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How to extend life of your submersible borehole pump

Submersible well pumps are a great solution for drawing clean groundwater, regardless of its source (wells, boreholes, retention tanks, etc.). A well-chosen submersible pump provides a constant supply of water while maintaining low costs and high pump reliability. However, it is important to choose a pump that matches the conditions of your borehole or well.

Submersible water pumps have been specifically designed for long-term immersion, they guarantee easy installation and almost maintenance-free operation for many years. We recommend choosing a pump that has built-in protective features, such as a Grundfos submersible well pump. The pump takes care of everything needed for you and there is no need to purchase additional accessories. However, you can extend the life of even the best submersible well pump by providing it with excellent conditions.

How to extend life of your submersible pump?

Regular cleanlines control

Submersible pumps are intended for pumping clean water. In general, the more sandy material and other abrasive substances present in the water, the sooner your pump wears out, so it is important to clean new or dirty wells an boreholes. For each well pump the allowed amount of solid particles is given by the manufacturer.

So you should not forget to regularly check your well and ideally clean it every 5 years. This not only ensures a smooth operation of your submersible pump, but also purity of the pumped water.

In order to achieve the best quality water from your well, we recommend installing a cold water home filter, which also protects your appliances.

 Ponorné vibrační čerpadlo pro čištění vrtů Malyš Ruche

Beware of a lack of water in your well

Submersible well pumps work submerged in a dynamic water levels and it is necessary to ensure that the water never drops below the level of the pump. The pumps should be suspended deep enough in the well. If the water level falls too much, the submersible pump may run dry and get damaged.

The solution to this is to get a probe for water level monitoring or a pump that already has built-in protection against dry running (for example, Grundfos SQ and SQE submersible well pumps) and can stop it in time if there is a lack of water in the well.

Correct submersion depth

It is very important to install your submersible pump at the correct depth not only as prevention against dry-running, but also as protection against damage to your pump due to high water pressure. When submersed at a greater depth, the water column exerts a higher pressure on the pump, which then affects its tightness. If the pump is immersed to a greater depth than it is designed for, internal parts of the pump may be damaged by water seepage.

If there is a lack of water in the well, it is possible that it has not been installed at the correct depth. However, before lowering the pump deeper into the borehole, first double-check the correct submersible depth for your pump. An insufficient amount of water can also be caused by a low well capacity, so it is necessary to find the cause first.

Nerezové lanko pro zavěšení ponorného čerpadla

Well pump cooling

Cooling the submersible pump is another reason why it is important to pay attention to the water levels in your well. Sufficient water flow around the pump (at least at a speed of 0.15 m/s) provides it necessary cooling, so that the motor does not overheat. The optimal space between the pump coat and the borehole wall is at least 10 mm and this limit also serves as protection against mechanical damage.

If it is not possible to ensure the necessary cooling by water flow, the same effect can be achieved by installing a cooling jacket.

Voltage fluctuations in the network

Well pumps operate within a certain voltage range. However, the voltage in the network is not always constant and fluctuates, which can result in more frequent pump shutdowns and engine damage.

The Grundfos SQ and SQE submersible well pump is fitted with a frequency converter unit and operates in a wide range of voltages, therefore it is able to ensure a stable supply of water even during voltage fluctuations.

Ponorné čerpadlo do vrtu Grundfos SQE

Frequent turning on and off of yor submersible pump

Frequent starting and stopping of a submersible well pump, whether due to inadequate voltage or due to lack of water, overloads the motor and pump contactors, which significantly shortens its life. For each type of well pump there is a recommended maximum number of starts, which should not be exceeded for the sake of its protection. On the other hand, it is also not a good idea to leave it switched off for a long time. The submersible pump motor needs to be started at least once a year to prevent seizing.

Electrical and mechanical load on your pump

Inadequate cooling, fluctuating mains voltage, frequent starting and stopping and long-term operation of your pump at maximum flow all lead to high electrical and mechanical stress, resulting in faster wear and shorter life. It is important to minimize all these negative factors for smooth operation. Your pump must be chosen so that is closest to the point of best (peak) efficiency, while at maximum flow it should operate only minimally.

If you consider buying a submersible water pump, choose a pump whose built-in features automatically contribute to lower electrical and mechanical loads. You will be rewarded with a longer service life and lower operating costs.

Chladící plášť pro čerpadla do vrtu Grundfos

What about winterization of you well pump

You can use a submersible water pump all year round if conditions for its operation are met. However, if you do not use this water source during winter, it is necessary to winterize the submersible pump along with winterizing the bore or well.

Submersible borehole pumps are not frost-resistant, so to winterize, unplug them from electricity, pull out of the borehole/well, drain and store in a safe place where they cannot freeze. Then carefully winterize the water source itself so that it does not become polluted due to torrential rains and melting snow, even if it only serves as a source of domestic water. Large quantities of sandy material and other abrasives in the contaminated water could damage your pump when restarted. If you are not sure about the quality of your water, it is better to have it analyzed before the season or clean the well as a precaution.

Regular maintenance

Regular submersible pump servicing is an excellent way to make sure that your pump is always in top condition. It also includes replacement of worn parts (especially sealing). The frequency may vary depending on flow rate, presence of solids and well conditions, however it is generally recommended that a submersible pump should be serviced every 3 years.