How To Prime a Pool Pump

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When a pool pump is priming, it is purging the plumbing system of air to create a vacuum effect to pull water from the pool, push it through the filter and back through the return line. An inground pool pump should be able to prime itself under normal circumstances. But if you have had to de-pressurize the system for maintenance, i,e, pump motor replacement, cartridge cleaning,  manual priming is helpful to give your pump a head start for priming.

Things You'll Need

Video

Step by Step

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Step 1

Turn off power to your pool pump at the circuit breaker.

Step 2

Make sure your pool’s water level is at least halfway up the skimmer face. Also, remove debris from the skimmer’s strainer basket.

Step 3

A suction side diverter valve allows you to select whether the pump will pull from either the skimmer, main drain or both. Use the valve to close either the main drain or skimmer line to that the pump is only pulling from the other line. We do this to concentrate pump’s suction, to increase the efficiency of the priming cycle.

Step 4

Open your filter’s air relief valve to allow air to escape as we manually prime the pump. You may hear the noticeable hiss of air passing through the valve when you open it, and after the pump is turned on, this is normal. Sand filters may not have an air relief valve, but rather an internal air relief tube which releases pressure automatically.

Step 5

Remove your pump’s strainer lid. To open up the strainer box, 1-turn the two knobs on top of the strainer lid counter-clockwise and 2- swivel the knobs down away from the lid. Note: Some strainer lids screw on instead of having knobs. In these cases twist the lid counter-clockwise to remove the lid off the top of the strainer box.

Step 6

Remove any debris from your pump ’s strainer basket to improve the pump’s suction during the priming process.

Step 7

Fill your pump’s strainer with a hose or bucket until the water sits above the pump strainer’s intake port. Filling to this point ensure the suction pipe is purged of air.

Step 8

Reattach the pump’s strainer lid. You may want to add a new coat of lube to the pump lid’s o-ring to increase the o-ring’s longevity and prevent any future sucking air leaks.

Step 9

Make certain that any valves on the main return line are open. This will allow the pool pump to discharge water to the pool. If this is not open, excessive water pressure that builds up during pump operation may damage parts of the pumping system and may be dangerous.

Step 10

Turn on the pool pump breaker, then turn on the pump.

Step 11

Keep an eye on the pump’s strainer lid to ensure water is flowing. After the initial water, we used to prime the pump flushes through the system, water should begin to freely flow and fill the pump’s strainer basket. If after a minute, water still has not begun to fill your pump, restart from step one in this guide, and if the problem persists, read this guide: How To Determine Why a Pool Pump Won't Prime

Step 12

The air relief valve should still be open. As the pressure builds, air will be released through the relief valve. When water starts to spray out of the valve, turn the valve clockwise to close it.

Step 13

After the pump has primed itself, reset the suction side diverter to pull from both the main drain and the skimmer.

Step 14

If water isn't flowing freely in 30-60 seconds, repeat steps: turn off the pump, bleed off the pressure, reopen the strainer, refill the strainer, and close the lid. Then turn on the pump. You may have to repeat these steps several times to purge the air from the line.

Step 15

When water is flowing through the pool skimmer lines, slowly open the main drain line at the diverter valve. Open the relief valve to allow air in the main drain line to escape. Again water should flow freely in 30-60 seconds. Close the relief valve. If you don't see pressure building on the pressure gauge and a full strainer box, repeat steps 1 -10.

Step 15

If, after repeated attempts, you cannot prime the system successfully, your system has a major leak or blockage. This problem must be resolved before you can prime the swimming pool system.

Step 16

As stated earlier, if  after a minute or attempting to prime water still has not begun to fill your pump, or after your reset the suction diverter valve the pump loses prime, restart from step one in this guide, and if the problem persists, read this guide: How To Determine Why a Pool Pump Won't Prime and How to Identify and Correct Air Leaks 

 

Comments

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(81 to 120 of 143)

InyoPools Product Specialist  Posted: 6/23/2013 

Frank - Here's a link to some common pool system configurations: Plumbing Schematics.
 Reply

 Posted: 6/20/2013 

you keep mentoning the different valves like the diverter valve and the position it should be. but I dont know which is which. Please can you give me a diagram so I know which one is which valve and their positions.
 Reply

InyoPools Product Specialist  Posted: 6/19/2013 

TR - Three thoughts. 1- It is not uncommon to have an initial pool pressure of 6 psi on a new system. However, if you have the same filter, I would have expected that the psi would be closer to what it was before you changed the pump. 2- You may have had some resistance in the heater lines that was removed. 3- You may have a smaller “1 HP” pump. Real or Total HP (THP) is the product of HP and SF. Check the labels on your motors. If your old motor had a HP of 1.0 and a SF of 1.65, its THP was 1.65 HP. If your new motor has a HP of 1.0 and a SF of 1.0, its THP is 1.0.
 Reply

 Posted: 6/18/2013 

Just repaced my old Pool Pump yesterday with a brand new 1 HP pentair pump...Pool heater had gone so the pool tech looped the in/out lines together so that we could remove heater until replaced..Pump started and it seems to be working fine except that the pressure is around 6 PSI..Pool guy says that a new pump with a clean filter should read between 5-10 PSI...I always thought that it should be around 12-16 PSI...I notice a few bubbles in the return line...OLd pump didnt have this...Any ideas?
 Reply

InyoPools Product Specialist  Posted: 6/9/2013 

TTFNWEN - If your pump is maintaining prime and your filter gauge is showing little or no pressure, I suspect that your pump is undersized. As a gross benchmark, we usually recommend a pump of 1 to 1 1/2 HP for a typical in ground pool. I have noticed on a two speed pump, when you use the low speed and reduce the HP by half, the pressure gauge can show 0 or very low psi. Your pump might be undersized by 2/3 to 1/2 the needed HP. Have a pool professional do a pool system analysis for you.
 Reply

 Posted: 6/4/2013 

I have an inground pool. My pump is NOT drawing water from the skimmer. I have checked the impeller and it is clean and turns. However, I have noticed the glass backwash indicator is not filled with water. I suspect my filter is not full of water and my pressure gauge does not work. Can this be the cause? I have used a shop-vac to test the lines and it draws water, so I don't there's a blockage on the suction side. Also, only one of the returns is working and not very strong.
Thanks

 Reply

InyoPools Product Specialist  Posted: 6/2/2013 

doityursel - If your pool was very dirty when you opened it up, you may have clogged your filter especially if your added chemical to help clear it up. When possible, that water should bypass the filter and go out a waste line. Try backwashing or cleaning your filter a number of times as you are filtering to the point that your water is clear. Also check your pumps impeller to see if it was clogged. See "How To Clean Out a Pool Pump Impeller"
 Reply

 Posted: 5/31/2013 

After opening for the summer, the pump started fine and ran very well for at least thirty minutes. My son vacuumed for another thirty minutes (into the skimmer basket), and started to lose prime. I don't think he pulled the vacuum head out of the water or it would have died immediately. Water flow got weaker and weaker. Finally lost prime altogether. Now I can't get it to prime again. Starts for a minute then the flow turns to a trickle and dies. Thinking I have an air leak or a bad seal? Any other obvious possibility I'm missing? I don't see how I could have a blockage. Help would be greatly appreciated.
 Reply

InyoPools Product Specialist  Posted: 5/27/2013 

sc - Make sure the pressure is off the system by releasing the pressure valve or opening up your filter. Then it's going to be brute force. The cover is on too tight. Try having two people twist it and twist it counter-clockwise. If you can find a strap clamp that large, that may help. When you do get it off, put lubricant on the O-ring to make it easier the next time. Hand tighten.
 Reply

 Posted: 5/26/2013 

i cant get the cover off of my sand filter model hayward powerflo matrix,The basket is filled with debris and i cant get to it to clean it
 Reply

InyoPools Product Specialist  Posted: 2/4/2013 

alefty27 - A non-self priming pump can only be used on an above ground pool because the pool's water level is above the pump and water can be fed into the pump by gravity. If your pool is in-ground, this pump will not work with your pool. Your pump is not designed to suck water from a level below the pump.
 Reply

 Posted: 1/30/2013 

have an old pool w/single main drain just replaced pump w/ old but working non-self priming pump,there were no jandy valves just 2 lines one for suction & one for return & filter has bleed lines on bottom can someome please tell me how to get this thing primed conventional methods not wking
 Reply

InyoPools Product Specialist  Posted: 9/26/2012 

Dale - You are correct. An above ground pool pump only works because the pool's water level is above the pump and water can be fed into the pump by gravity. These pumps are not designed to suck water from a level below the pump.
 Reply

 Posted: 9/24/2012 

I have read some comments about priming a pool pump. I have been trying to use my old above ground pump,to pump water for my new waterfall and pond. So is it correct that I can't use an above ground pump to pump water up from the pond. I don't have any suction or lift from the pond,however it does push water out. I have two pumps one from my old pool and one from my old spa. They both work great but no lift.
 Reply

InyoPools Product Specialist  Posted: 9/2/2012 

JMP - Here are some common problems that lead to low pressure: clogged skimmer box, clogged strainer box, clogged impeller, some suction side valves closed off. See our how to guides for correcting many of these problems.
 Reply

 Posted: 9/1/2012 

My pump is running at about 6psi and bubbles are coming out of the returns. It always ran about 15psi. T he pool is clean and water tested perfect but I still feel the air bubbles are not good.I released the air on the top of the pump already, replaced pressure valve, old one was reading 0. So what do you think? I have a challenger 2hp pump and a headache, I know my pool.
 Reply

InyoPools Product Specialist  Posted: 7/31/2012 

Jolli86 - If your pool is only half full, you have to close off the skimmer(s) and the suction line port if you have one, and only pull water from the main drain. Otherwise you will be sucking in air through these top ports and your pump won't prime. If you have shut these lines off and still can't prime your motor, you have a leak in a suction line up to the pump.
 Reply

 Posted: 7/28/2012 

I have a self-priming pump that doesn't seem to be priming itself. Should I be able to prime it manually, or is there a reason that my basket bowl isn't filling up? P.S. The pool is only halfway full.
 Reply

InyoPools Product Specialist  Posted: 7/9/2012 

jeanne - I would check for leaks in you system after the pump. You should see water spraying out or dripping. When the pump is off, these leaks would allow the water on the suction side of the pump to drain back into the pool requiring you to prime the pump every time you start it.
 Reply

Anonymous  Posted: 7/8/2012 

Water will not return to pool. I used these steps yesterday to prime the pool pump and it worked great and pool ran 8 hours. When cycle started again this morning I am having same problem and have to prime again. Water will not return to pool and is blowing out the DE filter. Why does this keep happening?
 Reply

InyoPools Product Specialist  Posted: 6/29/2012 

bgg1 wrote back the next day - "Found the problem - a small pinhole leak in the intake pipe. Patched it up and good to go!"
 Reply

 Posted: 6/27/2012 

I have an old Anthony pool. New Hayward pump and having trouble priming. Runs for a couple of minutes then I just get air.
There is no diverter valve! The previous owners left a clear plate with a hole and plug that goes in the skimmer for hooking up the suction for a Kreepy Krauly. Does this need to be in and plugged?
Thanks.

 Reply

InyoPools Product Specialist  Posted: 6/23/2012 

puzzeled - Check for leaks on the suction side of your pump. See out guide for checking leaks. Check to make sure your impeller is not worn or clogged with debris. Make sure your filter is clean or backwashed. It may be time to replace your cartridge or filter media.
 Reply

 Posted: 6/21/2012 

my pool pump is reading 20 but the pressure is not good . its not sucking in the water to clean it like it should be
 Reply

InyoPools Product Specialist  Posted: 6/4/2012 

karen - Often times you cannot fill your basket bucket full with a hose. It runs out through the pipes. But filling the pipes should provide you enough water to prime the pump when you turn it on. If it doesn't prime, you have a leak on the suction side of the pump.
 Reply

 Posted: 8/3/2019 

My pump is primed and basket is full but when I turn it on pump sucks water out of basket and doesnt fill back up. Help?
 Reply

InyoPools Product Specialist  Posted: 8/7/2019 

How To Determine Why a Pool Pump Won't Prime
 Reply

 Posted: 6/3/2012 

my pump strainer basket will not stay full of water...even when i put a hose in it will not stay full. any suggestions
 Reply

InyoPools Product Specialist  Posted: 5/31/2012 

jbrightowl - all Above ground pools pumps are non self priming because the water level is above the pump and gravity dumps the water into the pump. Pumps for in ground pool are self-priming because they are above the level of the pool and must suck the water into the pump. A timer can be used with either type of pump.
 Reply

 Posted: 5/28/2012 

how do i know if i have a self priming pump or not? if i don't then putting the pump on a timer is not an option, right?
 Reply

InyoPools Product Specialist  Posted: 5/15/2012 

JBB – At this point you have to pull water from the man drain. Make sure that your valves to the skimmer(s) and suction port are closed so that you aren’t sucking air in through those ports and loosing prime. You may have to fill the strainer basket for 5 minutes to fill up the main drain piping.
 Reply

 Posted: 5/14/2012 

I was draining the pool to paint it. I stopped about halfway through to make a concrete repair. Now it will not reprime to start the draining process again. What should I do?
 Reply

InyoPools Product Specialist  Posted: 5/6/2012 

lakersfan - Check that your diveter valve for the main drain is open. You should be able to hear and feel the water going thru the valve when you switch from off and on. If the valve is working, you may have a block in the line from the main drain to the pump. You may have to hire a professional pool man to correct that problem.
 Reply

 Posted: 5/6/2012 

emily - Yes the pump can be primed from th main drain, but you will have to temporarily seal off the skimmer line to the pump so it doesn't suck in air.
 Reply

 Posted: 5/5/2012 

i have a problem with main drain not functioning? all chemicals sits at bottom of pool! yes,it is a inground pool.please help!!!
 Reply

Anonymous  Posted: 5/5/2012 

I have an in ground pool in the process of replacing skimmer line......Can pump be primed from main drain?
 Reply

InyoPools Product Specialist  Posted: 5/5/2012 

TALJONICK - First check that you have a in ground pool pump. Aboue ground pool pumps are not designed to work for an ingound pool system. Then check for leaks in your suction side, between the pump and the skimmer. See our guide on How toTo get rid of Bubbles in your Pool.
 Reply

 Posted: 5/4/2012 

I HAVE A IN GROUND POOL CAN NOT GET PUMP TO PRIME AND PUMP....
 Reply

InyoPools Product Specialist  Posted: 3/28/2012 

INA - Hard to tell without being there but a couple of suggestions: The pump can never run dry or the shaft seal will go and spray water on the motor. Make sure your water level never goes below half way down the skimmer opening. Check that you always have prime when the motor is running. Also check your power source over time. If you are wired for 230V and your source power is constantly dropping below 210V, that will ruin your motor over time. If these suggestions don't help, call in a pool professional to look at it.
 Reply

 Posted: 3/28/2012 

Oh ok thanks, that is good to know.. What could be the problem? I've tried everything!
 Reply