Everyone needs to create the most comfortable living conditions. However, without basic amenities, such as round-the-clock access to hot water, this can not even be discussed. To provide the latter is capable of a flow-type water heater. Let's see what are the main points that deserve attention when choosing equipment of this plan.
Design
Structurally
gas flow
water heaters consist of the following elements:
- Detectors for traction and system overheating.
- Fuel flow regulator.
- Gas-burner.
- Inlet and outlet nozzles for water supply.
- Exit to the chimney.
- Chamber for combustion products.
- Heat exchanger.
Compared to other common systems, any instantaneous water heater has a rather modest size due to the lack of a hot water tank and the use of a small size gas burner. The successful installation of such units can be carried out without problems in small rooms that have natural ventilation.
Performance
This parameter is usually indicated in the technical documentation of equipment in measuring units l / min or in kW. Determining the necessary indicator allows the calculation of the number of points of water intake. In other words, the outlets of the mixers.
It is believed that one tap for water supply passes about 6-7 liters of fluid per minute. When choosing a Polaris instantaneous water heater or another popular model in an apartment, where one mixer is installed in the kitchen and in the bathroom, it is enough to use a simple calculation. To freely use hot water in both rooms, you will need to install the unit with a capacity of not more than 13 l / min.
Based on this example, you can quickly find an efficient flow-type water heater based on the power parameters noted in the table on the case.
Water pressure
If we talk about choosing a gas heater according to this criterion, attention should be paid to several points: the maximum water pressure that the heat exchanger is designed for, and the minimum pressure that is required to turn on the device.
The first indicator is important only for the reason that in centralized water supply systems, sudden changes often occur. The latter can cause water hammer, which affect the design of the water heater. The choice of a unit with an insufficiently strong heat exchanger is fraught with its rupture and damage to elements that act as conductors of the coolant. A sufficient level of maximum pressure is considered an indicator of about 11-12 bar.
When choosing a flow-type water heater, it is important to correlate the indicators of stable pressure in a centralized water supply system with its minimum level necessary to activate the unit. Attaching importance to this moment is especially important for owners of apartments in old buildings, where it is often necessary to put up with worn out communications. In this case, it will be best if the flow-type domestic gas water heater has the property of starting up at a pressure value of not higher than 0.15 bar.
Type of ignition
Separate models of gas flow water heaters are distinguished by different options for ignition of the burner:
- Budget units - usually have a manual ignition, which is carried out by bringing a burning match to the omentum. This method is very convenient, given the fact that the operation of the device with a round-the-clock wick can not be called economical.
- Piezo ignition - is provided by activation of an electromechanical oil seal integrated into the system. Such a solution does not provide any obvious advantages compared to the previous version. However, in this case, the burner ignites faster. And for this, just a click of a button is enough.
- The most advanced models have an electric ignition function. Non-volatile and volatile components are used here. In the latter case, when the room is de-energized, the instantaneous water heater "Termex" or any other unit that functions according to the indicated principle will simply stop working.
Power modulation
Such a complete set of gas water heaters is used to automatically control the intensity of combustion of the flame, based on the pressure of the water entering the unit. A very convenient function that makes it possible to enjoy the operation of the device, regardless of the pressure drop in the centralized water supply system with an increase in the number of users.
By installing a flow-type water heater "Electrolux", which has this structural element, you can significantly reduce gas consumption and significantly increase the level of comfort during operation of the unit, without looking at the number of active points of water intake in the room.
Heat exchanger type
It is customary to classify heat exchangers of domestic water heaters according to the material of manufacture:
- Steel structures - are distinguished by corrosion resistance. However, they have a fairly high price. Steel parts are heavy, but also more reliable.
- Heat exchangers made of high-purity copper - have the qualities characteristic of steel counterparts. At the same time, the level of heat transfer is much higher. Therefore, copper structures have an increased efficiency.
- Ordinary copper - the presence of impurities in the metal structure leads to uneven heating of the surfaces, which causes the appearance of small cracks. To avoid a quick failure, manufacturers of units of the budget category cover the elements of the heat exchanger with heat-resistant compounds. However, such a solution does not bring tangible benefits. After all, the parts still burn out for several years of continuous operation.
The method of removal of combustion products
Depending on the implementation of certain solutions for the removal of carbon monoxide, several variants of flow-type water heaters are distinguished.
The first is traditional, with a chimney. Looks unacceptable for sale in city apartments. Since in most cases there is no way to remove the chimney to the roof.
The second is parapet, where the removal of carbon monoxide from the system occurs through a pipe, the end of which is extracted out through a specially prepared hole in the wall. In addition to the increased cost, this type of equipment is dependent on electricity, since the exhaust gas is removed due to the operation of a fan built into the body of the water heating unit.
Security features
If an EVPZ-15 instantaneous water heater is installed or another high-performance model, the presence of the following components is considered a prerequisite for the safe operation of the system:
- Ionization detector - automatically turns off the unit when the flame suddenly extinguishes.
- Pressure relief valve - vents excess gas in case of exceeding the permissible pressure in the pipes.
- Draft level controller - blocks the water heater in case of insufficient draft in the smoke channel.
- Low water pressure detector - prevents the system from activating at low pressure in the water supply system.
- Overheating sensor - turns off the water heater when the water is heated to the limit value.
Installation of a flow-type water heater
Installation of such systems needs preparation. To begin with, it is worth developing and coordinating an appropriate project. Then provide a gas pipe to the installation site. In conclusion, it is necessary to take care of the installation of a gas meter.
Installed "Polaris" instantaneous water heater , like other popular models, in several successive stages:
- Marked places for drilling holes for fasteners.
- The design is hung on hooks mounted on plastic dowels.
- The water heater is connected to the chimney using a special corrugated pipe.
- The unit is connected to the gas supply network with a certified hose. All connections are checked for leaks.
- Hot and cold water is supplied. Pipes are connected to the contacts with the corresponding red and blue designations.
- The taps open and the connection is checked.
- The unit is adjusted according to the recommendations from the attached instructions.
Advantages and disadvantages
What makes a consumer prefer gas-fired flow water heaters? In the first place go the small dimensions of devices in this category. Other arguments in favor of such systems are round-the-clock access to hot water, affordable cost, ease of transportation, assembly, installation and maintenance.
The only drawback of such water heaters is the need for the availability of appropriate conditions for smoke removal.
Eventually
Instantaneous water heaters look extremely attractive to the domestic consumer, since they allow eliminating numerous discomfort factors that are characteristic of the operation of other common systems.
When going shopping, it is extremely important to know the possibilities of communications available in the house. It is also worth asking about the power that the selected water heater consumes, and then finding out the approximate amount of water that can provide the unit for individual needs or for all at the same time.
Of particular importance is the complexity of installing equipment in existing conditions. Sometimes they manage to cope with the installation on their own, thus reducing overall costs. However, in most cases, you have to resort to the help of specialists.
The main criteria that should be relied upon when choosing such units are: reliability and durability, affordable cost, functionality and ease of management, as well as an increased level of safety during operation.