Have you ever turned on your hot tub and the jets refused to, well, jet? There’s nothing coming out. No water, no air, no nuthin’. A hot tub without working jets is basically a very expensive bathtub, so you’ll no doubt want to fix this right away. But just what the heck is going on?
Sounds like a hot tub air lock. And no, we’re not talking about the air lock you’d find on a spaceship. You’ve got air in the plumbing lines. But that’s OK, because we’ve got a line on how to fix it so you can get back to soaking without all the swearing.
To understand why your spa isn’t working, you first need to understand how it’s supposed to work. Very simply:
If you turn on the pump, but little to no water comes out of the jets, you have a hot tub air lock.
The most likely time for this to happen is when you drain and clean your hot tub every quarter. You do, right? Right.
When you drain the spa, water doesn’t just come out of the tub. It also drains from the pump and the plumbing lines, which power the jets.
Then you refill the tub. As the water rises and reaches the jets, theoretically, it should run into the jets and refill the lines as well. But that doesn’t always happen.
Instead, the air that has replaced the water in the pump and jet lines creates a block, preventing the water from running into the lines. It’s a power struggle between air and water, and air often wins this one.
Once the hot tub is refilled and you turn the jets on, there’s no water in the pump or the lines, so there’s no water for the jets to push into the tub. This is bad because the water isn’t circulating the way it should.
But it’s really bad because you never want to run a pump with no water in it. Pumps are made to function with water. Without it, the pump’s motor could burn up, and it’ll cost you money to either repair or replace it.
But before it even gets to that point, you can easily fix a hot tub air lock yourself. All you have to do is prime the pump.
Let’s start with the easiest of two methods. With just a few pushes of a few buttons, you can quickly fix a hot tub air lock. You won’t even need any tools for this one.
This is an easy fix, but it doesn’t always work. If, after trying this three or four times, the air lock still isn’t resolved, stop the procedure to avoid damaging the pump, and try the next fix.
This is a 2-speed pump that takes 240 volts and pumps out 4 horsepower.
If burping the spa didn’t work, you can use the pump’s bleeder valve to expel the air and relieve the hot tub air lock.
You may need a couple of tools for this one:
If you’re still having problems after priming the pump, you can try a few other hot tub air lock remedies.
That oughta do it! But it still might not. In that case …
Soak your hot tub filters in this deep-cleaning solution, rinse with water, and your filters will look brand new in 24 hours!
So this is actually the easiest method, but it’s also the most expensive one. But if nothing you’ve tried has fixed the hot tub air lock, or you’re just not comfortable doing it yourself, don’t hesitate to call in a pro.
We wish we could tell you how to keep a hot tub air lock from happening in the first place. But it’s just physics, and there’s no way around that. It will definitely happen to your spa at one time or another, or many times.
But now you know how to handle it so it won’t be so frustrating when it does occur. And as for the other possible water flow issues, just keep your hot tub clean and well maintained, and those things you should be able to avoid.
Happy Soaking!
Matt is the founder of Swim University. He's been in the pool industry since 1993. His mission is to make pool care easy for everyone. Each year, he continues to help more people with water chemistry, cleaning, and troubleshooting.
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