5 best double-circuit gas boilers

Double-circuit gas boilers have long been in demand in the heating equipment market. This is reasonable, because the equipment is designed to simultaneously heat rooms and heat water for hot water supply. In the assortment of popular manufacturers there are models for every taste. Before buying, you need to study all the pros, cons and features in order to ensure maximum comfort in the future.

We have compiled a list of the main parameters that are usually of interest to future buyers. In our article you will find the best models from the brands Bosch, Vaillant, Ariston, user reviews and technical specifications.

Structure

The main elements due to which the gas boiler works: control unit, heat exchanger and burner. The heat exchanger is installed above the combustion chamber, inside it the process of heating the coolant takes place. The operation of the device is fully automated – this ensures complete safety and allows you to control temperature conditions.

Types of heat exchangers

Doubled

The dual heat exchanger has two modules, which are considered as a single part. The primary module is responsible for heating the coolant for heating, the lamellar one heats the water. The primary element looks like a curved finned tube, the lamellar element is a set of compactly arranged plates.

Bithermal

Bithermal heat exchanger has two tubes – inner and outer. The internal one is responsible for heating water for hot water supply, and the external one is for heating.

Experts say that a dual heat exchanger is much more reliable than a bithermic one. In the heating system, the coolant circulates continuously in a circle, so scale is practically not formed. Running water is used for water supply, therefore a large amount of scale occurs, due to which this part of the heat exchanger often breaks down and needs to be replaced.

In a double heat exchanger, only the part that is responsible for hot water supply can be replaced. In the case of bithermic, you will have to change the entire module, and this is much more expensive. We also note that the design of the bitermal type is much more complicated, the part is practically not repairable and most often requires replacement.

Material

1. Stainless steel. The material is durable, but impractical. Due to insufficient heat transfer, efficiency decreases. Despite this factor, the part is quite expensive.
2. Cink Steel. Heat exchangers made of galvanized steel break more often than others. It is much cheaper than the rest, but will not last long.
3. Copper. All high-quality gas boilers are equipped with a copper heat exchanger. Good heat dissipation improves efficiency and reduces gas consumption. For all the benefits, you will have to pay a decent amount, but such a detail will justify the high cost.

If you choose a technique according to this criterion, it is easy to decide. Copper would be the best option. Of course, everywhere has its drawbacks. Copper has a low melting point, but automation clearly monitors the general condition of the device and prevents overheating.

Types of burners

All double-circuit models are equipped with atmospheric burners, they can be:

1. Single stage. To maintain the set temperature, the burner can go out and ignite, it does not have an intermediate position. It is difficult to call such a principle of operation reliable.
2. Two-stage. The burner can operate at 100% and 50-60% capacity. Automation independently maintains the specified mode and controls the power.
3. modulated. These are the most economical and reliable burners that are able to independently maintain the required power. Another plus is that fuel consumption is reduced by 10-15%.

Automation and mode control

Automation is an important and mandatory element, without which it is impossible to control and manage equipment. For safety, the device constantly monitors three main parameters:

• flame control;
• pressure;
• the presence of stable draft in the chimney.

These features need to be controlled first. In addition to the main ones, there are additional functions for which automation is responsible:

• Summer mode. In the summer, there is no need to use heating, so the device only works for domestic hot water. To prevent blockages in the heating system, the device periodically starts the circulation of the coolant.
• Postcirculation. After the burner is switched off, the heat exchanger maintains a high temperature. The water will boil and the device will stop working if the circulation pump is turned off immediately. To prevent malfunctions, the pump drives the coolant for some time and turns off after setting the permissible temperature.
• Antifreeze. If the boiler is used for a private house or dacha in which you are periodically, the economy mode starts.

Combustion chamber type

Open

Models with an open combustion chamber work according to a simple scheme – they take oxygen for work from the room. The device independently takes the amount of air that is necessary for stable operation.

This type of chamber requires the installation of a chimney through which combustion products and processed gases will be removed. For such a boiler, there must be good ventilation in the room, otherwise you may suffer from suffocation or lack of air.

Closed

By installing a boiler with a closed combustion chamber, there is no need to free the whole room. This option is suitable if you are limited in space – the installation will require only a few square meters. The air for operation is supplied with the help of a special fan that runs on electricity – this factor can be attributed to the minuses.

If you decide to purchase just such equipment, you need to install a coaxial chimney. The device has a fairly simple design – one pipe is installed in another. Thus, the air does not come from the room, but from the street, thanks to the installed outer pipe. All waste products are discharged through the outer pipe.

Installation

According to the type of installation, the models are divided into two – wall and floor. What equipment is better to buy in a small apartment? If you are a fan of simplicity and compactness, stop at the wall-mounted version. Wall models do not require a special room, they can be installed in any room. Despite the size, the device can heat a room with an area of ​​​​250 to 350 square meters. m.

Floor gas boilers should be installed in non-residential premises. The main rule that must be observed is good ventilation. Each manufacturer includes a list of requirements for a safe installation in the instructions. Connection and configuration of equipment must be carried out by a specialist.

Rating of the best brands

Most of all heating equipment on the market belongs to foreign manufacturers. Referring to the opinion of experts and users, we have compiled our list of the best double-circuit boilers, it includes models of manufacturers:

• Buderus;
• Bosch;
• Hotpoint-Ariston;
• Get out;
• Valiant.

Among Russian brands, one can single out the brand “CONORD».

Description and characteristics

Buderus Max U072-24 K

Buderus Logamax combines all the important parameters – true German quality, conciseness and style. The device is easily mounted on the wall, and takes up no more space than a conventional kitchen cabinet. Logamax U072 is not sensitive to gas pressure drops and power surges.

The system maintains stable operation even at a temperature of -35 degrees. The device has a flow sensor, a Hall sensor and a coarse filter – all elements can be easily disassembled and cleaned. Additional security is provided by automation, which fully controls all processes.

Bosch Gaz 6000 WBN-18C RN

The model has a power of 18 kW and an efficiency of 93,2% – this allows you to heat rooms up to 144 m². A big plus for Bosch is the low gas consumption, which does not exceed 2,1 m³ per hour at maximum power. Automation controls the voltage in the network and maintains stable operation with voltage drops from 165 V to 255 V.

Note the compact dimensions that allow you to install the device even in small rooms.

Hotpoint-Ariston Atleas X24 FF

Ariston rightfully occupies one of the first places in the heating equipment market. The entire line is famous for its advanced security system.

The Atleas X24 FF has a net power of 24 kW and an efficiency of 93,2%. For complete protection, the automation is triggered in the event of: a drop in gas pressure, lack of traction, overheating of the water, extinguishing of the flame and freezing of the liquid in the circuit. A stylish display and the Ariston logo complete the picture.

BAXI Eco Four 24 F

Baxi Eco Four 24 F is a fairly advanced model. In addition to heating and water heating, the boiler can be used for the “warm floor” system. The automation includes 7 protection systems, including the anti-freeze mode. This mode can also be used during departure. Summer mode provides for turning off the heating system during the summer season and using appliances only for hot water supply.

Vaillant atmo TEC pro VUW INT 200/5-3H

Vaillent atmo TEC pro is suitable for space heating up to 160 m². It is worth noting the presence of a summer mode, thanks to which the device can only be used to heat water. Vaillant has several levels of protection: against water overheating, circulation disturbance, flame extinction, and so on.

Reviews

Andrey, Stavropol

After the repair, I had to think about creating an independent heating system. We chose between Proterm and Navien. We wanted equipment with convenient controls, but were embarrassed by high prices. After lengthy disputes, Proterm was bought. With his help, we got not only our own heating, but also hot water. Most of all I like the high-quality protection system. When the gas was cut off, the system drove water in emergency mode so that it would not freeze. It is a pity that a non-volatile boiler did not fit our requirements. And with this: no electricity – no heating.

Inna, Kirov city

For a long time I did not know how to choose a technique and not make a mistake. After listening to my friends, I bought a model from Lemax – the price was right and everything seemed to fit according to the characteristics. When the purchase was brought, the first question was, what is it and how to use it? Over time, I figured out the settings and controls – nothing complicated if you read the instructions. Although I still don’t know how some modes work. I would not say that my choice was correct. In the spring, the burner itself began to go out, and it was practically impossible to re-ignite it.

The right choice of a double-circuit boiler is a guarantee of a comfortable life with uninterrupted heating and hot water. We hope that our article will help you decide what you want to see in a future purchase. Do not forget about the rules of safe operation, and the equipment will serve you for decades.