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In our country, gas water heaters have been known for a long time and enjoy well-deserved trust. Their advantages include working on gas, which allows significant savings on the cost of hot water (as a result, it is cheaper economically than an electric water heater), independence from electricity supply, which is very convenient in rural areas, rather low equipment cost, wide selection of models by type and brand of manufacturer.
Modern gas water heaters are equipped with all kinds of control devices that allow users to be completely confident in the safety of the device.
Gas water heaters are divided into two types with respect to the method of operation: flow-through (columns) and storage (gas boilers). Each of them has undeniable advantages and disadvantages. Choose the best option only after a thorough acquaintance with the general principles of operation of each type of equipment.
Flow-through gas heaters
Features of gas water heaters of this type
The main requirement for the installation of water heaters of this type is the presence of permanent gas from the main networks. But it should be said that some manufacturers make water heaters that work well on liquefied gas, but the number of such models is extremely small.
Depending on the capacity of the unit, it can heat from 5 to 17 liters of water per minute - about as much as you can get by simply opening the central hot water tap.
Types of instantaneous water heaters
According to the ignition method, gas water heaters are of the following types:
- Piezo (the spark comes from the piezoelectric element);
- Electronic ignition (the spark comes from simple batteries);
- Hydrogenerators (the burner will ignite directly from the mini-turbine).
Experts note that gas water heaters with Pietro-ignition and constant burning of the pilot flame (most often they are low-end models of domestic production Neva, Vektor) ultimately consume more gas, respectively, higher bills for its payment than for models with automatic battery ignition or hydro.
In addition, many of the latest models are equipped with modulating burners, which regulate the operation of the device according to an increase or decrease in the amount of warm water consumed (or fluctuations in its temperature at the outlet).
Technical features of the functioning of instantaneous water heaters
Photo: techinfus.com
The main advantage of all types of gas columns is instantaneous heating of water - as soon as the burner flame comes on, the water that passes through the coil inside this gas column starts to heat up.Therefore, users can get without waiting for virtually unlimited amount of heated water.
Gas water heaters have power from 17 to 30 kW. If warm water is needed for one water intake point, for example, in the kitchen, then a column designed for 17-23 kW would be enough. In order to fully provide hot water and a bathroom, you need equipment with a capacity greater than 24 kW. The maximum value for gas heaters is 28-30 kW of power. From this indicator will depend on the amount of water heated per unit of time. The performance of different models of speakers can vary from 5 to 16 liters per minute. Regarding the orientation when choosing the optimal type of column according to the ratio of performance and flow of warm water:
- 10-11 liters per minute - enough only for kitchen needs or taking a shower;
- 13-14 liters per minute - allows you to simultaneously use heated water at two different points - for example, in the kitchen and bathroom;
- 14 liters per minute or more is the maximum comfort, it gives the opportunity to receive high temperature water at several points at once.
It is worth noting that the indicator of 24 kW is beyond the limit for electric water heaters - in order to ensure such efficiency of the unit, it would have to be connected to electricity by cable with the thickness of an adult finger.
The combustion chamber
Instantaneous water heaters have an open or closed combustion chamber. It is worth considering that heaters with a closed chamber are safer in operation. The reason is that they take air not from the room where they are directly based, but from the neighboring one, due to the presence of a conduit system. The models of heaters with an open chamber, on the contrary, consume air from the room where they are located - accordingly, if there is any malfunction in the system, gas can enter the room where the column is installed and this can lead to emergency consequences. Accordingly, columns with an open combustion chamber require special attention.
Advantages of instantaneous water heaters
Flow-through water heaters are quite elegant, do not take up much space and are economical in gas consumption. As a rule, after the warm water tap is opened, the automation switches on and opens the gas valve and ignites the burner. Now there are several ignition systems - with or without a wick on duty. The presence of a wick duty implies that it can be ignited on its own using a lighter, as was done many years ago. In systems without a wick on duty, the ignition of a gas burner occurs automatically using electronic or hydrodynamic ignition. The principles of operation of the hydrodynamic ignition system are quite simple and do not require additional energy sources - after the tap is opened, cold water flows into the column, while the water turns the turbine of the generator, which produces electricity in order to ignite the gas.
When installing a gas instantaneous water heater, it is important to consider that the distance between the unit and the tap should be no more than 6 meters, otherwise the waiting time for water will increase.
The most convenient to use are columns with modular burners, as they automatically regulate the flow of gas in an amount so that when the water pressure fluctuates at the outlet, its temperature is constant.
Accordingly, the gas column in the presence of the main gas is one of the most simple and economical options for getting hot water.
Accumulative gas heaters
Advantages of gas boilers
It should be noted that the majority of brands produce two versions of gas heater models regarding the type of combustion chamber: closed and open. With the closed type of the combustion chamber, the thrust is carried out forcibly, with the open type - in the natural.
Accumulative gas heaters with forced pitch are more modern and convenient to use, do not require additional air flow in the room to support the combustion processes, their installation is simpler and cheaper, since they do not need to install a traditional chimney. But at the same time there is one drawback - they are more expensive than gas water heaters with an open type of combustion chamber.
Technical characteristics of gas boilers
Boilers, which are intended for domestic needs, respectively, have a small displacement, are mounted directly on the wall, and gas boilers of semi-industrial and industrial type are installed on the floor due to large size and large weight. Wall-mounted water heaters have tanks of up to 120 liters, this amount of water is enough for domestic needs of an ordinary family of 3-4 people. The volume of the tank floor heaters can range from 150 to 20,000 liters.
The undoubted advantage of boiler water heaters is the presence of a reserve of hot water - it exists thanks to a storage tank. Also, water heaters of this type have minimal heat loss - almost all models have a special heat-insulating layer consisting of poly-polyurethane or mineral wool, which prevents water from cooling rapidly.
Accumulative gas heaters are completely safe - most models have sensors of thrust and the presence of flame. In the event of a fault, they block the gas supply to the unit.
Also, storage heaters are excellent for domestic use in large families - it is possible to connect equipment to several water intake points simultaneously and use hot water in the bathroom and in the kitchen at once.
Regarding the important characteristics of boilers, it is worth noting that due to the gradual heating of the liquid in the tank, storage water heaters have relatively low power - from 4.2 to 9 kW. The higher this figure, the more powerful the unit and the faster the water is heated. It is also worth noting that with equal volumes of the storage tank, the gas water heater heats the water faster than the electric one. In addition, it does not depend on outages, restrictions or power fluctuations.
Choice of gas water heaters
The most valuable advantage of water heaters is the independence from interruptions in the supply of warm water by a centralized hot water system; it is not turned off in the event of accidents, interruptions or maintenance. Undoubtedly, it is important that the user independently selects the desired water temperature (from 200 to 600C). In addition, it often happens that the temperature of warm water in the central hot water supply system does not always comply with the standards for temperature — hot water flows through the pipes, not hot.
Additionally, it is worth noting that the amount of payments for water heated with a gas water heater, in any case, will be lower than the tariff at a centralized supply.
When purchasing a gas water heater, you should pay close attention to its technical characteristics - if the power is less than necessary for use, there will always be a lack of hot water (water will be lower), with constant overloads the equipment will quickly fail. Also, if the power of the unit is close enough for the planned consumption, the water heater may also soon break down - with constant operation at maximum power and at high speeds, the heating elements will soon fail.
Comparative technical characteristics of gas water heaters
The need for automatic regulation of the flame in the columns
Modern columns have a traditional or modular burner. In the design of a traditional burner, the heating element is constantly operating at a given power, the water temperature will change if the pressure of the water flow decreases. You must manually reduce or increase power depending on your needs. Columns with a modulating burner do not need to carry out these manipulations, because there is automatic regulation, special sensors work that monitor the liquid head, the gas pressure, and the power is adjusted accordingly, which allows the user to maintain the temperature.
Types of heat exchanger material in gas heater designs
As part of the water heaters, one of the most important components is the heat exchanger. Therefore, when buying, you need to pay attention to what material it is made of. Most often it is made of copper - this material is durable, not subject to corrosion, respectively, the unit will faithfully serve a long time. But copper has a weak side - intolerance to the action of too high temperatures, in this case, sensors are needed that will not allow the element to overheat.
The heat exchanger can be made from copper - it will be resistant to high temperature, but its service life is relatively short - on the strength of a couple of years. therefore, it is not surprising that the cost of a column with a steel heat exchanger will be lower than with a copper one.
Installation of gas water heaters
Initially, any gas equipment requires special attention and serious approach during installation work. In order to provide services for the installation and maintenance of gas units in our country, there is a mandatory certification of all services that are engaged in this area of work. Their activities are regulated by the regulatory documents of the state standard. When concluding a contract for the installation of gas units, you should carefully review all the certificates and documents of the service, get customer feedback (best of all, if they are friends, neighbors, relatives who have already hired specialists of this service at least several months ago).
There are several different options for connecting gas water heaters - using a flexible liner, metal-plastic or propylene pipes. For hot water, only propylene or metal-plastic pipes are used, as the flexible liner will quickly fail.
If a wall mounted gas water heater is mounted, then complete with it are anchors for mounting the unit on the wall. You should also take into account the quality of water - in the case when the tap water is hard, a precipitate will form when heated, respectively, it is advisable to put a filter on the outlet of the hot water so that there is no sediment in the pipes. Additionally, you must consider that the formation of scale reduces the efficiency of the water heater and its service life. In order to prevent its occurrence, you should contact the specialists who will periodically clean the gas water heater pipes from the resulting lime scale, it is impossible to perform this procedure yourself.
Installation of a gas heater of any type should be entrusted to specialists: firstly, it ensures safety and the absence of emergency situations, secondly, it is a guarantee for the water heater itself, because in the case of self-installation of equipment, the warranty on the product is automatically removed.
Technical requirements for the installation of gas heaters
In all private houses and apartments when installing columns, it is necessary to know the initial security requirements.
If a column with an open combustion chamber, then the cubic capacity of the floor area should be at least 8 square meters. If the water heater with a closed chamber, then the area of the room should be at least 6 square meters. The height of the ceiling in the room should be at least 2.2 meters and must have natural ventilation. If the model is a column with an open combustion chamber, then it is necessary to provide for a constant influx of fresh air into the room, for example, through a window or a slightly opened door.
Most often geysers are installed as close as possible to the mixers (water intake points). In the apartments, they are predominantly mounted in the kitchen.
For gas instantaneous water heaters that have an open chamber, the products of combustion must be removed by means of a natural draft flue. This chimney should be made of acid-resistant steel, because in the process of oxidation will form aggressive acids that cause corrosion on a simple, unprotected metal. In models with a closed chamber, the products of combustion must be removed through a coaxial channel.
findings
Gas water heaters are great for heating hot water. They are used for domestic and industrial needs in the presence of the main or liquefied gas. There is a wide choice of types of heaters - the range of both domestic and foreign manufacturers of this equipment is presented on the market, each of which has a wide model range. Among their undoubted advantages are independence from voltage surges in the electrical network (which happens quite often in our conditions, especially outside the city), cost effectiveness and autonomous provision of a house or apartment with hot water. It is worth buying gas heaters only in a new state, checking the presence of all certificates and permits - in case of a fake, the price of inattention may be too high, because it may entail a dangerous situation. The installation of the equipment should also be entrusted to specialists, having previously read their licenses and work permits, because in the case of installation of equipment by non-specialized workers, the warranty for the purchased goods automatically burns.
