- The role of a technical well in the water supply system
- Excavation and construction of the caisson
- Introductory part of the highway
- Water supply manifold device
- Equipment in the caisson of the pumping station
When entering a water supply system in a country house, it is necessary to equip a place for the installation of shut-off and control valves and metering devices. As a rule, the best option for this is the device of an underground technical well, where communications and equipment will not freeze..
The role of a technical well in the water supply system
Connection to the main water supply system is performed in compliance with a number of technical requirements. It’s not only about the tie-in point itself, but also about a number of technical devices that must be installed between the supply main and the consumer system. These include:
- Ball valve or gate valve.
- Mud filter.
- Water measuring device.
Each of these elements of plumbing equipment has certain requirements for operating conditions. The regulation limits the temperature range and maximum humidity, plus there is a need to protect the equipment from mechanical damage. Of course, all the equipment mentioned can be placed in the house, but this solution has a number of disadvantages. Not everyone wants to let an inspector into their home who checks the status of the metering unit and the compliance of the readings.
On the other hand, a number of draw-off points can be located along the path of the inlet pipeline and it is impractical to pull the additional water supply branch in the opposite direction. It can also be planned to use a centralized water supply system together with its own source – a well or a well, which means that placing an input node in a house causes even more serious difficulties..
After all, the removal of all the technical elements of life support from the living space is a concept that has proven its convenience in practice. The underground placement of plumbing equipment meets all the requirements, so freezing of the system and any harmful effect is excluded, it is only important to correctly build and equip a well.
Excavation and construction of the caisson
It is most reasonable to dig a hole at the stage of laying an introductory water pipe. The RMNT.RU portal has already written how to enter water into the house. This will greatly simplify the tie-in of the shut-off and control valves and their passage through the walls of the well. As a rule, the pit is in the shape of a square with a side of 1.2 m, however, in the case of organizing complex branched systems, more internal space may be required. An increase in the pit may be dictated by the need to accommodate more plumbing equipment, or due to the need to apply external waterproofing.
Protection from groundwater is required only at a sufficiently high level, when there is a risk of soil erosion and collapse. In other cases, it is often more advantageous to use special fittings that are resistant to flooding. The walls of the so-called wet well are laid out in one brick according to the beam pattern, while the bottom remains unpaved and a depression is necessarily dug in it, which allows you to quickly pump out all the water in case of emergency. The dry caisson is a sealed concrete bowl. Instead of carrying out monolithic works that require significantly more forces and materials, you can resort to proven prefabricated monolithic structures from a round plate at the bottom and rings connected by bentonite locks.
Introductory part of the highway
In the simplest water wells, there is only one unit of shut-off and control valves: a valve with a nominal pipe diameter of up to 50 mm, and on larger pipelines – a valve. However, when installing the metering unit in the well, the installation of additional plumbing equipment is required..
First, the counter itself. In a wet well, it is allowed to install only water meters capable of operating in water under pressure for a long time. They are characterized by a cast metal body and a small, thick viewing window, sometimes equipped with a magnifying lens. Recently, electronic-type underwater meters that do not have a dial as such have become more and more popular. Often, water meters with enhanced protection are also installed in dry caissons: simply out of safety net or lack of understanding of the requirements of the standards.
Between the tap and the meter, it is necessary to install a dirt strainer with a mesh size of 200 microns to 0.1 mm. It is better to clarify the exact technical parameters of the filter in the meter’s passport, but one requirement is the same for all water-measuring devices – the filter should not be able to be flushed, otherwise the water supplying organization will inevitably have problems with sealing. The third mandatory element of the meter piping – a check valve – can be of any type and be installed both directly in front of the water meter, and immediately after it.
Water meter piping in the caisson: 1 – shut-off valve; 2 – coarse mesh filter; 3 – check valve; 4 – water meter; 5 – tap for draining water from the system
It may also be required to install a crane after the meter. This will greatly facilitate the dismantling of the meter without draining the water from the system for sending it for verification and putting into operation an alternative source of water supply without any modifications. Also, immediately after the meter and its piping, it is highly recommended to install a tee with a conventional 1/2 “tap for emergency drainage of water from the system..
Water supply manifold device
The distribution unit of the water well is conveniently organized on a polypropylene pipe system. Possible risks of narrowing the nominal bore due to poor-quality soldering can be easily leveled by simply increasing the diameter of the pipes by 1-2 standard sizes. At the same time, polypropylene is very tolerant of flooding and freezing, and if necessary, the well piping can be easily changed..
The most common types of water supply manifolds also contribute to this. They are molded from PPR plastic and have 3 to 6 outlets with ball valves. Their quality is a key indicator of the durability of the collector, so frankly cheap Chinese-made products should be avoided..
With outgoing pipe diameters over 32 mm, it can be quite difficult to select a suitable collector; an atypical device will be required. As a rule, it is a pipe segment with a diameter of up to 100 mm, plugged on both sides, into which threaded bends are welded to connect outgoing lines through a squeegee or a union nut..
It is also possible not to install the manifold assembly as such, but simply mount a series of branch fittings in series under the main diameter of the inlet line. Thus, the pipe after the water meter encircles the walls of the well, branches of the system cut into it in the right places. This method of the device requires much more costs for expensive fittings and is suitable only as a temporary measure due to the large number of connections, each of which is a vulnerability.
Equipment in the caisson of the pumping station
When the collection unit is located close to a well or a well, it makes sense to move the complex of equipment of the water pumping station underground. This eliminates the need to lay additional pipes, and all electrical and plumbing equipment will be operated in suitable conditions. Of course, the pumping and filtering stations can only be installed inside a dry caisson..
Although it is not possible to flood equipment in a watertight well, condensation is very likely to form on the metal elements. Therefore, the use of steel fittings should be avoided in favor of bronze or, in the worst case, brass. It is also advisable to choose a battery with a stainless steel casing instead of the standard painted steel one. The pump and filter housings must also have a design that meets the placement conditions in accordance with GOST 15150-69.
When placing a water treatment station in a caisson, it will not be superfluous to think over the design of a double cover. A partition with a ladder or a collapsible boardwalk should be located at the level of freezing of the ground or lower and have a deaf vapor barrier. If it is impossible to place the partition at such a height, you should consider its external insulation, for which it is convenient to use the cheapest PSB brand expanded polystyrene. Only when the correct insulation is performed can we confidently eliminate the risk of well freezing and damage to expensive equipment.