Help! There’s an Air Lock in my Hot Tub!

Hot Tub Air Lock

Have you ever tried to use your hot tub and the jets have stopped working? Nothing is coming out. There’s nothing there, no water, air or anything. A hot tub with broken jets is essentially a luxury bathtub, so you’ll want to fix it as soon as possible. But exactly what’s going on?

Many people don’t know that hot tubs can sometimes develop air locks. This is a problem because it will prevent water from circulating and your hot tub won’t work properly.

Not only will the jets not work, the chances are that the heater will not work either. If there is no flow or no consistent flow, then your pressure sensors or switches will not activate properly.

You will get an error message on the control panel like PS1, PS2, PS Low, (pressure switch problems) No Flow, Air in System and many more messages which mean the same thing. There is air in your system!

It’s important to learn how to remove an air lock before it becomes a bigger issue! In this blog post, we’ll give you the scoop on how to remove an air lock in your hot tub so that you can enjoy soaking once again!

How do I know if I have an Air Lock in my Hot Tub?

It is quite easy to tell if you have an air lock in your hot tub.

If you turn on your pump and there is simply nothing coming out of the jets. If you turn on your pump and only a couple of the jets are working. If you turn on your pump and the jets are working but there is no power in them. Then the chances are that you have an air lock in your hot tub.

We’ve seen in a previous post how the pumps may not be running properly and this can be a capacitor problem, so it is important to check that the pump is running correctly. If it is and there is nothing coming out of the jets, then it is an air lock. If the pump is humming and not running properly, then check out this post which might help.

What Causes an Air Lock in a Hot Tub?

Air locks can happen for several reasons:

There is a crack in the pump. The pipes and jets are dirty and clogged with debris. Air has entered the system and become trapped during filling. This is the most common cause by the way!

How Do I Fix an Air Lock in a Hot Tub?

Luckily for you, we know exactly how to remove an air lock from your hot tub!

“Burp” your Hot Tub!

This is a pretty straight forward method. It is kind of like rubbing the back gently on a baby to make it burp after feeding. In our case, we are trying to tease the air out of the tub!

  1. If your spa has a control panel, look for the priming mode on it. If yours doesn’t, that’s OK; you can still accomplish the same thing.
  2. Turn the jets on low for 15 to 20 seconds.
  3. Switch the jets to high for another 15 to 20 seconds.
  4. Continue repeating this procedure until the jets are running freely without any irregular flow or bubbles.

Release Air Directly from your Tub.

There are a number of places that you can release air directly from your Hot Tub.

Firstly, on the face of your pump itself there is usually a air bleed screw. There may even be two depending on the model of pump you have.

Once you have located this screws you are going to want to close the gate valve on the discharge side of the pump. This is usually the one that that you will find after your Spa Pack.

Then, you are going to open the bleed screws on the front of the pump. Don’t worry if you have some water come out after the hissing, this is totally normal and it is actually a good sign.

Tighten the valve up, open the gate valve and try the pump again.

If this does not work, then the next step is to loosen the top of the filter. Make sure the pumps are not running and then remove the cover to the filter. Some filters actually have their own bleed screw at the top of the filter that you can use to let air out. The filter is a popular place for trapped air to sit.

A little more extreme measure is to loose the union nut on the top of the pump. Again, you are going to want to close the gate valve on the way back your jets, so the one after the spa pack.

Slowly loosen the nut again you should hear a hissing sound. When this stops and water begins to flow out of the union, lock it off again.

Once secure, open the gate valve and try the pump once more.


There can be quite a lot of air trapped sometimes in your tub so dont give up! persistence is the key here as you will be able to release it eventually and it may take several attempts to do so.

If all else fails?

What is the last resort when all else fails? Simple. Drain the tub and start again. When the tub is pretty much empty, give the jets a run for 2-5 seconds. No more than this as pumps are not designed to be run without water and a load on them.

Likewise, with the blower, give that a little bast for 2-5 seconds just to try and purge any water and air that is sitting in the pipes.

When you fill up the tub, you should be filling through the skimmer rather than just pouring the water from the hosepipe into the centre of the tub. This can help reduce air locks.

Can I Help You?

If I can help you in any way I would love to hear from you. You can get in touch using the form below.

Thanks - Andi


Hi, Andi here. I own and also write all of the articles and info pages on the site. Some years back now, I built my own hot tub but struggled to find the information I needed. So, once my tub was complete, I started this website to help others in their own pursuit of hot tub and plunge pools DIY building information.

Today, I've helped over 700 DIY customers just like you all over the world build hot tubs and pools. Have a good look around the site, there are lots of resources here. Please do get in touch if I can help you. - Cheers, Andi

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