The pump is an integral part of the swimming pool filtration system. Most residential swimming pools are expected to have enough pumping capacity so as to turn over the total volume of the pool in every six hours. In an average swimming pool, this means a circulation of 36 gallons per minute. This is quite a heavy load on the pool pump and other components in the system.
When your pool system is completely primed, the system components, pump, filter and pipes are filled with water and the pool pump is able suction water from the pool and gets it back into the pool via the return. Priming a pool pump involves pushing air from the pumping system and then filling the pump and water lines with water. Depending on the level of water in the suction side of the lines, you will have to follow a number of steps. If you are putting up a new pool system, it means there is no water in the lines and you may be required to repeat the steps several times. However, if you are replacing or adding components into the pumping system such as the heater, chances are that there will be water in the line and priming will be a lot simple.
This guide on how to prime a pool pump infers that your pool has no or little water in the system. You can tell there is low water or no water at all can by reading the pool filter pressure gauge.
A pool pump is usually installed underneath the upper water level of the pool in pump pits or in compartments that are underground. When the pump is turned off, water gets to the pump outlet through the gravity. When the pump is energized, the inlet line is usually under suction while the pump outlet, the filter and the return line to the pool is under pressure. If anything interferes with that, then there is no circulation even when the pump is operating physically.
What you will need
o-rings and covers
How To Prime A Pool Pump
You will need to turn off the pool pump if it is running. To be completely secure, you should switch off the power at the circuit breaker to the motor.
The suction diverter valve lets you switch off the water from the main drain or the skimmers. Both of them cannot be switched off at the same time. To prime the system properly, you will need to move the diverter valve so that the offside of the lever points to the main drain side. This way, water will only flow from the pool skimmer lines. However, if you are simply adding a part to an already functional system, the lines will still have water and you can probably re-prime the system by opening the main drain and skimmer simultaneously(the lever is located in between the main drains and skimmers).
The next thing will be to free pressure from the water lines and pool pump. To free up pressure, rotate the air relief valve located at the top of the pool filter anti-clockwise. You may feel air getting released since you can see the pressure on the gauge move from 0 to psi. Let this relief valve remain open.
Leave the lid to the pool pump strainer box opened. To open the strainer box, you can either turn the 2 knobs that are found on the strainers lid anti-clockwise or swivel the knobs down in the opposite direction of the lid.
NB: There are some strainer lids that are fixed with a screw instead of knobs. In such a case, you will only need to twist the lid anti-clockwise to get the lid off the top of the strainer box.
Carefully pull out the pool pump strainer and clean any debris that may have built up over time. When done, put the basket back in place. Using a bucket or a garden hose, fill the pool pump strainer box with enough water. Cover the strainer with the lid carefully for a tight seal. Secure it with the hand only. If your pool pump has knobs, fasten them equally with the hands. Avoid using any tools to tighten the lid.
Check that the diverter valve to the pool return is set to open. This allows the pool pump to easily discharge water to the pool. If its covered, too much water pressure that builds up when the pump is operating will likely damage parts of the pumping system and it could also be dangerous. Turn your swimming pool pump power on again.
Check how water is flowing through the strainer box. There should be free flow of water in 30 to 60 seconds. The air relief valve should not be closed yet. Since there will be pressure build up, air will be getting released through the relief valve. When water begins splashing out of the valve, rotate the valve clockwise so that you can close it.
If the water is not flowing freely in 30-60 seconds, you will need to repeat the above process. Sometimes you may have to repeat these steps several times so as to push out air from the line.
When water begins to flow through the pool skimmer lines, open the main drain line slowly at the delta valve. To allow air to escape from the main drain line, open the relief valve. The water should flow within 30 to 60 seconds. Shut off the relief valve. If there is no pressure build up on the pressure gauge and a full strainer box, then you may need to repeat the above steps.
When the system is completely primed, change the diverter valve halfway in between the skimmer and main drain to enable regular operation.
If even after several attempts you still cannot prime your pool successfully, then your system may have serious blockage or leak. You should try and resolve the problem before you prime the pool pump again.