How to Prime a Pool Pump | Tips and Tricks




It’s a perfect summer day, and you’re eager to dive into your shimmering pool, only to find that you have air in pool pump – an airlock, a common yet often overlooked issue.

Once you learn the simple steps of how to get air out of pool pump, you’ll be a pool maintenance whiz in no time.

In this article, we’ll lift the veil on the two primary hideouts of trapped air: your pool pump strainer and filter housing. We will explore easy-to-follow tips to banish air locks by priming your pump and keep your pool crystal-clear all summer long.

So, let’s dive right in and unlock the secrets to a flawless pool pump performance!

how to get air out of pool pump
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How to remove air from pool pump

Bleeding air from a pool pump.
If your pump strainer housing is full of air, and your pool pump is making a noise due to air in the system, it may be that after a few minutes of running the pump the air disappears. If this doesn’t happen and water doesn’t start to flow through it so the strainer housing gets filled then you may have to help it.
So to get air out of the pool pump try this:

Shut off the pump & close skimmer valves

Shut off the pump and then close your skimmer lines using the inline valves. If you have more than one skimmer you may have individual feeds into the pump or perhaps just one which controls both.

Open bottom drain valve

Fully open the bottom main drain valve (the line that comes from the drain at the bottom of your pool)

Start the pump and open skimmer valves

Start the pump and let it run for 30 seconds. Then slowly open one of the skimmer valves a little bit at a time. Water should start to slowly fill the strainer and the pump will go quieter.

Open filter bleed valve

At this point you can try to remove any air that may be trapped in the filter by using the air relief valve positioned on or by the filter (see the section below).

Still no water?

Once the skimmer valves are fully open you should have plenty of water going through the system and the air should be gone.

Using a hose in the skimmer

I had problems, after changing the sand in my filter, with removing the air that was trapped in my pool pump and used this method. It cleared the air in less than a minute.

If the pool pump still won’t prime then try this:

  1. With the pump running, take a hose pipe and push the end into the hole at the bottom of the skimmer that goes to the pump (the one furthest away from the pool if you have two holes at the bottom of your skimmer).
  2. Now turn on the hose with a strong flow. This should push water into the pump and take any air or other blockages with it).
  3. Once there is water in the strainer basket and you can hear the sound change in the pump, showing that it is now pumping water rather than air, switch off the hose and remove it.

How to get air out of sand filter

air bleeder valve pool filter
air relief valve on the pool filter

Step 1. How to get the air out of a sand filter could not be easier than using the air relief valve on the pool filter.

Step 2. Where is the air bleed valve on a pool filter? Look for your air bleed valve which you will probably find on top of the pool filter housing, often just below or behind your pressure gauge. With air in the system, the pressure gauge is unlikely to be showing a reading.

Step 3. With the pump running on the filter setting, slowly open the valve. If air is present in the filter housing you will hear air hissing out from the valve.

Step 4. Continue with the valve open until water starts to come out of the valve.

Step 5. Close the air relief valve on the pool filter and that is the filter bled!

How do you know if there is air in the system?

You may be able to see air by looking into the clear lid of your pool pump strainer housing. If you can see water flowing from the inlet into the pool pump basket then it is not full of water (obviously).

How to get air out of pool pump basket? In most cases this air will work its way out as the pump runs.

If you cannot see any water running then it is either completely full of water, so no air, or is completely full of air. If water is being pumped back into the pool then it cannot be full of air so it must be full of water!

Your pool pump may be making a different noise (usually louder) than it does normally. It will do this when it is trying to pump air or just a small amount of water and air.

There may be little or no water coming out of your pool outlets or waterfall if you have one even though the pump is operating on the filter or recirculate settings. This is probably going to be caused by an air lock in the system somewhere.

If you are starting to vacuum you may have little or no suction. This can be a sign that you have air in the system. It may clear on its own after a minute or two.

Priming a pool pump when opening a pool

If you have just filled your pool after emptying it for the winter then you may need to prime the pump and filtration system to purge it of air that will inevitably be there.

This is a pretty straightforward operation and I do it this way:

  1. With the pump off, move the multiport valve handle to the recirculate setting so water doesn’t flow through the filter but goes straight back to the pool instead.
  2. Take off the pump lid to the pool pump strainer housing.
  3. Using a garden hose, start filling the system through the strainer and let it run for a few minutes. This will start to fill the system through to the skimmers, assuming your skimmer valve is open. If you can, push the end of the hose into the opening where water comes into the strainer from the skimmer. This would be the higher one of the two openings – the lower one goes to the pump. You may see air coming out of the skimmers which is good.
  4. Put the pump lid of the strainer back on firmly.
  5. Switch the pump on and run until you can see no air in the system.
  6. Shut off the pump and put the multiport valve to the filter setting before switching the pump back on.

Pool Care Handbook and Video Course

When I bought my house with a swimming pool, I knew absolutely nothing about pool care. I just winged it for a while, making many mistakes along the way.

Fortunately, I was recommended Swim University’s Pool Care Handbook and Video Course. I bought it and it was an absolute game-changer.

It was the best money I spent that year. I learned everything from basic cleaning to advanced troubleshooting. Swim University offers a no-quibble refund policy too so what do you have to lose?

Why does my pool filter keep getting air in it?

The most likely reason for having air in the pool pump or filter will be that you have just cleaned the pool and the action of stopping and starting the pump to backwash and rinse etc has allowed some air into the system.

  • You often have it when you first start to vacuum too. You can help to eliminate this by making sure you remove the air from your vacuum hose before you start.
  • If the water level in your pool is low so it is not covering the bottom of the skimmer then this will allow air into the system and is an easy fix of course by just topping up the water level with a hose.
  • If you have emptied your pool for the winter then you are likely to have air in much of the system. You may need to prime the pump to get it to start pulling water and any other air through the system.
  • You may have an air leak in the pump lid of the pump strainer housing which could be letting in air. This could either be that you have not closed it properly when you removed it to empty leaves and other debris from the strainer basket or the o-ring in the lid may be faulty and need replacing.

The least likely (fortunately) is that air is getting in somewhere else in the system prior to it entering the pump.

Check that any pipe fittings are not loose and letting air in. If you can’t find any then it may be a crack or similar in the pipework between the skimmer and the pump. If this is the case you are probably also losing water from the pool.

Unfortunately, I had this problem which resulted in lots of digging and the pipework being replaced (see below).

how to release pressure from pool filter

Why is my skimmer not skimming?

Do you remove the skimmer basket when vacuuming a pool?

How to empty a pool pump basket without getting an air lock

Is air in a pool pump bad?

Yes. Having air in your pump is bad for two reasons. It will mean the pool filtration system cannot run at peak efficiency and also running your pool pump “dry” for any length of time will lead to it failing.

Why is my pool pump pressure high?

The most common reason why your filter pressure gauge will be showing a higher pressure than normal is that the filter is clogged with debris so back pressure is building up. The way to fix this is to backwash.

Should my pool pump basket be full of water?

Your pump basket should be full of pool water. If there is a small amount of air trapped at the top that won’t be a problem and this should disappear after a while when the pump is running. If air bubbles persist then it may be that air is getting into your system through the o ring or from somewhere else and will need investigating.

My top 3 pool cleaning tools

These are the pool cleaning tools I have found the most useful since I have had my pool.

Step and corner vacuum brush

This is a really useful tool for getting into the areas that a standard vacuum head simply cannot reach. Aquatix Pro Pool Step & Corner Vacuum Brush

Leaf rake net

If, like me, you get plenty of leaves at the bottom of your pool then a good leaf rake/net is a must. The Stargoods Pool Skimmer Net gets under the leaves easily.

Robotic pool cleaner

These are quite expensive and it was a number of years before I bit the bullet and bought one. I have never regretted it. The Dolphin Nautilus CC Plus is the most recommended pool cleaning robot on all of the pool forums. It not only cleans the bottom of the pool but also the sides and the waterline.