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Having your own water source is just great. And it’s even better if these are wells – usually the water in them is cleaner than in wells and they can supply water for longer. But for water to get into the house from it, a whole system is required, the basis of which is a well pump.
Selection options
Well pumps are easy to distinguish even by their appearance. They are an elongated cylinder made of stainless steel or plastic. Naturally, stainless steel models are more expensive – the steel must be of high quality (usually food grade AISI304). Pumps in a plastic case are much cheaper. Although they are made of a special impact-resistant plastic, they must be handled with care – it still does not tolerate shock loads very well. All other parameters will have to be selected.
Water flow and pump performance
In order for the water in the house or in the country to be with sufficient pressure, equipment is needed that can deliver the required volume of liquid. This parameter is called pump performance, measured in liters or milliliters (grams) per unit of time:
- ml/s – milliliters per second;
- l / min – liters per minute;
- l/h or cubic/h (m3/ h) – liters or cubic meters per hour (one cubic meter is equal to 1000 liters).
Borehole pumps can lift from 20 liters/min to 200 liters/min. The more productive the unit, the greater the power consumption and the higher the price. Therefore, we choose this parameter with a reasonable margin.
The required amount of water is calculated by two methods. The first takes into account the number of people living and the total expense. If four people live in the house, then the water consumption per day will be at the rate of 800 liters (200 l / person). If there is not only water supply from the well, but also irrigation, then some more moisture must be added. We divide the total amount by 12 (not by 24 hours, because at night we use water supply to a minimum). We get how much we will spend on average per hour. Dividing it by 60, we get the required pump performance.
For example, for a family of four and watering a small garden, it takes 1500 liters per day. Divide by 12, we get 125 liters / hour. In a minute it will be 2,08 l / min. If you often have guests, you may need a little more water, so we can increase the consumption by about 20%. Then you will need to look for a pump with a capacity of about 2,2-2,3 liters per minute.
Lifting height (pressure)
When choosing a pump for a well, you will inevitably study the technical specifications. There are parameters such as lifting height and immersion depth. Lifting height – also called pressure – is a calculated value. It takes into account the depth from which the pump will pump water, the height to which it must be raised in the house, the length of the horizontal section and the resistance of the pipes. Calculated according to the formula:
An example of calculating the required pressure. Let it be necessary to raise water from a depth (pump installation site) of 35 meters. The horizontal section is 25 meters, which equates to 2,5 meters of elevation. The house is two-story, the highest point is a shower on the second floor at a height of 4,5 m. Now we consider: 35 m + 2,5 m + 4,5 m = 42 m. We multiply this figure by the correction factor: 42 * 1,1 5 = 48,3 m. That is, the minimum pressure or lifting height is 50 meters.
If there is a hydraulic accumulator in the water supply system of the house, it is not the distance to the highest point that is taken into account, but its resistance. It depends on the pressure in the tank. One atmosphere is equal to 10 meters of pressure. That is, if the pressure in the GA is 2 atm, when calculating, instead of the height of the house, substitute 20 m.
Immersion depth
Another important parameter in the technical specifications is the immersion depth. This is the amount with which the pump can pump out water. It varies from 8-10 m for very low-power models to 200 m and more. That is, when choosing a pump for a well, you need to look at both characteristics at once.
How to determine how deep to lower the pump? This figure should be in the passport for the well. It depends on the total depth of the well, its size (diameter) and flow rate (the rate at which water arrives). In general, the recommendations are as follows: the pump should be at least 15-20 meters below the water surface, but even lower is better. When the pump is turned on, the liquid level drops by 3-8 meters. The amount remaining above it is pumped out. If the pump is very productive, it pumps quickly, it must be lowered lower, otherwise it will often turn off due to lack of water.
Well diameter
An important role in the selection of equipment is played by the diameter of the well. Most domestic well pumps have sizes from 70 mm to 102 mm. In general, this parameter is usually measured in inches. If so, then the easiest way to find three and four inch specimens. The rest are made to order.
Well pump type
Just a few words about the type of installation of the pump for the well. In general, there are submersible and surface devices. Surface ones are good because they are always in sight and available, there is only a hose in the water source. But there is one “but” – they have a maximum suction depth – about 8-10 meters. Wells of such depth, if they exist, are very rare. There are, of course, surface pumps with an ejector. They can get water from a depth of 20-30 meters, but such installations have low productivity, and the meter winds with a vengeance. So there is essentially no choice – only a submersible pump is required for the well.
The most widely used are two types of submersible well pumps: vibratory and centrifugal. Vibrating ones are attractive for their price – they cost several times less than the cheapest centrifugal ones. But they are not recommended for pumping drinking water. The reasons are:
- During operation, the vibration pump creates tangible vibrations in the water, which raises the sediment from the bottom. Therefore, the water supplied by such a pump will never be transparent.
- There is a strong opinion that the use of vibration pumps significantly reduces the life of the well – it silts up faster.
- The pump hits the well walls hard and makes a lot of noise. The beat can be weakened by putting safety rubber rings on the body (if the whole structure fits into the well), but nothing can be done about the noise.
- These pumps differ in low productivity and the depth from which they can lift water.
That is, vibration pumps for shallow wells, from which water is pumped for irrigation. Then their use is justified.
A centrifugal pump for a well is much more productive equipment. Water is pumped due to the rotation of the impellers, which create a vacuum in the center and increased pressure at the periphery. Due to the high pressure along the edges, the water rises, and a new portion is sucked into the zone of low pressure in the center. This is how water rises.
Centrifugal borehole pumps are not very noisy, water can be lifted from great depths. Their disadvantage is that they are sensitive to mechanical impurities that may be in the water – the working parts are worn out. Therefore, they are suitable only for pure water – the maximum content of impurities is from 100 g / m3, for some models with high speeds the restrictions are even higher – up to 50 g / m3. Good models have several (up to 10) impellers, the on/off of which regulates the flow rate.
Which brands to prefer
When choosing a specific brand of pump for a well, pay attention to two things. The first is the number of positive and negative reviews. Only here it must be borne in mind that positive reviews are rarely written – if the equipment works about it and is not remembered. Only if before that there were some problems that the new pump solved. Then there are chances that there will be positive feedback. You are much more likely to receive negative feedback if there are problems. So the ratio of positive and negative opinions will be biased. You can simply compare the amount of positive and negative relative to different brands.
The second thing you need to pay attention to is the availability of service centers and warranty workshops in your region. So that if a problem arises, it can be quickly and easily solved, and not go to distant lands. This is also very important.
What to look for (except technical specifications)? The presence and number of degrees of protection. Good (and expensive) equipment may have the following built-in mechanisms:
- dry running protection (shutdown in the absence of water);
- protection against overloads and electric discharges (against overheating);
- sand cleaning system;
- from water leaks (check valve, here you can put it without any problems additionally).
From this list, it is very desirable that the well pump has protection against dry running and overloads. These are the basic things that extend the life of the unit. Sand removal is, of course, good, but the equipment is very expensive. A non-return valve can be placed immediately at the pump outlet on the suction hose (pipe).
Pump brands that are considered the best
The opinion of experts does not always coincide with the opinion of users, but it is also worth listening to them. They recommend mostly expensive brands, but not just like that, but because they really work well. So, here is a list of firms that the pros trust:
- Aquarius. At a relatively low price, quite decent quality.
- Gilex. They work normally – about 5-6 years – with the right selection of parameters.
- Flow. Chinese-Russian, but they work fine.
- Aquario (Aquario). Normal quality for not very big money.
- Grundfos (Grundfos). The leader in quality, but also in prices too.
- DAB. Worthy competitors for Grundfos at lower prices.
- ESPA. Good quality. There may be problems with service – not all regions have service centers.
- Willo (Willo). Another one of the market leaders. Good quality at more or less decent prices.
- ZDS. These well pumps performed well. The manufacturer gives them a 2-year unconditional warranty – replacement in case of breakage for any reason.
- Acua. All hydraulics are stainless steel, but these pumps are not sized for most wells.
- Water cannon series Prof. Quite decent quality, but only repair in the service center.
This is a more or less complete list of brands that professionals recommend.