The gas column is a running water heater, running on natural gas. If you do not have hot water supply, but gas is supplied, this equipment will increase the comfort of your life. You just open the tap, hot water runs from it, and its temperature is regulated by yourself. Even if you have a centralized supply of hot water in a house or apartment, but you are not happy with the price you have to pay for heating, or maybe you are not comfortable with the temperature, installing a gas column will also solve these problems. Heating water costs a lot less than it is provided centrally - that's significant savings on utility bills. In order to understand which gas column is best, it is necessary to study the structure of the equipment and its types. Then the choice for you will be simple and conscious.
The structure of the gas column
Flowing gas water heaters consist of three main units:
- gas burner and gas exhaust system;
- heat exchanger;
- ignition and control module.
All these nodes have several modifications and their layout gives different models with different characteristics. All this allows you to choose the unit for your own requirements, because you can tell which gas column is best, you can only be attached to a specific situation.
Kind of ignition
In order for the column to start its work, it is necessary to ignite the gas. Old models were lit by hand, bringing a burning match to the igniter. Today such units are not on sale anymore, they are in the past. They were replaced by others who work in automatic or semi-automatic mode.
In gas columns with a piezoelectric element, the ignition occurs in a semi-automatic mode. There are two burners - the main and pilot. A pilot burner is a small wick that burns constantly, regardless of whether there is a hot water flow or not. The main burner switches on only when the tap is open. All the rest of the time it's off.
The order of starting a gas column with a piezo spark is simple: press the button on the front panel, a spark appears on the candles, which lights the pilot burner. When the hot water tap opens, the gas is supplied to the main burner, the ignition comes from the pilot burner. While there is a flow of water, both burners burn. The crane was closed, the supply of gas to the main stopped, again only the pilot burns.
What are the advantages of gas columns with piezoelements? These are the cheapest models, they usually have a mechanical control - a regulator that allows you to change the height of the flame, thereby adjusting the temperature of the hot water. These models are not energy-efficient, which can be important for giving.
There are more drawbacks and they are more serious. The wick burns (should burn) constantly while you use the column, and this is the gas flow. Let it be small, but permanent, as a result, for a month runs quite a decent amount. So this is not the most economical way to heat water. The second minus is also associated with the burning of the wick. If it goes out, you will not be able to light the column. The wick is extinguished because it lacks oxygen for combustion, or because a reverse draft is periodically produced in the chimney, which blows out the flame. Since there is a fire controller, this is not fearful - the gas is automatically shut off, but the need to light the pilot burner again is unpleasant.
Automatic gas columns have an electric fire. It is a spark generator that is activated when the crane is opened. The rest of the time the gas does not burn, which saves fuel significantly. There is an electric ignition, working on batteries, there is - from the network of 220 V. Which gas column is best for this parameter is chosen according to the circumstances.
If you often turn off the light, it makes sense to choose a model that runs on batteries. As you know, in this case, you have to ensure that they do not "sit down." If there is no electricity problem or there is a backup power source, it is better to choose a gas column powered by 220 V. Once the cord was plugged into the outlet and forgotten about it. The consumption of electricity is scanty, so that they have almost no influence on accounts.
Gas vending machines are electronically controlled. In the case there is a board with a microprocessor, the desired temperature is set from a small control panel (push-button or sensor). Immediately often put a small liquid crystal screen, which displays the current state of the equipment, the water temperature, if it is heated. This type of gas column is best, if you appreciate the convenience of handling.
Disadvantages - a higher price and demand for power. The electronics need a stable voltage of 220 V with small deviations of the order of 2 * 3 V. We do not maintain such parameters, so that in order for the automatic gas column to work for a long time, a stabilizer is required, and not a relay one, but an electronic one. It not only stabilizes the voltage, but even outlines the shape of the impulses, which is also very important for imported water heating columns.
Burner, combustion chamber, chimney
The water in the gas column is heated by the heat released by the combustion of the gas. The combustion itself occurs in the burner, and it is "packed" into the combustion chamber. Unburnt gases that remain in the chamber are diverted through the chimney. Let's consider all these devices in more detail.
The source of heat in the gas column is a gas burner. There are three types: one-stage, two-stage, modulated. The first two species have not been found in recent times - they do not allow maintaining a given temperature, therefore, there is no point in considering them - all the columns have a modulating burner.
Modulating burners can be controlled manually - with a special handle mounted on the housing - or through a microprocessor that maintains the set water temperature. The burners are made mainly of galvanized steel, as this material is optimal for performing the tasks set. It is inexpensive, durable, has a high melting temperature, normally tolerates frequent heating.
Types of combustion chamber and chimney
Combustion chambers in gas columns are of two types - open and closed. Their name reflects the essence:
- closed (turbine, fan) is a metal box in which a burner with a bell on top is installed to install a chimney;
- open (atmospheric) - this is actually the whole body of the column, since there is no isolated space, just a burner is installed in a certain place, there is a top with a bell on the top, to which the chimney is connected.
A different chimney is needed for different types of combustion chambers. In an open chamber, air intake takes place from the room, so an effective ventilation system, a normal air supply and an atmospheric chimney that opens into the ventilation duct is necessary. The closed chamber is equipped with a coaxial chimney (two pipes of different diameters, inserted one into the other), which is led through the wall to the street. At the same time, the combustion products are forced out, with the help of a fan through the inner tube, and oxygen flows directly to the burner through the external one.
Stable under normal conditions is a gas column with a closed combustion chamber, but there are drawbacks. The chimney can become frosty in winter, which causes the column to go out (its automation is extinguished, which controls the flue gas discharge). The second point - with a strong lateral wind, the air flow can blow out the flame. The gas supply is switched off by the same automation, but the situation is unpleasant. The third circumstance is that not all city authorities allow holes to wall in houses and pipes.
So, in this case, it is also difficult to say exactly which gas column is more difficult - it depends on many factors.
Heating of water occurs while it flows through the heat exchanger. It is a metal pipe installed above the burner. The form of the heat exchanger in the gas column is special - in the lower part there is a snake tube with fins, then a sheet of metal is mounted around it, over which a pipe is wound. Running along this long path, the water heats up from the heated metal.
Make heat exchangers from galvanized steel (the most budget option), stainless steel and copper. The best in terms of effective heat transfer is copper. They are the most economical, but also expensive. The most durable are stainless, but they have a much worse case with the transfer of heat. Which is better in this case - it's up to you. Choose the quality that is more important to you.
If you decide to buy a gas column with a copper heat exchanger, do not try to find a cheap model. In order to reduce the price, manufacturers use low-quality copper, and even pipes are made with thin walls. Such a heat exchanger will serve a warranty period, and then problems will start - it will leak.
If you remove the cover, you will see fistulas in the tubes, through which water drips. They are located for the most part on the outside of the pipe, just in the place where the condensate forms. At normal thickness of a pipe it is not terrible, but thin walls quickly corrodes. Such a heat exchanger with a leak is not necessary to change (it costs about 1/3 of the total price), it can be sealed. It will require a refractory solder with a melting point of about 200 ° C, a powerful soldering iron and a soldering flux. The technology of work is common - to clean the damaged area to clean metal, degrease, zaludit, solder.
How to determine the power
First of all, it is necessary to determine the capacity or capacity of the gas column. These are two interrelated characteristics that simply reflect the different characteristics of the unit. Performance - this is how many liters of water per minute the column can heat up, and the power - how much heat it can allocate. Some manufacturers indicate capacity, others - productivity, so you need to understand exactly what you need.
Let's first figure out what kind of performance you need a gas column. It depends on the number of consumers that need to be provided with warm water. There are rates of consumption for equipment of different types:
- kitchen sink, washbasin - 4 l / min;
- shower - 7-10 l / min.