Replacement of the well pump with your own hands

At some point, submersible pumps that are employed in self-sufficient water supply systems will need to be taken out from their source for routine inspection or repairs, even if they are operated correctly. In certain instances, the pump may malfunction entirely and necessitate a replacement in the well. However, it is important to note that performing this operation can be quite challenging in some cases.

When you need to replace the well pump

• The motor of the unit may have burned out, causing the blades to move (in the case of a diaphragm submersible, the electromagnetic coil may stop working);
• Choosing the wrong pump for a specific well in terms of power and capacity;
• Damaging or burning out the cable that supplies the equipment;
• The well may become silted or filled with sand;
• Breaking the cable that holds the pump in the well;
• The pressure pipe connected to the unit may fail;
• The appliance may fail due to improper installation;
• The productivity of the equipment may decrease;
• The unit may get stuck in the well due to the electric cable being wrapped around it, etc.

Dismantling of the old pump

Replacing the well pump, also known as extracting it from the well, can be a challenging process, despite its apparent simplicity. The difficulty of removing the equipment depends on the depth at which it is installed. Specialists typically classify the lifting of pumping equipment into three levels of complexity.

1. Lifting the device from a depth of up to 30 meters is the easiest option for removing the pump. In this case, the weight of the unit, along with the connected pipe, is minimal. Even one person can handle the removal of such equipment from the well.
2. Retrieving equipment from depths greater than 100 m is typically accomplished by connecting galvanized or stainless steel pipes to the depth unit. In some cases, HDPE pipes capable of withstanding a pressure of 16 atmospheres are used in place of metal pipes. Ultimately, the equipment is quite heavy, making it necessary to use a crane or winch to remove it from the artesian well.

The procedure for extraction is relatively straightforward:

• Disconnect the equipment from the power supply.
• Disconnect the pressure pipe from the water supply system of the house.
• Slowly and carefully pull out the pump (using a rope) and disconnect sections of the extracted pipe if it is made of metal.

Problems during disassembly

However, there are times when it becomes impractical to uninstall the equipment due to a range of issues.

Pump silted up

Siltation of the casing pipe due to infrequent use of the source water pump is a prevalent issue encountered when attempting to extract the unit. The accumulation of silt within the casing forms a barrier, impeding the removal of the unit from the well.

To extract the equipment from the casing, the technique of rocking is employed in this instance. The method involves vigorously moving the pump up and down, which effectively flushes the surrounding area with water and eliminates any built-up debris.

It is crucial to exercise patience during the pumping process in order to achieve thorough flushing. The cable should also be pulled with moderate force to avoid complications such as the device becoming stuck in the pipe or the rope breaking.

If rocking fails to free the equipment, the assistance of firefighters may be required. They will lower a fire hose near the pump and utilize a powerful water pressure to erode the layer of silt that has accumulated.

If the unit is stuck in a well drilled in limestone, lime scale on the casing could be a potential reason for the equipment getting stuck.

Here’s a helpful tip! When faced with this situation, you can employ a rocking technique while the engine is running to extract the appliance. This will allow for a more thorough cleaning of the casing.

Many times, when removing lifting equipment from the borehole, it gets stuck inside the casing due to slack in the electric cable or cable itself. The cable (rope) wraps around the casing tightly, preventing the equipment from moving freely. To resolve this issue, the pump can be "freed" using the following algorithm.

1. First, try lowering the unit back to the bottom of the borehole. Then, slowly swing the cable in different directions while pulling it up to unwind the loop formed around the unit.
2. When lifting the unit, make sure to simultaneously pull up all elements connected to the pump, including the hose, cable, and rope.
3. Secure all elements with clamps, placing them every meter.
4. Lift the equipment gradually and with utmost care.

Pump fell down the well

If the unit has fallen into the well while extracting it, it may not always be possible to retrieve it. However, it is definitely worth attempting to do so.

1. Create a makeshift "cat" hook using a piece of steel wire.
2. Attach a length of steel wire to the hook, ensuring it is the same length as the well’s depth plus an additional 50 cm.
3. Gently lower the hook into the well and, once it reaches the fallen pump, begin rotating the wire in an effort to catch onto the hose.
4. If successful in hooking the hose, carefully and slowly pull the unit out of the well. A winch or other lifting equipment may be used for assistance.

In situations where the pump cannot be removed, it can be left in the well as long as it does not impede the water filling process. In some cases, the irretrievable unit can be broken down using a chisel (see figure below).

The unit can be disassembled into smaller components and taken out one by one or left inside the well.

Another option is to contact drillers who can use a specialized drill to restore the well’s functionality. It’s important to note that this procedure can be expensive, but it is still much more cost-effective than drilling and setting up a brand new well. Additionally, once the well has been cleaned, it will be necessary to replace the depth pump with a new one.

Before you begin the installation process of a pump in the well, it is important to make the necessary preparations for the casing pipe.

1. Start by cutting off the top section of the casing pipe using a bolt cutter. Make sure that the pipe extends about 20 cm above the ground level.
2. Then, place the lower part of the casing head onto the casing pipe and insert the sealing ring on it.

Once the casing pipe is ready, it’s time to prepare the pump unit itself. Test the pump’s functionality by submerging it in a container filled with water.

It is crucial to understand that checking the equipment without immersing it in water, also known as "dry" checking, is strictly prohibited. Even a brief moment of operation without proper submersion can result in irreparable damage.

Next, attach the cable to the device. This cable is necessary for lowering the equipment into the well or, if needed, pulling the pump out of it. Typically, a stainless steel or plastic-coated rope is used for this task. Alternatively, a safety cord made of kapron can also be employed. The breaking strength of the cable should exceed the weight of the equipment by at least 5 times. The rope is threaded through designated holes located at the top of the device, and then secured with metal clamps to form a loop.

Attach the fitting to the unit in order to connect the pressure pipe.

Secure the power cord and cable (without applying pressure) to the pressure tube using plastic clamps. Then, gently lower the unit into the well while grasping it by the safety cable. At least one person should be present for this procedure.

Suggestion: Lower the device gradually, ensuring that the electrical cord is neither pulled tight nor drooping.

Once the equipment has been submerged to the predetermined depth, the next step is to place the upper section of the casing head onto the casing pipe. Before doing so, make sure to connect a safety cable to the casing head.

Join the condenser box to the electrical cable originating from the unit.

Start the unit and observe its performance for 30 minutes. The water may appear cloudy initially, but it should clear up after a short while. If no issues arise during the pump test, you can proceed with installing the unit.

Trim the pressure pipe at the well head to the appropriate length (with a little extra) and attach a fitting to connect it to the above-ground (or underground) pipeline system. The final step of the unit installation involves sealing the power cable in a waterproof conduit.

Installation of the depth unit is now finished. Afterwards, you have the option to connect either a storage tank or a hydroaccumulator, along with a pressure switch, to the pipeline. By doing so, you will create a fully functional pumping station capable of supplying uninterrupted water to the water supply system of a private household.