Mounting Features
When deciding how to install and connect a water heating boiler to the water supply, consider the following recommendations:
- According to the rules for installing water heaters, hot water pipes must be supplied to plumbing fixtures in thermal insulation with a shell thickness of at least 20 mm, its thermal conductivity coefficient should not exceed 0.035 W / m2. Fulfillment of this condition reduces heat losses in the line, saves electricity and, accordingly, the financial resources of the consumer.
- It is also desirable to have insulation on metal pipes made of steel, stainless steel or copper in the cold water supply line (CWS). The main purpose of thermal insulation on the cold water supply pipeline is to prevent the formation of condensate, which causes the appearance of mold and mildew, corrosion.
Rice. 14 Indirect heating boiler in an individual house
- A common malfunction of many boilers is water leakage through the side fitting of the safety drain valve, caused by high pressure in the water main (found on the first floors of high-rise apartment buildings). Usually, water is diverted to the sewer using a flexible piping attached to the side fitting, which is not always convenient. One option to avoid installing an interfering hose is to install an expansion tank on the broiler to compensate for pressure drops.
- As a rule, an expansion tank is placed on indirectly heated boilers or large-capacity tanks with a large amount of water, where small temperature fluctuations cause significant pressure drops.
- When installing boilers, it is necessary to select a power cable with heat-resistant insulation; a ground loop is required in the electrical circuit. The power supply system of the water heater must have an RCD protective shutdown device.
- When operating powerful boilers with an energy consumption of more than 5 kW, they are fed with a three-core copper wire of large cross section (2 - 2.5 mm2) from the shield, conducting a separate electrical line, the most commonly used brands of electrical cable are VVG 3x2.5-380, PPV 3x2.5- 380.
- To increase the service life of heating elements of water heaters, a magnetic filter is installed in the water supply system, which prevents the deposition of metal salts on the surface of the heating element.
Rice. 15 Connecting a typical boiler to the electrical network
Types of electric water heaters
There are two large groups: flow and storage. Instantaneous water heaters heat the water that passes through them. In this regard, they are relatively small in size, but very high power - up to 24 kW, but this is the maximum. For washing dishes and taking a shower, a power of 4-6 kW is enough, for taking a bath - 10-12 kW. So, to connect such equipment, a dedicated power line with an RCD is required.
Water heaters of various types
Storage water heaters are also called "boilers", they have a reservoir and a small, compared with flowing, power - from 0.8 kW to 4 kW. However, a separate power line is also desirable for them. Boiler sizes depend on the volume of water contained in the tank. Their shape is cylindrical, and the cylinder can be located vertically (cheaper option) and horizontally (more expensive).
The place for installing the water heater is chosen mainly depending on the existing connection conditions. Most often, this is either a bathroom or a kitchen: water is supplied to both rooms. Secondly, the place is chosen for aesthetic reasons: so that the equipment is not very “striking” to the eye. From this point of view, a toilet or a bathroom is usually chosen. If space is available, this is the best choice.
Types of water heaters
In individual houses, in the absence of a central water supply line, water is obtained from well or borehole sources, pumping it into domestic water supply using submersible or surface electric pumps (pumping stations). At the same time, for a comfortable stay, the consumer needs hot water, which can be obtained in various ways. A popular option for a water heating unit is a gas water heater, which is installed if the house is connected to a centralized gas supply line.
In the absence of gas in an individual house or apartment, the only convenient option for heating water remains (it makes no sense to consider a heating boiler because of the technological difficulties in obtaining consumable hot water in it) - the use of various types of electric water heaters (boilers).
Another method of heating cold water for homes deprived of electricity and gas is wood-burning (solid fuel) columns with the common popular name Titan.
Rice. 2 How to connect Titanium - piping and structural arrangement of a solid fuel column
Flowing. They are a tubular electric heating element (TEH) in the form of an uninsulated spiral, placed in a pipeline, inside which water flows, it turns on only when water is consumed.
To ensure through heating of a large volume of water to a high temperature, a significant electric power of the device of about 10 kW will be required (it will still not be enough to heat the volumes of water required to simultaneously fill the bath, take a shower and wash dishes). Not every wiring in a private house can withstand this power (for its comfortable supply of hot water, 20 kW of heater power will be needed), and even more so in an apartment.
To supply electricity to the water heater, you will have to run a separate line with a large cross-section wire from the electrical panel, which is not always acceptable and leads to significant financial costs. Therefore, a flow heater is a device for small volumes of hot water consumption.
Rice. 3 The main components of the instantaneous boiler water heater
Cumulative.
General tips for installing a water heater with your own hands
In addition to choosing the type and model of a device for heating water, before proceeding, it is necessary to determine the following important points:
- Throughout the entire period of operation, access to the device must be free.
- The wall on which the heater is supposed to be hung must have a double margin of safety, that is, when installing a boiler of 150 liters, it must withstand a load of 300 kg.
- Analyze the condition of pipes and risers, the availability of outlets for connecting the device. In some cases, it will be necessary to replace both risers and pipes in the apartment.
- If the wiring in the apartment has not changed for a long time, then invite a specialist to determine its condition and cross section, and also whether it can withstand the load from the device you have chosen. After the examination, you will know for sure whether you need to change the wiring or not.
The presented table makes it possible to choose an electrical cable (copper) with a minimum cross section that can be used to connect the equipment you have chosen:
| Power, kWt) | Current (A) | Minimum cross-section of conductor (mm2) |
| 1,0 | 4.5 | 1 |
| 2,0 | 9,0 | 1,5 |
| 2,5 | 11,4 | 2,5 |
| 3,0 | 13,6 | 2,5 |
| 3,5 | 15,9 | 2,5 |
| 4,0 | 18,2 | 4 |
| 4,5 | 20,5 | 4 |
| 5,0 | 22,5 | 4 |
| 6,0 | 27,3 | 4 |
| 8,0 | 36,4 | 6 |
| 9,0 | 40,5 | 10 |
It is important to remember that if aluminum wire is used instead of copper wire, a multiplying factor of 1.3-1.5 must be used. Common mistakes or what not to do
Common mistakes or what not to do
If you have decided to independently install a flow or storage electric heater, in no case should you:
- Replace any of the components included with the device.
- Connect the device to the network in the absence of water in it.
- Remove the protective casing or cover when connecting the water heater to the mains.
- Use the unit without grounding.
- Turn on the equipment when the pressure in the water supply system is too weak or too strong.
- Drain water from it in a state connected to electricity.
Standard wiring diagram
A person who has a general idea of the layout of the water supply network on an apartment scale and the concept of operation of a storage electric water heater will not be difficult to figure out with the order of its connection to the pipes of cold and hot water supply.
Boiler connection diagram in the apartment
So, cold water must be supplied to the boiler
This is done by inserting (mounting) a tee in the most convenient place under specific conditions.
A safety group must be installed on the supply pipeline - one or more special valves. Their importance and installation rules will be discussed below in a separate section of the article.
The outlet pipeline of heated water cuts into the network of the local apartment hot water supply - directly to the passing pipe - through the installed tee, or, preferably, to the collector. If the apartment is connected to a centralized hot water network, a tap must be installed that will cut off, as necessary, the internal network from the common riser.
- This generally accepted scheme can be supplemented with some elements. So, many masters prefer to install tees with taps in front of the entrances to the boiler on both hot and cold pipes, which make it easy to empty the electric heater tank for maintenance or repair work. This somewhat “weights” the installation process, but gives certain conveniences in the future.
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If pressure surges often occur in the cold water supply network, or the water pressure goes beyond the values \u200b\u200ballowable for a particular boiler, a water reducer will be required. It will equalize the pressure and protect the electric heater from hydraulic shocks.
Another addition would be a thermostatic mixing valve. It will provide an even, pre-set temperature in the hot water supply system, eliminate the possibility of possible burns, etc. However, to install it, you will need to insert another tee in the cold water pipeline - in the thermostatic valve itself, hot and cold flows are mixed to the required temperature.
Scheme using a thermostatic valve
