Prime a Water Pump

Water pumps will run out of pressure and stop working if turned off for an extended period of time, such as over the winter. In order to get the pump working again, it needs to "primed": water needs to be flushed back into it and forced through in order for it to create enough pressure to begin pumping again. Although methods vary slightly for different types of water pumps, the steps below will show you the basic steps of how to prime a water pump.

Steps

Prepping the System

  1. Turn off electrical power to the pump. No device should be left on if you're fiddling with it. Go to the base of the pump and make sure it's turned off.
  2. Locate a plumbing fixture that provides access to the pump system. On a pool pump, this will be the strainer basket. If you're not working with a pool pump, use whatever fixture is closest to the water tank.
  3. Prepare a hose that can be connected to an independent water source. This will flush the hose to remove any build-up and ensure you have clean water.
    • Many people choose to use their garden hose or their washing machine hose connected to their garden hose. However, if your garden hose contains lead, know that you shouldn't drink from it. If you're using this for a well, be sure you have a way of filtering the water after it's through the hose.
  4. Flush the hose to remove any build-up. Run water through it, keeping a constant stream for a few seconds before you shut it off. This is especially important for hoses that aren't routinely used or haven't been used yet this season.
  5. Open any relief valves on the pump system. This will keep pressure from building up. Watch your water pressure gauge to make sure all is going according to plan.

Flushing the System

  1. Insert the hose in the plumbing fixture. On a pool pump, place it in the strainer basket. If you're priming a water pump for a building, just connect it to the fixture nearest the water tank. You now have a source of water flowing into the new building or pool.
  2. Turn on the water to the hose. At the beginning, you'll hear air flowing through the system. This is normal.
  3. Wait for water to enter the tank. You should hear water filling the tank or, if you have a water pressure gauge, notice the level rising. On a pool pump, fill the strainer basket and close its lid.
  4. Turn off the water to the hose. Once you see water coming out the opposite end, you can turn off the turn off the water to the hose. This should take but a few minutes.
    • When the water stops flowing on the opposite end (where you're trying to get the water to), the water system has been pressurized.
    • However, don't disconnect the hose, just in case you end up needing to repeat the process.

Finishing the Job

  1. Restore power to the pump and turn on the pump system. Allow it to run for about a minute. Do know that the pump might not run if the water tank pressure is at or above that pump's cut-out pressure. if it doesn't start, that's why.
    • If you have opened relieve valves, wait for water to begin seeping from them and then close them.
  2. Wait for the pump to finish its cycle. If it turns off naturally, it is primed. If not, you need to prime again. Try turning the water on at the recipient source. If you hear the water pump turn on, you're good to go.
  3. Repeat all steps until the pump is primed and functioning normally. In certain circumstances, you may need to repeat this once or twice more.
    • If you have a water tank that is the steel bladderless type, try leaving the tank drain open at the start of the procedure. This way incoming water can enter the tank by pushing air out of the drain. However, when you see water coming out of the drain, close it.



Tips

  • When priming a pool pump, you may want to prime the pool skimmers first and then the main drain. This can be accomplished by turning the diverter valve first to the main drain indicator, shutting off water to that section, and flowing water through the pool skimmers. Next, turn the diverter valve away from the main drain indicator so that both it and the pool skimmers are open, and wait for water to flow normally.
  • Your goal in priming a water pump is to restore pressure so that the pump can pull water itself. Check your pressure gauges periodically and, if the pressure is not high enough or the pump is not working adequately, repeat all steps. It's normal to make a few attempts when priming a water pump.
  • If you cannot locate a plumbing fixture (Step 2), you have may a simple pump system that requires you to make your own intake valve. This can be made with a tee fitting, clamps and some pipe, and should be installed near the water source.

Warnings

  • Keep a close eye on your pressure gauges throughout. Keep release valves open longer than you think you might need to. It's better to let pressure escape than have it build up to dangerous levels, which can cause permanent damage to the pump system.

Things You'll Need

  • Water pump
  • Garden hose
  • Independent water source

Related Articles

Sources and Citations