As you know, our country is constantly working on gasification of the private sector. Most future owners of gas heating systems are concerned about the choice of a gas burner for boilers that were originally used to burn solid and liquid fuels. This publication will discuss the main types of household burners, their design features, advantages and disadvantages.
Classification and principle of operation
A gas burner for a heating boiler is a fairly technologically advanced device that is responsible for creating a gas-air mixture in a strictly defined proportion. From the device, the mixture enters the fuel chamber, where it is ignited by an electric discharge or a spark of a piezoelectric element. Depending on how the fuel is mixed with air, these devices can be divided into: diffusion, injection, recuperative, regenerative.
Depending on how the flame is adjusted and controlled, these devices are:
- Single stage. To heat the coolant, the device operates at full power. When the heat carrier reaches a temperature determined by the user, the temperature sensor gives a signal, and the automation closes the gas valve. In this case, the burner stops functioning. When the coolant cools down to the lower temperature value, the valve opens, and the fuel-air mixture ignites again in the fuel chamber. In this case, the device operates at its maximum from its power.
- Two-stage. When starting the boiler, for quick heating of the heat carrier, the burner operates at 100% capacity. After reaching the upper temperature limit defined by the user, the gas valve is closed, providing the device with the necessary amount of fuel, sufficient for the operation of the device, with a capacity of 40%.
- Continuously adjustable. With such an adjustment of the gas burner of the boiler, the flame also does not go out, but the change of modes from 100% to 40% of the power does not occur abruptly, but more smoothly.
- Modulated. Gas burner equipment of this type automatically changes performance. This is what allows you to automatically maintain the temperature set by the user, which provides comfort for the user and significant savings in fuel burned.
The effect of using modulated models is 5 — 15% gas savings. Depending on the design of the flame adjustment module, this type of equipment is produced with a mechanical, pneumatic and electronic control system. The use of modulated gas burner units in boiler units significantly reduces the heat load on the heat exchanger, which has a positive effect on its service life.
Departing from the topic, we want to inform you that we have prepared comparative reviews on gas boilers. You can get acquainted with them in the following materials:
Atmospheric appliances for combustion of gas-air mixture
The scheme of operation of atmospheric burners of a domestic gas boiler is quite simple: fuel is supplied to the device through an ejector. Due to the high speed of the fuel jet, a low pressure area is created around it, due to which air is mixed with gas. Through the tubes, the mixture enters the holes through which it enters the firebox, where it is ignited by electric ignition. The main advantages of this design:
- silent operation.
These advantages allow the use of atmospheric gas burners in almost all types of heating boilers that use natural gas as fuel.
The disadvantages of the device include the following:
- Decreased oxygen concentration in the room where the heating boiler is installed.
- With insufficient draft, combustion products enter the boiler room.
As a rule, atmospheric burners are installed in boiler units with an open combustion chamber, therefore they require a stationary chimney.
Turbine installations for heating systems have a rather complex design. The device of a gas burner for a heating boiler includes:
- Electric motor with rotary fan wheel.
- Air grille and gas throttle servos.
- mixing device.
- Flame control sensor.
- Electric or piezo ignition electrodes.
A feature of turbine models is the presence of a gas module in the design: with a fuel filter, a pressure reducer, a device that regulates gas flow, automation that controls the relationship between the fan speed and fuel supply, and is also responsible for turning off the gas supply to the burner when the turbine stops. Most often, this type of equipment is installed in boiler units with a closed fuel chamber and additional fans installed to force the removal of combustion products of the gas-air mixture.
The main advantages of turbine devices:
- High performance safety of use due to the control and security system.
- Confident operation at low pressure of natural gas in the gas pipeline.
- There is no need for a stationary chimney.
In addition, when using fan models, manual adjustment of the gas burner of the boiler is not required. The design of the turbine burner provides for an air damper, the position of which is controlled by a servo drive, which is responsible for the volume of air in the gas-air mixture.
Disadvantages of turbine models:
- High cost, which is several times higher than that of atmospheric burners.
- High noise level generated during the operation of the turbine and additional fan.
Tip: for the operation of the protection systems and the turbine, this device requires electricity. That is why, in order to eliminate the risk associated with volatility, it is recommended to connect via an uninterruptible power supply.
There is another type of burners — diffuse-kinetic. The principle of creating a gas-air mixture is as follows: the oxygen necessary to maintain the combustion process simultaneously enters the fuel chamber and directly into the torch. Such devices are practically not used in domestic heating systems.
Today, most manufacturers of heating systems have launched the production of combined burners, which allow using almost any type of fuel as fuel without reconfiguring the system and additional equipment.
Burners of this type have a rather complex design, which leads to their high cost. That is why the combined models did not find great demand among our compatriots.
Criterias of choice
The correct choice of the gas burner device ensures the correct, complete and constant combustion of the fuel even with gas pressure fluctuations. Complete combustion of gas ensures high efficiency and obtaining a mixture of gases that is practically safe for humans during fuel combustion.
When choosing this device, you should pay attention to its design, technical characteristics, the principles of creating a fuel mixture and its supply to the combustion chamber.
- Based on operating experience, the most durable are structurally simple gas burner equipment. Complex devices, most often fail quickly enough due to high temperatures in the combustion chamber.
- It is recommended to use models with the same section of holes for the passage of the gas-air mixture. Adjustment of air and fuel flow should be carried out by means of throttle devices installed on underwater air and gas communications.
When buying this device, pay attention to its labeling. For example, the letter “G” in the marking indicates that it is intended for gas boilers. The designation “GM” indicates that this model is intended for boilers that use gas and fuel oil as fuel. The letter “P” indicates that you have a rotational model in front of you. The designation “RP” means rotary with the right rotation of the rotor; “RL” — with left rotation of the nozzle rotor.
If you decide to make your own choice, then you should pay attention to the following equipment:
KChM is an extremely simple and reliable device equipped with three nozzles.
Most often used by our compatriots when transferring boiler units from solid fuel to natural or liquefied gas.
Ochag is a fully automatic, pneumomechanical gas burner equipment with a three-stage safety system.
The model is equipped with an automatic gas pressure regulator, which ensures uniform combustion of the mixture even with pressure drops in the system.
“Cooper” is a combined device that can operate on almost any type of fuel.
The main advantage of this device is the ease of installation.
Tip: The right choice of gas burner equipment requires special knowledge and experience. That is why it is recommended to entrust the choice of the necessary model to professionals.
Like any equipment, a gas burner needs maintenance. The legislation prohibits intervention in gas equipment, so you have to resort to the services of certified specialists. Despite this, cleaning the furnace and burner can be done independently. The main stages of work:
- Shutting off the gas line and disconnecting the boiler from the power supply.
- Dismantling the device.
- Cleaning of carbon deposits that could form on the ignition electrodes.
- Cleaning the combustion chamber.
- Replacing the gas valve filter.
After cleaning, it is necessary to assemble the device in compliance with the necessary clearances, which are set out in the technical requirements and are in the passport for the boiler. After the assembly process, it is necessary to configure and adjust the device.
These works are carried out using a gas analyzer, which is mounted in the chimney and examines the chemical composition of the exhaust gases. We strongly recommend that you contact companies that have a state certificate authorizing this work to adjust the operation of the burner.