Gas water heater with a closed combustion chamber: flow-through, chimneyless, coaxial

The main advantages of chimneyless gas heaters

Chimneyless geysers are good for many reasons. Firstly, they can be installed without adding a chimney in the traditional sense. Secondly, such equipment has a fairly high efficiency. This is due to forced air injection. Thirdly, the unit has a closed combustion chamber, which eliminates the increase in room temperature, which is especially important when operating the equipment in the summer.

However, chimneyless geysers are chosen not only for the reasons described above. They are also good because they do not burn up the oxygen in the house with their work, since they take air for functioning from the street. In addition, the housing of such devices is almost completely closed, which significantly reduces the risk of combustion products getting inside.

Differences between a chimneyless device and a conventional one

A significant feature of the design of the device is a closed chamber into which street air is supplied using a fan (turbine). Traditional water heating devices use room air during burner operation through an opening located at the bottom of the column.

Any device operating on gas emits hazardous substances that must be removed outside. The turbo column is no exception, only here, instead of the usual chimney, a horizontal pipe (coaxial) is used, led out into the street through a hole in the wall. gas-type water heater with a closed firebox has several more properties:

• for complete combustion of gas, the turbine delivers air from the street using a coaxial double-walled (double-circuit) chimney, through which toxic gases are discharged outside;
• the device is equipped with multi-stage and modulating burners that can change the power and intensity of heating;
• there is no regularly burning pilot wick, piezo ignition button or traditional batteries to start the water heating process;
• a gas water heater
  without a chimney does not completely stop operating in automatic mode from the moment it is ignited until it is turned off;
• the electronic unit (controller) changes the air and gas flow in good accordance with the appropriate heating mode;
• turbocharged devices operate from the electrical network.

In most cases, gas-type with a coaxial chimney are equipped with an electric ignition system with electrodes to produce a spark. But not all types of columns use a mechanical hydrogenerator, which generates energy from a moving stream of water. Based on the properties of the devices, it is clear that they are equipped with a large number of purposes that increase comfort and operational safety.

Main disadvantages

Before you purchase the equipment described in the article, you need to familiarize yourself with its main disadvantages, among them the following should be highlighted:

• energy dependence;
• noisiness;
• high cost;
• the need to obtain approval;
• condensation formation inside the outlet pipe.

If you like chimneyless geysers, then before purchasing one of the models you need to become more familiar with the disadvantages of such equipment. For example, many consumers are put off by energy dependence, because the design’s fan is powered by electricity. If it is turned off, the operation of the turbocharged column will be impossible.

You may also be put off by the fact that the equipment fan is quite noisy. Such devices are more expensive than traditional models. On average, the cost of a turbocharged unit is approximately 17,000 rubles. In order to install such a column, approval will be required from the organizations that are responsible for the supply of natural gas. You can’t do it without the permission of the neighbors who live on the floor above. Installing a column requires that the pipe be installed on the façade of the building, which may be prohibited by the architectural control service.

Disadvantages when using the device

The disadvantage of a coaxial geyser is its energy dependence. If there is a power outage, there will be no hot water. You will need to use an electric generator or a reliable uninterruptible power supply. Other negative aspects of these devices:

1. A coaxial gas unit is almost twice as expensive as an atmospheric one. But when comparing the purchase and installation in a complex, a coaxial chimney will cost much less than making it out of brick or installing an insulated sandwich.
2. Fan noise is heard on some speaker models.
3. It is better to entrust cleaning of the device to a specialist. Modern equipment has a complex structure, so trying to find the malfunction and fix it yourself is not recommended.

To install this type of unit, permission from the organization supplying natural gas is required. You should also notify neighbors that a chimney exhaust will be installed on the facade of the house.

Device

The design of devices with forced exhaust follows the design of an instantaneous water heater. Water is heated using the energy of burned gas - natural or liquefied. The liquid is supplied from a water pipe: cold water, heated by a gas burner, enters the water intake point. When the tap is opened, the burner lights up and already heated liquid flows from it. The device has a sealed, closed combustion chamber. A coaxial pipe extends from the chamber and communicates with the street.

The coaxial pipe design has two channels: external and internal. The first serves to supply air to the combustion chamber, the second to remove smoke. What is the advantage of such a technical solution? In a room you have to make only one hole in the wall, and not two - separately for input and output. A prerequisite for the operation of a turbocharged water heater is the presence of a fan that directs exhaust gases into a coaxial pipe.

Control systems

Instantaneous chimneyless water heaters may differ in burner type:

1. With automatic power control - automatic burners maintain a given combustion power, so the outlet stream is consistently hot, regardless of the pressure in the pipes.
2. With manual adjustment - in this case, the degree of heating can be adjusted with a mechanical switch. But temperature is not a constant value: it is influenced by atmospheric conditions, the temperature of the incoming flow and the pressure in the gas pipeline.

Ignition type

Turbo system speakers may have:

• Electric ignition: the “start” command is given by a sensor that is triggered when the hot water tap opens; power source - batteries or mains. Its advantage is that there is no constantly burning pilot light, which means that gas is not wasted.
• Piezo ignition: a spark appears at the moment of mechanical action on the ignition button. The downside is that the pilot light is constantly on.
• Hydro Turbine Ignition: The built-in generator generates electricity using the energy of the water flow passing through it. Such devices do not require batteries or electricity.

  

Boiler column with a closed chamber

This is a type of gas device, which is a reservoir in which water is heated, and then distributed through pipe lines to water points. The water in the tank is constantly hot, and not at the moment the hot water tap is opened, as when using a flow-through heat generator. The chimneyless column works on the following principle: when the temperature in the tank drops, the temperature sensor sends a signal to the burner device to turn on. During operation of the burner, hot air enters the flame tube, surrounded by water, and transfers heat to it. As soon as the water heats up to the set mode, the burner turns off.

The container of the device is equipped with thermal insulation, so, like a thermos, it can maintain temperature for a long time. You can always use hot water instantly and in the required volume. The capacity of the storage device tank is different for all models, ranging from 10 to 500 liters. The body is made of steel, covered with enamel or porcelain glass. The main advantage of the boiler is the use of a large volume of hot water even when the water supply is completely turned off.

But, like any technological design, a turbocharged water heater has a drawback - hot water remains in the gap between the DHW valve and the tank, which then cools. Therefore, the user, having opened the tap, has to wait until the cold water comes out.

This problem is solved by using a circulation unit consisting of a small pump that is connected by a small diameter pipe to a system of pipes leading to the end points. Using a pump, the remaining unused water is pumped back into the tank, thereby preventing it from cooling down.

What to consider when choosing a turbo dispenser

When buying a turbocharged water heater, pay attention to the following parameters:

1. Thermal power - take the middle option. Don’t chase powerful modifications: they cost much more and don’t fully utilize your resource.
2. Performance - this parameter indicates the volume of liquid heated to a certain temperature per unit time. For comfortable use, 10-11 l/min is enough.
3. Each model has its own limitation on the pressure in the water pipes - if it reaches a value below a certain limit, the device simply will not turn on.
4. Fuel used - there are devices that can operate on two types of gas: natural and liquefied.
5. Type of chimney - for example, the Neva column may have a horizontal or vertical chimney outlet.
6. Type of ignition - for example, for Oasis speakers, ignition can be electronic or from a piezoelectric element.

   

How to determine the required parameters

User comfort and resource savings depend on the correct choice of technical characteristics of gas equipment. The buyer can independently determine the required parameters:

1. Power. As it increases, the volume of hot flow increases. How can I find out the approximate power level needed? Divide by 2 the value given in the device passport. The resulting result is the flow rate of liquid heated to 30°C per minute. If the value is 20 kW, the device will be able to heat approximately 10 l/min. Knowing the needs of the family, each user will be able to decide whether such opportunities suit him.
2. Performance. We are talking about the volume of heated liquid produced by the heater per unit of time. If it is indicated: 12 l/min up to 25°C, then the temperature of the source flow should be added to this value. So, if the cold water temperature is 10°C, then in a minute the device will heat it to 35°C (25 + 10) at a flow rate of 12 l/min.

Important! It is believed that a capacity of 5.5 l/min is sufficient for one water intake point - washbasin, shower or sink.

Installation

Self-installation of gas water heaters is excluded - this should be done by specialists from the relevant services. But you can connect to the water supply yourself. You will need couplings to ensure the tightness of the connections, and a tee - it is necessary to provide hot and cold water. The user can also install a coaxial chimney himself.

Gas-type water heating device without chimney

The working principle of the geyser is to release the energy of the combustion gas, which is used to heat water, and it does not require any additional chimney. For such a device, it is most optimal to use liquefied or network gas from cylinders or an intra-house network.

This column

does not need the usual vertical chimney; it has a different system for removing gaseous, liquid and solid substances.
In such a device, the firebox is considered sealed , and the removal of gaseous, liquid and solid substances is carried out through a coaxial chimney
, which is discharged directly into the street through the wall. You need to immediately make a hole in one of the walls when installing a turbocharged column. This device has a built-in fan that directs gaseous, liquid and solid substances in the required direction.

Through the inner part of the coaxial pipe, carbon monoxide is discharged to the street, and fresh air, which is intended for the combustion process, enters through the external channel.

This column

It is also convenient in that it does not dry out the air in the room and does not require additional air flow to support combustion.
Due to the fact that there is no need to install a separate vertical chimney, it is possible to significantly save on the purchase of materials and installation work.
When selecting a turbocharged gas water heater, the following characteristics are first taken into account:

• productivity;
• type of ignition;
• power;
• security parameter;
• types of burners.

An important factor is the method of placing the device - horizontal or vertical, due to the fact that the combustion product exhaust system in a wide variety of columns is designed differently.

Recommendations when choosing

It is impossible to give any definite advice regarding the place of purchase of a gas appliance. You need to focus on stores known for quality of service, a varied assortment, and the presence of decent models.

Specialized plumbing and heating equipment stores offer a large selection of products, the characteristics of which can be seen in person and the appearance of the column can be assessed. Purchasing through an online store also has its advantages - the ability to exchange and return goods within two weeks without specifying the reason, a huge selection, ordering a rare model, reading reviews from other customers.

The Neva gas water heater with a closed combustion chamber is popular. This equipment is characterized by flow-through heating of water, the use of liquefied gas, and the ability to connect to bottled gas. Based on operating practice, it is known that using this device you can obtain 6 liters of hot water per minute. The flow column is equipped with sensors and timers that are responsible for the high-quality functioning of the device. Has a power of 9 kW.

When purchasing a gas water heater, first of all, you should make sure that there is a decent security system for comfortable use of the equipment. It must be equipped with sensors that monitor flame, overheating and backdraft of the chimney. You can choose any ignition option based on your preferences and wishes.

How to choose a gas-type water heater that does not require a chimney?

Types of columns without chimney

Everyone needs hot water, in any weather and whenever. Gas-type water heaters can provide us with such an important event for our everyday comfort.

(columns), thanks to which, regardless of the central water supplier, we will begin to use hot water.

Turbocharged column

- a device that will be the best option in situations where there is a need to provide hot water in an apartment, a house of several floors - where the presence of a chimney exhaust is either unrealistic or was not calculated by the developer.

Plus, this type of gas-powered dispenser is also called a chimneyless turbocharged dispenser

may be the best solution if you need to save as much space as possible in your home, on your summer cottage, or in a room for industrial needs.

Column

without a chimney - an original engineering design, which, by introducing a modern type of firebox, and a radical change in the system for removing gas waste products, created a new type of gas-powered, multifunctional dispensers.

Roda JSD20-T1

A popular middle column in catalogs from a well-known German manufacturer of household appliances. The average price in Russian online catalogs fluctuates around 11-12 thousand rubles.

Characteristics

The overall product rating is 4.5. An excellent model, affordable, reliable, and very easy to operate. There is one significant drawback - it does not work on propane.

Reviews from real users

There is a good tradition: before choosing a turbocharged speaker, it doesn’t hurt to read the user reviews left on thematic forms. We have made a selection of statements from real people about water heaters from different manufacturers:

1. Nikolay, Vladimir, Russian Federation. Six months ago I installed an Ariston MARCO POLO GI7S 11L FFI turbo dispenser. The general conclusion is that the device is worthy and has never let you down. Definitely an A for appearance. But there is one strange thing: heating a given amount of water. I don’t understand this function - either the heating should turn off when the bath is full, or it should turn it off by a signal. I was a little mistaken about the power, in my case I had to take Ariston GI7S 16L, otherwise 11 liters per minute is sometimes not enough.
2. Sergey, Moscow, Russian Federation. I made a mistake by buying a Bosch WTD15 AME speaker with a turbine. I didn’t like it already during the installation and connection process. Some of the pipes are flimsy, it’s scary to tighten the nuts. The first time I opened the water, the connection leaked, I had to unscrew it and change the rubber ring. I don’t know how to use it yet, I haven’t turned it on yet.
3. Alexey, Dnepr, Ukraine. We haven’t had hot water in our city for a long time, most people installed boilers, but I solved the boiler. It was forbidden to connect a chimney to the ventilation, so I took a Junkers chimneyless unit (German brand, Portuguese assembly). Although I ran around for all sorts of permits, I’m generally satisfied; I don’t have to wait for the water in the tank to heat up. I live on the top floor, there were no problems with the chimney. The gas workers said that it would be more problematic to remove the pipe on other floors.
4. Mikhail, Kursk, Russian Federation. Proton exchanged his ancient speaker for a Roda JSD20-T1, a neighbor installed one and praised it. Everything would be fine, but our pressure jumps in the pipe, as soon as I open two mixers at once, the heater turns off, and then lights up again. The gas workers came twice, checked and said that everything was fine with the device. Now we are trying to get the hang of opening the taps one at a time, but otherwise there are no questions, the water heats up normally.

Colorfully designed water heaters look impressive.
In general, reviews of turbocharged gas water heaters are positive, although there are many small nuances that cause inconvenience. Much less negativity is expressed, and most of these reviews are related to the fact that they did not like the product initially or that the equipment could not be installed and connected independently. The latter is quite natural, because in addition to having plumbing skills, you need to be familiar with electrical engineering and know that many imported household appliances are sensitive to incorrect phase connections.

For reference. Some apartment owners who have used gas water heaters before do not like pressurized units for the sole reason that the combustion process is not visible in them. This gives rise to some psychological discomfort and groundless prejudice towards such products. Good news: you can find turbo units with a viewing window on sale, for example, the Chinese water heater Selena SWH 20 SE1.

Lemax Turbo-24

Lemax Turbo-24
Also a well-known model from catalogs. The production is a Russian-Chinese joint venture, thanks to which the electronics are quite decent and the price is affordable - from 15 thousand rubles.

Characteristics

Rating - 4. Good performance, adapted to Russian networks, but assembly is not always perfect.

WERT 10LT white

WERT 10LT white
An ultra-budget option for the home, it costs only 8 thousand rubles, which is cheaper than many speakers with an open chamber.

Characteristics

Rating - 3. Chinese assembly in the worst sense of the word. The turbine is noisy, breaks down, and periodically produces the wrong water temperature. But it's cheap.

Purpose and principle of operation

The exhaust pipe for the geyser - air duct - ensures the removal of combustion products that are produced during the operation of the heating device. Due to the difference in temperature and density, the flow of waste substances is directed upward through a sealed channel and discharged outside. Due to the pressure difference in the gas outlet, a natural draft is formed, and air from the room, necessary for continuous combustion, enters the firebox.

The chimney pipe for a gas water heater is a sealed line that is constructed between the combustion chamber and the entrance to the exhaust shaft of a multi-story building. In a private house, the gas exhaust channel is led directly outside through the wall or roof of the building.

Vatti MR11-N

Vatti MR11-N
Miniature and very low-power speaker. Prices - from 5 thousand rubles.

Characteristics

Rating: 2. Heated washbasin. Any theoretical advantages end with performance: the device can hardly serve one mixer.

When is it impossible to install a speaker in an apartment?

Before installing a gas water heater in an apartment for the first time, you must obtain permission from the gas supply company. To do this, you must perform the following sequence of actions:

• collect documents: floor plan, extract confirming ownership of the apartment, installation project, technical passport for the gas device;
• write an application to the gas supply company to provide official permission for installation and attach the relevant documents;
• The supplier will consider the application for several weeks and then give permission for installation;
• If the gas supply company refuses to obtain a permit, it issues a paper explaining the reason for the refusal.

The reasons why installing a geyser in an apartment is prohibited may vary. Sometimes it happens that it is enough to find another place to place the device and redo the project. In some cases, installation is strictly prohibited. The column cannot be installed in the following cases:

• the apartment building has more than 11 floors;
• there is a redevelopment - the kitchen is combined with a living room or bedroom;
• It is planned to hang the device on a load-bearing wall.
• the premises do not meet regulatory requirements.

After receiving permission to install a geyser in the apartment, you can call the specialists who drew up the project to implement it.

Superflame SF0322

Superflame SF0322
“Quality Chinese”, average in price - about 10 thousand rubles.

Characteristics

Rating: 4. Average model.

Kinds

To choose a safe gas water heater for an apartment or house, you need to understand the appropriate type of equipment.

With open camera

Disadvantages of atmospheric geysers:

• High gas consumption.
• High technical requirements for installation and installation location.
• Low efficiency.
• It is necessary to have a chimney of the appropriate configuration, length, and size.
• The need to organize a high-quality ventilation system.
• Fire hazard.
• Risk of carbon monoxide poisoning if the system fails or the burner self-extinguishes.

With closed camera

These models are also called turbocharged.

The principle of their operation is somewhat different:

• The combustion chamber is sealed.
• Air intake is carried out not from the room, but from the street.
• The design has one or more fans that pump air for gas combustion and facilitate faster removal of waste combustion products.

Pros of turbocharged models:

• Economical gas consumption and better, complete combustion. When installing a water heater with a closed combustion chamber, gas consumption is reduced on average by ⅓ compared to atmospheric models.
• High efficiency.
• A high level of safety not only in terms of removal of combustion products, but also protection against overheating of the unit.
• Possibility of using a coaxial chimney.
• A fully automated system operation process that does not require frequent user control.

Minuses:

• Energy dependence. Typically, such geysers are also connected to the electrical network.
• There is background noise when the system is operating, so you need to think carefully about the placement location.

When choosing between the options described above, it is definitely better to choose a gas water heater with a closed combustion chamber, especially if you plan to install it in an apartment.

With piezometric ignition

Models with piezometric ignition have long appeared on the market, displacing equipment with manual ignition, proving to be simpler, more convenient, and safer to maintain.

Geysers of this type are equipped with a button on the front panel, pressing which activates the piezometric element. It provides a spark that ignites the pilot light. Then everything functions automatically - the gas supply valve opens, the water dispenser lights up, the water is heated and supplied to the water intake point.

With electric ignition

These are the most reliable and safe automatic gas water heaters of the latest generation. The ignition system operates from a set of pairs of batteries, which provide the charge necessary to produce a spark. When choosing such a model, you don’t even need to press any buttons - just open the water tap, and ignition is carried out autonomously, as well as stopping the burner from burning.

Semi-turbo gas water heaters Termet

Polish-made equipment is quite widely represented on the market. There is a stable demand for these speakers.

Model Termet Aquacomfort Turbo G19-03

Termet Aqua Comfort turbo G19-03

The turbocharged one is equipped with electric ignition equipment. Thermal power is 19.2 kW, the provided hot feed flow is 11 l/min (temperature 25 degrees). Such a column can operate on natural and liquefied gas.

The average cost is 6-7 thousand rubles.

Turbocharged speakers BOSCH

Equipment of this class belongs to an expensive price category.

Model BOSCH Therm 8000 S WTD 27 AME

The products of this brand are highly reliable and of excellent quality. The column can provide a flow rate of up to 27 l/min (25 degrees), the thermal power is 45 kW.

Such a model will cost the buyer 100-110 thousand rubles.

It is advisable to purchase such a water heater to provide hot water to restaurants and bars. In general, the main scope of application is professional use.

Turbocharged geysers are the optimal choice of equipment for hot water supply in the absence of chimneys.

“Selecting and installing a pump in the heating system - is there a need? Induction water heater (boiler) - design and principle of operation »

Specifics of gas-type water heaters without chimney

Residents of apartments or privatized houses cannot do without hot water. You just need to decide which device heats cold water best. Turbocharged column

very convenient to use and provides the hot water needs of all residents who use it. In some cases, it is most optimal to use gas boilers, in others, flow-type water heaters are perfect.

For multi-apartment high-rise buildings, the most comfortable and functional solution would be to use a turbocharged dispenser.

Models with capacity up to 8 l/min

#1

Bosch WTD 12 AME

Reliable and powerful model from a manufacturer with an impeccable reputation

Expert rating:98/ 100

The modification of the Therm 4000 S series from the Bosch brand is distinguished by its standard dimensions, thanks to which the column can be placed even in a small room.

Despite its relatively modest performance, a water heater designed for one water intake point is quite powerful. Therefore, with it, the water almost instantly heats up to 60 degrees. It is also convenient that the Bosch Bosch WTD 12 AME model operates without interruption even with low inlet water pressure: the unit only needs 0.1 atm to start the heating process.

Gas consumption is also pleasing: this column consumes 2.1 cubic meters. m/h when connected to a common gas pipeline and 1.7 cubic meters. m/h when operating from a cylinder. Fuel saving is also facilitated by electric ignition, which turns on the burner only when the tap is opened.

Specifications:

• power – 20.8 kW;
• productivity – 8 l/min;
• minimum/maximum water pressure – 0.1/12 atm;
• control type – electronic;
• dimensions (WxHxD, mm) – 300x568x170.

Bosch WTD 12 AME can be called the optimal model for homes with low pressure in the water supply. And working on liquefied gas from a cylinder allows you to use the equipment even where gasification has not yet been carried out.

Advantages

• Economical
• Control of temperature fluctuations down to 1 degree
• Excellent power
• Heating water up to 60 degrees
• Trouble-free operation at low water pressure

Flaws

• Price

#2

Oasis B-12W

Compact and inexpensive speaker for very small kitchens

Expert rating:96/ 100

The budget speaker from Oasis has low performance, but fully compensates for it with its dimensions and low weight of 4.2 kg. It is one of the most compact in height and depth, making it suitable for small rooms or even niches. Electric ignition is carried out using batteries, which makes the device operate completely independent of the mains.

A bonus is the operation under conditions of low pressure in the gas pipeline. To start heating the model normally, a pressure of 0.02 MPa is sufficient. At the same time, the column maintains high efficiency - more than 90%. The manufacturer provides the ability to limit the maximum water heating temperature, which allows you to save gas.

Specifications:

• power – 11 kW;
• productivity – 5 l/min;
• minimum/maximum water pressure – 0.2/8 atm;
• control type – mechanical;
• Dimensions (WxHxD, mm) – 290x370x120.

Oasis B-12W is installed vertically with bottom connection. The multi-level security system makes operation as reliable as possible, which is especially important for families with children.

Advantages

• Compact and light weight
• Undemanding to pressure in the gas pipeline
• High efficiency
• Reasonable price
• Availability of display and thermometer

Flaws

• The first malfunctions may appear after a couple of years of operation.

Operation of the unit with supercharging

All gas flow structures operate on the same principle: when the hot water valve in the apparatus is opened, the burner lights up under flow pressure and begins to warm the liquid circulating through the heat exchanger. In a turbocharged device, the process occurs a little differently:

1. While in standby mode, the device is connected to the electrical network. There is no combustion process in the chamber, since there is no ignition wick.
2. When you open the water tap, the flow meter and membrane fabrics of the water unit are turned on. Under its influence, a valve is activated, allowing gas access to the burner mechanism.
3. The controller sends a command to the electrodes located next to the burner, a spark appears that ignites the gas. The meter reacts to the flame and signals to the control unit, the spark formation ends, and at the same time the turbine is turned on, pumping air.
4. When the DHW tap is closed, the gas supply ends, the burner goes out, so the water heating process is completed.

Thanks to the improved design, the efficiency of a chimneyless unit can reach 88–90%, while that of an ordinary atmospheric unit is 84%. Effectiveness is determined by such functions:

• precise dosing of incoming gas and air needed for the combustion process;
• maintaining the required temperature regime is a function that allows you to save gas, since the consumption of excessive heating is eliminated;
• preheating of the street air flow with a coaxial chimney.

This function is the most effective, allowing you to replace the heat that is carried away with gas toxins. Cool air, entering through the same pipe, only in a different plane, takes heat from the oncoming smoke waste through the steel wall of the inner pipe.

Column

gas with a coaxial type chimney is equipped with safety features. They work in situations like this:

• lack of draft in the chimney due to the cessation of operation of the turbine, which stopped during a power outage;
• the burner went out spontaneously;
• reduced water consumption;
• controller function failure.

• lack of draft in the chimney due to the cessation of operation of the turbine, which stopped during a power outage;
• the burner went out spontaneously;
• reduced water consumption;
• controller function failure.

In any case, the gas

valve that shuts off fuel. It also reacts to power outages, burner extinguishing and pressure surges in the gas pipeline, without controller intervention.

Models with a capacity of 10 l/min

#1

Roda JSD20-T1

Practical performance speaker in an ultra-thin design

Expert rating:99/ 100

Among gas water heaters operating without a chimney, the Chinese-made model stands out for its more compact depth, which ensures fairly flexible installation. Roda JSD20-T1 is equipped with a gas control system and makes it possible to limit the water heating temperature.

A useful feature of the model is a reliable frost protection system. As soon as the heat exchanger temperature drops below +5 degrees, the built-in ceramic heating elements automatically begin heating the water in the tubes.

The model is maximally adapted to work in conditions of low gas pressure and is extremely sensitive to the opening of a water tap. In addition to the integral gas control, the water heater is equipped with protection against overheating and exceeding the permissible water pressure.

Specifications:

• power – 20 kW;
• productivity – 10 l/min;
• minimum/maximum water pressure – 0.3/8 atm;
• control type – mechanical;
• dimensions (WxHxD, mm) – 330x515x140.

The modification is extremely protected from pressure or temperature surges, has internal control systems, and is therefore optimal for installation in problem housing with old communal communications.

Advantages

• Adapted to difficult operating conditions
• Easy control and setup
• Ergonomic LED display
• Affordable price for the class

Flaws

• Heat exchanger with a short service life

#2

Bosch WTD 15 AME

High-quality water heater with the ability to operate on liquefied gas

Expert rating:98/ 100

Another model from Bosch in the review, capable of providing hot water to homes not connected to the gas supply network. It features impeccable build quality and reliable operation. In addition to limiting the maximum heating of the carrier, the column has a flame modulation system. The option allows you to regulate the strength of the fire, strictly maintaining the set water temperature.

The heat exchanger itself is made of high-quality copper without unwanted impurities, resistant to burnout. The model is assembled conscientiously and is practically not subject to breakdowns.

Specifications:

• power – 25.4 kW;
• productivity – 10 l/min;
• minimum/maximum water pressure – 0.3/12 atm;
• control type – electronic;
• dimensions (WxHxD, mm) – 300x568x170.

Bosch WTD 15 AME belongs to the Therm 4000 S series. It is characterized by economical consumption of blue fuel and has an impressive design. We can recommend this model to consumers who are willing to overpay for reliability, uninterrupted operation and a decent level of equipment safety.

Advantages

• Multi-level equipment protection
• High power ratings
• Stylish design
• High-quality assembly without backlashes or cracks
• Fast heating of water up to 60 degrees

Flaws

• High price

#3

Superflame SF0420T bal (turbo)

The most suitable model for domestic conditions

Expert rating:96/ 100

The SF0420T bal turbocharged water heater is just the type of gas water heater operating without an exhaust hood, which is ideal for working with unstable water pressure. After all, the Superflame brand itself was registered in Spain; most of the brand’s products are aimed at Europe. But after entering the Russian market, the manufacturer improved the speakers to suit the realities of operating conditions in the CIS countries.

Advantages and disadvantages of gas instantaneous water heaters

As we have already said, gas instantaneous water heaters have a number of advantages and disadvantages. In some ways, their use is completely justified, but in some cases it is desirable to use electrical equipment. Key benefits:

• Cost-effective – using gas water heaters allows you to spend less money on preparing hot water. The savings are most noticeable with intensive use;
• Powerful electrical wiring is not needed - electric instantaneous water heaters, if normal performance is required, will require a separate supply line. You also need good grounding;
• They can work in non-gasified premises - for this you need to purchase a model with the ability to be powered from a gas cylinder.

There are also a number of disadvantages:

• Complexity of installation and connection - it is advisable to have a specialist do this;
• The need for regular maintenance - you have to pay for this separately;
• Possible gas leaks - the high explosiveness of natural gas makes it necessary to carefully monitor gas equipment. For example, a column with piezo ignition needs to be extinguished when no one is at home;
• It takes time to heat up the water - the same electric storage water heaters supply hot water almost immediately.

Despite certain disadvantages, it is customary to install gas instantaneous water heaters in gasified houses - they are economical and can provide hot water to several water supply points at once.

The disadvantage of gas instantaneous water heaters is that their use in some buildings is simply prohibited. Also, they cannot be installed in modern new buildings where there is no gas supply.

Advantages of chimneyless water heaters

As we have already found out above, there is no gas water heater without a chimney, and in the case of turbocharged units it is structurally simplified. This is the main advantage of forced-air water heaters, thanks to which they can be installed in any private house or apartment. It is enough just to lay the chimney horizontally along the shortest path from the apparatus to the outer wall and take it outside by making a hole.

This is what a coaxial chimney looks like when laid through an external wall

For reference. If necessary, a coaxial pipe can also be installed on the roof of a private house by laying it vertically inside a finished shaft or directly through ceilings lined with non-combustible materials. Details about connecting chimney pipes to geysers are presented in this article.

Now we list other advantages of “flueless” gas heaters:

1. Increased efficiency and cost-effectiveness compared to traditional household appliances for heating hot water;
2. Thanks to the closed chamber, the penetration of harmful gases and unpleasant odors into the premises is excluded;
3. To install a water heater, it is enough to organize regular supply and exhaust ventilation, since it is impossible to do without a hood completely. But you don’t have to worry about how to arrange a supply of fresh air for combustion in the room.
4. The high degree of automation of the turbocharged column makes it very convenient to use.
5. The ability to use not only natural but also liquefied gas as an energy carrier. True, this requires a special hood located in the lower zone of the room (propane is heavier than air and spreads along the floor).

The water heater is closed on all sides, with a pipe for connecting a coaxial pipe coming out from above, and fittings for water and gas from below
. In addition to several sensors responsible for the safety and maintenance of water temperature for domestic hot water needs, the forced-air dispensers are equipped with a heat exchanger antifreeze system. The principle is simple: when the temperature in the room drops below zero, the electric heating element will automatically turn on, heating the heat exchanger and preventing the water from freezing.

The anti-freeze function in a turbocharged column may be useful in case of emergency shutdown of the heating system in winter. It will keep expensive equipment from defrosting until the owners take measures to heat the house. True, it is unknown what will happen to cold water pipelines if they are made of steel or polypropylene.

For reference. Not so long ago, condensing geysers appeared on sale, working even more efficiently than turbocharged ones. An example is the BOSCH WTD 27AME THERM 8000 S with a power of 48 kW and a capacity of 27 l/min, whose efficiency exceeds 90%. But for now they are extremely expensive (the price of the specified copy is 1550 USD), and therefore are practically inaccessible to the average user.

Construction of a condensation column with a cylindrical burner

Typical breakdowns and how to fix them

Repairing a gas water heater is an activity for highly qualified specialists. However, some breakdowns can be fixed with your own hands. Before starting work, you need to close the water and gas supply taps. After this, you need to unscrew the mounting screws and remove the handles and speaker housing.

Here are some examples of when a gas water heater won't light up:

Water heaters with automatic ignition systems may run out of batteries. All you need to do is replace the batteries. For water heaters that have a built-in generator, the piezoelectric element, electrode or power cable may malfunction. It is necessary to clean the contacts of the automatic ignition system, check the electrodes and wires for malfunctions. If all these steps do not help, you need to check and replace the power button and the piezoelectric element. If there is no draft, you need to clean the ventilation; to do this, you should call a specialist. If the pressure is insufficient, you should pay attention to the water supply or heater assembly. All that is needed is cleaning the pipes, washing or replacing filters. If the gas water heater does not turn on, you should check and, if necessary, replace the membrane of the water unit. To do this, remove the water-gas unit and, by unscrewing the screws, separate its water part

Before removing the rubber plate, it is important to remember its location. Then you need to clean the inside of the lid and install a new rubber part on the plate with the stem

It is better to replace the membrane with silicone, which lasts longer. Finally, you can tighten the screws (preferably diagonally). Some gas devices have a knob for adjusting the water flow. If the column does not light up, you need to check how the mechanical switch is located. If the pressure is not large enough and the column does not start, you should set the knob to the leftmost position and switch to the right until the device turns on. You need to adjust the jet at startup.