Automated water supply is used to create autonomous cold and hot water supply systems, as well as sewer communications. This is especially true for suburban real estate objects, the connection of which to centralized engineering and technical communications is difficult, or even impossible.
The heart of the automatic water supply system is the pump. What is a submersible well pump? How to choose the best option and what could be the design scheme of automated water supply?
Submersible devices are usually divided into the following types:
- Units with built-in automation. Such pumps are the most effective solution for equipping an autonomous water supply system. Built-in automation allows not only to regulate the pressure and pressure of the liquid in the system, but also protects the device from power surges in the electrical network, and also prevents “idling” operation with insufficient depth. As one of the striking examples, one can cite a submersible pump for a well with Grundfos automation and the like.
- Devices with a so-called “check valve”. Such modifications are good in that their design almost completely eliminates the return of water from a closed system back to the tank.
- Vibrating. This type of units allows them to be used in various conditions and at large depth ranges. At the same time, most of these devices are able to work with liquids of a relatively coarse degree of purification.
- Drainage and fecal. This type of units is used for pumping water with a large amount of impurities, suspensions and rather large foreign fragments.
- Devices based on the principle of centrifugal action. They are quite versatile, as they can be used both in wells and in wells. But they are quite demanding on the preliminary filtration of the liquid and are relatively difficult to maintain and repair.
Types of automatic systems
Most submersible well pumps on the market today are based on on two principles of operation of automation:
- Application of hydropneumatic system;
- Use of electronic components.
More simple hydraulic accumulator system is a combination of a tank (hydraulic accumulator) and one or more relays, which allows you to adjust the pressure of the liquid in the pipeline or in the hose system.
Electronic automatic system allows to achieve significantly higher efficiency, since digital mini-blocks are installed directly in pipelines, or even in the device body (for example, Grundfos). However, the accuracy of adjustment and high service capabilities dictate a significantly higher cost of the entire system as a whole.
On the one hand, a well pump with pneumatic type automation is much cheaper. On the other hand, it has a much lower performance and accuracy in adjusting the water supply.
How are pumps selected?
The most popular types of submersible pumps used to equip autonomous water supply systems for country houses are vibrating and centrifugal.
The choice in favor of one or another principle of action is determined by the following aspects:
- Distance of the well/source of water from the building. If the tank is located no further than 10–20 meters from the house, then any unit will cope with the water supply. If the well is located at a more distant distance, then the characteristics of the water rise height declared by the manufacturer become decisive here. A distance of 20 to 50 meters requires a lifting power of 20 meters, and a further location is already 40 meters. In this case, it is necessary to add the height of the water rise to the tap in the house.
- Characteristics of the water in the well. For water that does not include many foreign particles, suspensions and suspensions, any type will do. For dirtier and lower quality water, vibration pumps must be used.
- Water intake method. For the arrangement of autonomous water supply and sewerage systems of a country house, units with an upper water intake look much more preferable. Firstly, engine cooling in such devices occurs naturally. And secondly, automation does not allow such devices to overheat at idle in the event of a drop in the liquid level in the tank. True, the performance of devices with an upper intake, as a rule, is inferior to samples with bottom water supply.
How does automation work?
The main purpose of automation is to uninterrupted supply of water (or pumping out liquid), as well as to prevent the failure of the engine of the unit as a result of overheating due to lack of cooling.
Overheating occurs mainly due to a drop in the water level in the tank, in other words, the shallowing of the well.
To avoid such problems, modern submersible well pumps can have the following types of automatic protection:
mechanical system automatic protection is based on a fairly simple principle. A submersible pump, freely drifting in the tank, is connected with a thin fishing line (or nylon thread) with a special float.
As soon as the water level falls below a certain value, limited by the length of the fishing line, a sensor is activated that turns off the power.
It’s like fishing with a fishing rod, only turned upside down.
The use of pressure indicators involves a more complex scheme. It uses a special sensor that controls the water pressure in the pipeline or in the hose system. As soon as the unit stops sucking water and starts supplying air to the system, the sensor sends a signal to the controller, which instantly turns off the device. In modern devices, such a sensor often has the ability to adjust settings. This principle is widely used, for example, in devices for a well with automatic brands “Aquarius” and other popular brands.
Electrical protection uses a completely different principle to prevent “dry running” of the engine. The fact is that when pumping water masses, the motor consumes a much larger amount of electrical energy than when pumping air. The built-in sensor is sensitive to changes in the “needs” of the engine for electricity and blocks the operation of the power unit.
The following video clearly demonstrates how the electronic protection system of an automatic submersible pump works:
Comparison with other types of water pumps
In addition to submersible pumps, other types of water pumping units are also used to create autonomous systems of cold and hot water supply or sewerage:
- pumping stations;
- Semi-submersible (floating) pumps.
Injection stations are a rather complex and rather expensive structure. In addition, they have rather large dimensions, consume incomparably more energy and are characterized by a rather high level of noise during operation.
The stations are mainly used in the construction of autonomous water supply systems for large cottages, villas or even collective households.. In addition, the pumping station is used at a significant depth of groundwater and in other special cases associated with certain hydrogeological characteristics of a particular land plot.
In most simple situations, the use of a station to supply water from a well is not considered appropriate, both in terms of efficiency and from an economic point of view.
As for the surface, then they, on the contrary, have a rather low power and productivity and are quite vulnerable to weather or atmospheric phenomena. Although they are relatively inexpensive and easy to maintain, they are nonetheless are not able to ensure the uninterrupted functioning of a full-fledged water supply or sewerage system for households. In addition, due to design features, floating systems can only be used in the warm season.
Video — How to choose and connect a hydraulic accumulator and automation?
In order not to force the unit to work every time the cranes are turned on, a hydraulic accumulator or drive is used.
It is a membrane tank (aluminum, steel or plastic), about half filled with water. With a decrease in the water level in the accumulator, the air pressure also drops, as a result of which the relay is activated, turning on the pump, which, in turn, refills the tank with water to the set value.
The choice of the capacity of the accumulator depends on the volume of water consumed and on the conditions of use of the premises.
- For a large cottagein which people live year-round, it is more expedient to choose drives with a volume 50 liters or more.
- BUT for a small summer cottage a compact hydraulic accumulator with a capacity of 5–10 liters.
Typical installation diagram of a water supply system from a well with a hydraulic accumulator as follows:
- The drive is installed indoors;
- On top of the tank in a vertical position is installed pressure switch;
- The hydraulic accumulator is connected by means of hoses or pipelines to the submersible pump on the one hand, and to the water supply taps on the other.
The following two videos detail the assembly of the pump group and the connection to the accumulator:
Prices for well pumps with automatic
Vibration-type devices are traditionally the most affordable. So, for example, a domestic-made unit can be purchased for 20–30$, if the height of the water rise is up to 40 meters. The same devices with a greater lifting depth are in the range of 4–70$.
Centrifugal devices are more expensive. Depending on the power, productivity and method of water intake, their cost can be from 8 0 to 150$. A typical example is the popular family of devices manufactured under the brand “Aquarius”. And especially productive units — the so-called water cannons — are even more expensive.
However, the price of a very popular on the market submersible pump for a well with automatic equipment “Dzhileks“featuring high performance and versatility, is near the mark in 200 dollars. Which, of course, is one of the most optimal combinations of “price / quality” parameters.