The combined boiler combines several functions: a standard electric and indirect heater. The heating source is a tubular (coil) element or a coolant of the system. Such a device is used in various rooms, ranging from residential buildings to enterprises.
Water circulation is provided by a special pump, which is installed in the heating system. The installation of a combined boiler can significantly save on payment for electricity in the heating season.
A wide range of products allows you to choose equipment for price and quality, as well as for the parameters of the room. Modern manufacturers take into account the geometry of the room, performance, as well as the useful volume of the device.
The principle of operation and features of water heaters
Any of the devices for heating water is in the form of a sealed container with a thermocouple. There are several types of heaters, depending on the contact of the heater with water: contact and non-contact. The latter is somewhat different in design and high cost.
In a combined indirect heating boiler, a thermocouple is not provided at all. The process of increasing the temperature of water is carried out through heat transfer between the external fluid and the internal. "Working" water, which circulates along the internal closed loop of the boiler, gives its energy to the water in the tank, while ensuring its heating.
Circulation in a closed system is carried out by a pump. Units of this type are autonomous and do not need to be connected to the central highway.
Indirect heating boiler control system
Regardless of the type of heating (from a heating system with forced circulation of water or from a thermocouple), the control system consists of:
- Thermostat - for temperature control and regulation.
- System automatic on / off program.
- Multiple check valves.
- Power pump.
- Protection systems for overheating and voltage surges.
Advantages and disadvantages of combined boilers
The advantages include:
- Temperature equalization when using multiple water access points simultaneously.
- Ability to use without connecting to the central highway.
- Profitability.
- Easy to use.
- Quick installation.
- The presence of protective and safety systems.
- The ability to heat water in several ways (for example, during the absence of electricity).
Combined boiler also has disadvantages:
- The need to install sources of thermal energy. In the heating season, this is the boiler, and to use the boiler in the warm season, you will have to use heat pumps, solar collectors, etc.
- If the boiler capacity is large, considerable time is required to heat the water.
- Large dimensions (in comparison with geysers or flow heaters).
- High cost.
What to consider before buying
It is advisable to buy a combined boiler if the flow rate of warm water is more than 1.5 l / min. (for example, if more than 4 people live in the same house). It is impractical to attach a heater to an electric boiler.
When selecting, you should pay attention to the design of the boiler (especially the fastening of the coil to the inner wall). Due to constant contact with water, salts and sediments are deposited on the inside of the appliance. Some manufacturers weld the coil mount to the body. This feature does not allow the cleaning of elements.
Next, pay attention to the number of coils. If there are two or more, it becomes possible to connect the heater to two sources at once or alternately (for example, a boiler and a solar collector).
Very important are the materials for the manufacture of the coil and capacity. More reliable and durable material for the first is brass, and for the second - stainless steel.
Manufacturers rating
Powerful tips when choosing any technique are customer reviews. Based on the latter, a rating of manufacturers is compiled.
- Ariston The Italian company, which is known throughout the world, has been manufacturing various home appliances for over 20 years. A manufacturer with such experience has earned trust among customers with the reliability and quality of equipment. Due to its good reputation, Ariston is in first place in the ranking. Water heaters are produced in different volumes and geometric shapes. Composite materials used in technology are environmentally friendly and reliable.
- Combined Gorenje boilers are second in the ranking. The company is engaged in the development and production of a wide variety of technical products. The options for installations and geometric shapes of water heaters are endless. Each client can choose the equipment based on the parameters of the room. This feature is very important for narrow openings. The assortment of the company allows you to choose both a budget option with a conventional thermocouple, and more expensive with a dry one. Some devices are equipped with two ten.
- The French company Atlantic is in the middle of the ranking. The manufacturer provides the opportunity to choose a boiler for the required parameters. The main developments of the company are aimed at improving the technology of tanks. Among the latest technical solutions, water heaters with an enameled tank with impurities of titanium and cobalt and the same with zirconium content stand out. The use of new technologies in production increases their durability and at the same time rating among users.
- Perfezza. The young company is engaged in the invention and production of various equipment for heating water. The products of this manufacturer have won attention and popularity among users by the simplicity of design and low cost.
- Bosch water heaters are also common in this area. The manufacturer provides powerful equipment of various volumes. The model range is presented in a classic form (for installation in a vertical position) and in a rectangular one - in the form of combined floor boilers.
Design features of models
Regardless of the manufacturer, the boiler is connected to any type of boiler. A small technique is placed on the wall in an accessible position (vertical or horizontal). For mounting, special brackets are used, which are completed with the equipment. An important condition for installation is the availability of the necessary space in the room.
The design of the combined boiler provides threaded holes. This feature allows the consumer to connect heating elements that operate from the mains. An additional function is very convenient in the non-heating period, because to get warm water it is not necessary to start the boiler.
Water heater with multiple heat exchangers
The combined indirect heating boiler with PETN has several advantages. Most water heaters are equipped with just one thermocouple. Since the useful temperature directly depends on the PETN area, the presence of two or more sources allows you to adjust the power and performance of the equipment.
Each of the heat exchangers can be connected to:
- Heat pump.
- Solar collector.
- Heating system.
Such a design solution is effective when heating large volumes of water. Using several sources for heating allows you to optimize the costs of various types of energy and increase the potential of the equipment.
New manufacturers
The budget option among heating equipment is the combined Drazice boilers. In the new series of such devices, special heat-insulating foam is used, which ensures a long service life and insignificant heat losses. For equipment with a volume of over 300 liters, additional insulation materials are provided.
The use of modern composites can improve the energy class, while maintaining the original parameters. Also, all materials meet European standards. Innovative technologies of the company allow the production of energy class C boilers and higher.
Manufacturer's Reviews
Most often, reviews about various brands and specific brands are found on the Internet. User opinions on the Combined Boiler Gorenie were divided into positive and negative.
The positive characteristics included:
- Resistance to voltage drops.
- Ease of installation.
- Ability to clean at home.
- Simple water supply system.
- Fast heating.
- Low power consumption.
- The ability to adjust the temperature.
The negative points are:
- Inability to supply hot water during the absence of cold (due to work under pressure).
- Scaling occurs even on a dry element.
- Design leak in some models.
Production of indirect heating boilers at home
For the manufacture of necessary:
- Purchase or complete a tank yourself.
- Create a coil.
- Insulate.
- Assemble the structure.
- Connect the coil to the heating system.
- Serve cold water.
- Create a wiring for heated water (you can also mount a tap in the structure).
To install a home-made boiler of combined heating, you can use brackets. After installation, the device should be checked for leaks and for proper operation.
Important! When installing boilers of any type, safety precautions should be followed when working with heating elements, tools and electrical networks. Keep in mind the possibility of overpressure in closed circuits and tanks.