Pool Pump Won't Prime? Here's What You Need to do

If your pump will not prime follow this checklist to eliminate the potential causes one by one. While this list of possible causes is fairly comprehensive it is not exhaustive and there are a few rare circumstances that exist which a typical homeowner will not be able to diagnose such as a break or leak in an underground line.

(Remember, just because you may be able to get the pump running does not mean that the pump, plumbing, or electrical equipment is working correctly.)

  1. Make sure the water level in the pool is high enough so it can flow into the skimmers.
  2. Make sure the skimmer doors (also called weirs) are not stuck or hung up. This will obstruct the flow to the skimmers. (These first 2 steps account for 90 percent of pumps that won’t prime.) Occasionally skimmer doors or weirs hang up due to waves or they can hang up if the filter were to have air trapped in the top of the tank that decompresses when cycled off causing water to rush backwards through the lines.
  3. Make sure the valve handles are screwed on tightly. If you have a Jandy or Compool valve with a small threaded tab at the top be careful not to over tighten the tab as they are prone to breaking easily.
  4. When you turn on the pump does it just hum? If so there may be electrical problems. You should call a pool professional to test the voltage on the pump, ensure the shaft is free, and potentially test the capacitor(s) to diagnose the problem unless you are familiar with these inner workings of a motor and are willing to undertake disassembling the pump and resealing it.
  5. If you have an Intermatic timer mechanism, can you see the gears turning? The most common and oldest style of Intermatic timer is commonly referred to as a yellow dial timer. On those types of timers if the dial pointer is directly over the “off” lug it can prevent the tab hanging down from fully moving to the Right when a user attempts to turn on the timer manually for the pump to run.
  6. If you have an Aqualink or Aqualink RS control center (as well as some Gold Line and Compool varieties) listen when you push the button to power on the pump… do you hear a click? If not you may have a damaged power board or relay out on the control center. Is there power at the equipment when you turn on the other equipment? Sometimes a breaker or GFCI has popped. Sometimes a main power switch (often looking like a light switch) has been turned off.
  7. Check the pump lid and pump lid o-ring and make sure they do not have any cracks from age. Lubricate the pump lid o-ring and ensure it is clean.
  8. Make sure there are no cracks, chips, or breaks in the pump basket. If it is a Pentair (previously Pac-Fab) Challenger pump, and it has a factory pump basket with a black handle, make sure the handle is on the attached to the basket . The black handle needs to be snapped onto the basket on both sides so it does not move up and down. Make sure that the basket is lined up with the internal grove and seated fully down into the pump basket pot area.
  9. Fill the pot with water, screw on the lid and turn on the pump.
  10. Open the filter air relief valve while the pump is trying to prime.
  11. If you have a SPA you can adjust the water flow to suck from the SPA drain. (Make sure to change the valve back to the correct position once you are finished either attempting or priming the pump. This can be very helpful if the spa and or the equipment is elevated above the pool water level.)
  12. If the pump is still not priming see if you can see any leaks around the pump and plumbing. Is the plumbing going into or out of the pump loose? If the suction side connection is loose this will cause the pump to suck air when attempting to prime and either significantly impair it from fully priming or prevent it from priming at all.
  13. Repeat step 10 and turn on the pump again but this time make sure you have a running garden hose present beforehand. Run the garden hose water over the suction side connection on the pump pot and see if you can improve the water flow into the pump. Also try running the garden hose over any open suction side valves to see if you can discover that they are sucking in air. If the pump sucks in more water (meaning the garden hose significantly improves the priming capacity) then you have probably discovered a suction side leak that is preventing the pump from fully priming or priming at all.

These steps will resolve by far most pump priming issues. If these steps do not yield success then call a pool professional for a diagnosis of your system.

Best wishes with successfully priming your pump!


More Pool Maintenance Nuggets of Wisdom »

Build the Pool of Your Dreams

The convenience of having your own beautiful glimmering oasis of refreshing pool water just a few steps from your back door is truly a splendid thing. A pool can be everything from a source of evening relaxation, to a morning fitness spot, to a social status symbol. Your home swimming pool can be anything you want it to be.

Blue Science will work hand in hand with you to design a one-of-a-kind dream pool which perfectly complements your backyard environment. Give us a call today.

What Customer are Saying About our Dallas Pool Care

"Nate has been overseeing the weekly service of our pool since we first built it and he has helped us work through all the 1st year issues and questions that come with being first time pool owners." ~  Jul 18
»Pool Cleaning in Rockwall 5/5 ★★★★★
"Absolutely FANTASTIC service and results! My pool had very deep stains and streaking. Blue Science performed an acid wash and the results were AMAZING! They did everything exactly as discussed with me PLUS an extra services! Mike, Kelsey and Nick were all so helpful and definitely went the extra mile to make sure I was happy with their service. I also use them for weekly pool cleaning and I can't say enough about how professional and yet personable they are. Thanks everyone at BLUE SCIENCE!" ~  Jul 3
»Pool Cleaning in Corinth 5/5 ★★★★★
"I had several maintenance technicians but they were for 98% all very good and nice and polite. But I must give a special mention to Jeff Smith for his professionalism, efficiency and skills." ~  Jun 28
»Pool Cleaning in Flower Mound 5/5 ★★★★★
"I had a great experience with this company from beginning to end. Matt came out to meet, greet and measure. I told him exactly what I wanted. He didn't try to upsell or oversell. He was honest in telling me what I needed and what I didn't need. Jesse, my field superintendent called me everyday to keep me informed of the day's work and progress. For the little bit of renovating I did, my pool looks brand new! In keeping with the "Blue Science" integrity, I hired them for my weekly pool service as well! Thanks Guys!" ~  May 14
»Pool Remodeling in Coppell 5/5 ★★★★★
"I used your website to troubleshoot why my pump would not prime, your garden hose tip did the trick! I wish I lived in Texas, I would definitely use your company! Thank you so much!!" ~  May 13
»Pool Leak Detection in Addison 5/5 ★★★★★
Review Our Services

Dallas Pool Brands We Know & Use

   
When providing pool repairs and equipment installations in Dallas, we use only supplies and parts from top pool companies.