability of the system and safety elements of the boiler is maintained by connecting the equipment to an uninterruptible power supply or to a diesel generator.

Modern automation is capable of:

• support different temperatures depending on the days of the week or time of day;
• regulate the thermal regime, taking into account weather conditions;
• create individual temperature in separate rooms;
• prevent freezing of the heating circuit;
• troubleshoot and much more.

Components of the automation system

Automatic control elements are divided into several groups, depending on the functional purpose and design features. When purchasing a boiler, it is necessary to familiarize yourself with the set of options presented in more detail, because the price of a gas boiler depends on their number. It is possible that too complex components are not required. Why then overpay?

Automation for heating boilers includes:

• thermostats;
• valves;
• relay;
• sensors;
• controllers.

Thermostats are considered one of the simple electromechanical devices in the automation system. Their functions include ensuring the specified temperature regime of the coolant and giving a signal to turn on or off gas burner after reaching the threshold, or boundary values.

Thermostats prevent water from boiling or freezing in the boiler.

The valves regulate the gas supply to the burner. Rather, they block or open the nozzle of the inlet pipe.

The coolant pressure switch in the system protects the gas boiler from serious damage. The fact is that too low pressure causes airing, boiling and stopping the circulation of water in the heating circuit. The result is a severe overheating of the boiler. Excessive pressure is no less dangerous, as it leads to an emergency and can provoke an explosion. In the first case, the situation is controlled by the minimum pressure switch, and in the second - by the maximum one.

Relay devices also control gas pressure. Normal operation of the burner is assumed at nominal pressure, therefore, when it is reduced or increased, emergency situations occur. In the first case, the flame begins to “settle” in the burner, which leads to the burning of the pipes. In the second case, it rises too high, as a result of which the combustion chamber suffers. Depending on the circumstances, the minimum or maximum gas pressure switch switches off the boiler in order to protect the equipment from serious damage.

Sensors that detect the presence of coolant in the heating system are an important addition to the boiler. They do not allow the equipment to be turned on without filling the circuit, which prevents the occurrence of emergencies. The sensor is made in the form of a float or electrodes placed in a hydraulic circuit in a certain way.

Controllers are electronic devices that control individual units or the heating system as a whole. At the same time, both internal factors affecting the operation of the gas boiler and external conditions, including weather, are taken into account. Controllers can have different capabilities and have different functionality. They are classified according to several positions:

• integration scheme with boiler equipment;
• management algorithms;
• set of features;
• service direction.

For gas boilers, there is a large selection of automation that allows you to safely and comfortably use heating systems. When buying equipment, you should familiarize yourself with the options offered by the manufacturer in detail. Mindfulness will help to avoid surprises.

For safe and efficient operation of heating equipment, it is recommended to install an automatic control system. Thus, in the event of a power outage, it will continue to work. You do not have to constantly monitor the heating device. Automatic systems for gas boilers can be divided into two types: volatile and non-volatile. Consider the principle of operation of automation, types of gas valves and the use of multi-block automation for gas units.

Types of volatile systems and the principle of operation

In order to avoid dangerous situations, it is recommended to purchase automation for a gas boiler. It is necessary to close and open the valve electronically. This happens after the temperature sensor gives a signal.

Devices that regulate the temperature in the house and ensure safety include:

1. The daily programmer can program all boiler operations for 24 hours. After a day has passed, the cycle will repeat. You can connect the programmer to the heating boiler wirelessly via radio or wired. Using a two-wire cable, you can connect the Saunier Duval ExaCONTROL daily programmer. It is necessary for time programming of the temperature in the water heating circuit and the temperature of the heat carrier in the heating circuit.
2. The room thermostat is connected to a cable. Such a device works according to a simple principle: after the temperature becomes required, a signal is sent to the gas supply valve, then the boiler turns off. If the temperature drops, the boiler automatically turns on. The electromechanical thermostat SEITRON TAM011MI is produced on the basis of a membrane block filled with gas. The thermostat can be controlled by a temperature sensor. If the temperature has become optimal, then the sensor closes or opens the contacts, so the boiler turns on or off.
3. Weekly wireless programmer. Consider the Auratin 2025 model, which can work between a receiver and a transmitter at a distance. If there are concrete walls, then the distance will be 30 meters, if in open space - 300 meters. The programmer can provide comfortable temperature in the room due to the high precision of adjustment. It is convenient to use the device, as the display has a backlight, and its color can be selected. You can set up 6 programs. You can connect an external temperature sensor, as there is a special connector.

The principle of operation of automation for gas boilers

The advantage of a non-volatile system is that no electricity is used during operation. Under the influence of temperature, the geometrical change of the control parts occurs and thus the valve is actuated.

Old models of non-volatile automation were difficult to regulate. In order to disable the device, it was necessary to use wire or electrical tape, and the safety of the entire heating system was significantly reduced.

This is not the case with modern systems. Therefore, the non-volatile automation 630 Euro Sit is reliable and safe. Main knots:

1. Pressure regulator.
2. Flame protection system. If the main burner is turned off, the gas supply is automatically blocked.
3. Main and outlet burner filters.
4. Device for setting the minimum gas flow.
5. Control knob with different positions: "ignition", "off", "temperature selection".
6. Fittings that are necessary to control gas flow.
7. A thermostat that has the function of completely turning off the main burner.

Depending on the choice of the consumer, the gas supply can be from below or from the side.

Types of gas valves

The main element of the automation system is the electromagnetic gas valve. Such a hydraulic device is used to regulate the gas flow by transferring power to the valve coil. The core, which is connected to the valve seat, is drawn into the coil by electromagnetic forces.

The valve can be of several types depending on the operating position of the seat:

1. Modulating valves are installed on gas boilers with the ability to smoothly change power.
2. Single stage valves. They have only two positions: "open" and "closed". After the power is supplied, the valve takes the extreme position and there is a full flow of gas for which the boiler is designed.
3. Two stage valves. Such a view can be fully opened with a time delay through an intermediate position. Thanks to this design, a smooth start-up of heating equipment occurs. One-stage and two-stage valves are used only for single-stage burners.
4. Three stage valves. Such elements can be installed on devices where there are two power levels.

The use of multiblock automation for gas equipment

Automation manufacturers sell ready-made blocks, which consist of a set of devices. For example, gas automatic systems manufactured by companies such as: Dungs, SIT and Honneywell.

The Elletrosit automation system includes the following elements:

• thrust sensor;
• Combined gas valve;
• Two-stage burner valve;
• Thermostat with temperature sensor;
• Gas pressure stabilizer;
• Limit thermostat with sensor.

The shut-off valve can be turned on and off using a thermostat that controls the temperature of the heat carrier in the circuit.

In such an automatic system, it is possible to connect a room thermostat, thanks to which you can ensure a comfortable temperature in each room in automatic mode.

Modern automatic control systems for gas boilers can not only control the start and stop of equipment, but also provide alarm, diagnostics, and power control of the unit.

Domestic heating boilers using natural and liquefied gas do not need constant monitoring by the user. Combustion and maintenance of the required coolant temperature are monitored by electronic and mechanical units built into any heat generator by the manufacturer. Our task is to explain how automation for a gas boiler works and what types of devices are used in modern water heating installations.

Automatic blocks of floor boilers

The vast majority of outdoor gas boilers are equipped with safety automatics that operate without an external power source (non-volatile). According to the requirements of regulatory documents, automation equipment must shut off the gas supply to the burner and igniter in three emergency cases:

1. Extinction of the flame of the main burner due to blowing out or for other reasons.
2. When there is no or sharply reduced natural draft in the chimney.
3. The pressure drop of natural gas in the main line is below the critical level.

For reference. The implementation of these functions is mandatory for gas boilers of all types. Many manufacturers add a fourth level of safety - protection against overheating. When the temperature of the coolant reaches 90 °C, the valve stops supplying gas to the main burner at the signal of the sensor.

V various models gas from different manufacturers, non-volatile automation of the following types (brands) is used:

• Italian blocks EuroSIT (Eurosit) series 630, 710 and 820 NOVA (heating units "Lemax", "Zhitomir 3", Aton and many others);
• Polish devices "KARE" (heat generators "Danko", "Rivneterm");
• American automatic control devices Honeywell (heaters of the Zhukovsky plant of the Comfort line);
• domestic products of ZhMZ, SABK, Orion, Arbat firms.

Fuel supply system in the simplest AOGV devices equipped with ZhMZ valves. The burner is hidden in the lower part of the body.

We have listed the most common brands of automation, which are often installed on hot water boilers of the same company. For example, the Zhukovsky plant completes budget versions of AOGV devices with its own ZHMZ safety units, heat generators of the middle price category with EuroSIT devices, and powerful models with Honeywell automatic valves. Let's consider each group separately.

SIT Group Brand Gas Valves

Of all the types of automation found in boiler plants, EuroSIT safety blocks are the most popular and reliable in operation. They are recommended by companies - suppliers of natural fuels, including for replacing the old gas equipment of boilers KCHM, AGV, and so on. They work without problems as part of Polidoro, Iskra, Vakula, Thermo and others microtorch burners.

The exact names of the three models used are as follows:

• 630 SITs;
• 710 MiniSIT;
• 820 NOVA.

Sockets for connection of thermocouple, main and pilot burner are located on the bottom panel of the valve

For reference. The SIT Group discontinued production of the 630 and 710 series, considering them obsolete. It was replaced by a new automatic safety of heating boilers - gas valves 820 NOVA, 822 NOVA, 840 SIGMA and 880 Proflame (powered by batteries). But old products are easy to find on sale.

In order not to bore you with the details of the design of automatic EuroSIT devices, we will briefly explain the principle of operation using the example of the simplest block of the 630 series:

1. When the handle is turned to the “ignition” position and pressed from above, you forcibly open the solenoid valve that passes gas to the pilot burner (igniter). You click the button of the piezoelectric element that generates a spark that ignites the wick.
   
2. By holding the main handle for 30 seconds, you allow the pilot flame to warm up. The thermal bulb generates a voltage (EMF) of 20-50 millivolts, which fixes the electromagnet in the open state. Now the handle can be released.
3. Set the main handle to the desired position and thus supply gas to the main burner. The latter ignites and begins to heat the heat exchanger with the water of the heating system, as shown in the diagram.
   
4. When the water reaches a certain temperature, a capillary sensor is triggered, gradually closing the second thermostatic valve. The fuel supply to the burner device stops until the sensor cools down and the valve plate opens the way for gas. The igniter continues to burn in standby mode.

Note. Older modifications of automation were not equipped with temperature sensors and ignition units, so matches were required to start the heat generator.

Scheme of connecting the automation unit to the gas burner

A membrane valve, which plays the role of a pressure regulator, is responsible for the normal supply of gas in the device. When it falls below a predetermined value, the fuel channel closes and an emergency shutdown of the boiler occurs. Other situations lead to refusal:

1. The burner and the wick that heats the thermocouple go out. Voltage generation stops, the solenoid valve closes the fuel passage.
2. If the draft in the chimney unexpectedly disappears, the sensor located in this channel overheats and breaks the power supply circuit of the electromagnet. The result is similar - the fuel supply is blocked.
3. In heaters equipped with overheating sensors, the electrical circuit is broken after the water reaches a temperature of 90-95 °C.

When the gas automatics triggered an emergency shutdown, the restart of the boiler by the user is blocked for 1 minute, before the fuel supply is resumed. The operation of the system is clearly reflected in the training video:

Differences between the 710 MiniSIT and 820 NOVA models

According to the principle of operation, these blocks do not differ from their predecessor - the 630th series. Changes in automation 710 MiniSIT - purely constructive:

• 2 buttons "Start" and "Stop" are taken out separately together with the solenoid valve;
• the main handle only rotates the thermostat rod and regulates the temperature of the coolant;
• an ignition unit with a piezo igniter button is built into the product body;
• included in the basic package of the device temperature sensor bellows type with capillary tube;
• added gas pressure stabilizer.

In block 710 MiniSIT, the handle acts as a temperature regulator and puts the heater into standby mode with a burning igniter

For reference. In the first versions of the 710th family, a spark igniter was not provided.

The latest 820 NOVA product line has been redesigned to improve stability, reliability and throughput. We want to highlight 2 improvements that are important from a user perspective:

Non-volatile room thermostat connection scheme

In this section, it makes sense to mention Honeywell automatic gas valves, which work in a similar way. Their main difference is the increased throughput, which allows the blocks to be used in high power boilers (30-70 kW).

Polish automatic "Kare"

Few manufacturers practice the installation of Polish security systems on gas boilers. The reason is banal: in terms of reliability, the product loses to products from Italy, the USA and Germany, but at a price more expensive than domestic boiler automation.

We called the product "system" because it consists of several blocks, although general principle action remains unchanged:

• gas filter;
• valve - gas pressure regulator;
• a thermostat with an adjusting handle is separately installed;
• membrane thermostatic valve;
• piezoelectric igniter button.

Scheme of the Polish system "Kare"

The nodes and sensors are interconnected by capillary tubes. In fact, this is the same SIT or Honeywell device, only broken into separate parts. This is a plus: it is more convenient and cheaper to change parts.

Products of domestic firms

As you understand, the automation of the boiler, made in the post-Soviet space, does not contain any revolutionary solutions and technological breakthroughs. To implement the three safety functions, the same principles are used - the inclusion of an electromagnet by voltage (EMF) of a thermocouple, a membrane gas valve and a draft sensor that breaks the circuit.

Scheme of the ZhMZ safety valve

It makes no sense to talk in detail about the design of blocks from the brands SABK, Orion and ZhMZ (Zhukovskiy Zavod). These products are characterized by the simplest device, low cost and low reliability. Thermocouples burn out almost every year, and the thermostat turns off and starts the burner too abruptly, which causes a loud bang, sometimes looking like a microexplosion.

The devices work normally in the first years of operation, then they need to be monitored and, fortunately, spare parts are available for sale and are inexpensive. An example of eliminating a typical malfunction of ZhMZ automation, see the video:

Electronics of wall units

The peculiarity of these heat generators is electronic control processes of ignition, combustion and maintaining the temperature of the coolant. That is, wall-mounted gas boilers (and some floor-standing ones) are equipped with volatile automation powered by electricity.

An important point. Despite the many "bells and whistles" introduced into the design of mini-boiler rooms, mechanics are still in charge of safety functions. The three types of emergency situations listed above will be processed by the equipment regardless of the presence of voltage in the mains.

The automatic gas boiler was created for the maximum convenience of the owners of apartments and private houses. To start the heater, just press 1 button and set the desired temperature. Let us briefly describe the algorithm of the unit operation and the elements involved in it:

1. After the specified start-up actions, the heat generator controller collects sensor readings: coolant and air temperature, gas and water pressure in the system, checks for draft in the chimney.
2. If everything is in order, the electronic board supplies voltage to the electromagnetic gas valve and at the same time - a discharge to the ignition electrodes. The wick is missing.
3. The main burner ignites and gives full power in order to speed up the heating of the coolant. Its work is monitored by a special flame sensor. The controller includes a built-in circulation pump.
4. When the coolant temperature approaches the set threshold, which is recorded by the overhead sensor, the combustion intensity will decrease. Step burners switch to low power mode, and modulating burners smoothly reduce the fuel supply.
5. Having reached the heating threshold, the electronics will shut off the gas. When the sensor detects water cooling in the system, automatic ignition and heating will be repeated.

Note. In turbocharged boilers with a closed combustion chamber, the controller also starts and stops the fan.

The instructions for the wall-mounted gas boiler indicate that the unit is designed to work in closed system heating, so the automation monitors the water pressure. If it falls below the permissible limit (0.8-1 bar), then the burner will go out and will not light up until the problem is fixed.

Many imported boilers operate according to a volatile scheme, for example, Buderus Logano, Viessmann and so on. How the installation of electronic gas equipment takes place, the master will tell in an accessible language in the video:

Conclusion

Many homeowners do their own maintenance of their heating units. Hence, interest arises in the operation of automation of gas boilers of various types. We have covered this issue, but we do not recommend repairing safety valves yourself if you do not understand the topic. The maximum that can be done is to clean the strainer, replace the unusable membrane or electromagnet. It is better to entrust the setting of the burner or igniter flame to a master gasman.

Note. The article uses materials from the manufacturer of boilers "Lemax", posted on