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How Can I Tell if My Hot Tub is Leaking? (Step by step fixes)

By: Author Jeff Campbell

Posted on  - Last updated:

Categories Hot Tub Repair

Throughout the years of owning a hot tub, you will run into issues. Big hot tub leaks are rare but pretty obvious. But sometimes hot tub owners just notice the water level dropping. If that’s the case, it’s natural to ask how can I tell if my hot tub is leaking?

Hot tubs do lose an inch or two of water weekly depending on the water temperature and air temperature. However, you can tell your hot tub is leaking when you notice more than a 2-inch drop over 7 days, or if you see water pooling around the base of the hot tub, especially when the jets are on.

But that’s just a quick glimpse into hot tub leaks. Where they happen, how they happen, and how easy they are to fix varies pretty widely!

It can be frustrating looking for leaks in your hot tub because they can be small.

You may also be thinking that fixing the leak will require a hired professional. While in some cases that may be true, you may be able to fix a leak depending on your level of expertise, especially if it is a simple and common leak.

Keep on reading to find out how to tell if your hot tub is leaking, and what to do about it.

Ready to Spend Less Time On Maintenance and More Time Enjoying Your Hot Tub?

Let’s face it. Balancing the water, cleaning filters, dealing with rashes, and trying to figure out which chemicals to buy and add can make you feel more like a chemist than someone who just wants to relax after a long hard day!

That’s exactly why The Hot Tub Handbook and Video Course is so valuable!

This is from Matt over at Swim University and he developed it for people looking to save money, time, and frustration. His tips on chemicals can save you $100/year just by making sure you buy only what you need.

So if you’re ready to stop being confused or frustrated with your hot tub and start spending more time in it, check out The Hot Tub Handbook and Video Course.

Just click that link to learn more on their website.

hot tub cheat sheet banner Hot Tub Owner HQ

Where do hot tubs usually leak?

Hot tubs most often leak at the pump and the union fittings on either side of the heater tube. But by removing the panels on the side of the hot tub, simply look to spot the location where water is dripping or pooling the most.

Some are easy to spot and easy to fix. Others are a royal pain. Below, we’ll review the most likely ones, how to spot them, and how to fix them.

The Pump

The most common location you will find leaks in your hot tub is the pump. Before checking your hot tub’s pump for a leak, ensure you have turned off the power. Then look under the pump for leaking water.

Other common areas where you can find leaks are the union fittings, heater, valves, connections, and shell. If you’ve checked the pump and it isn’t the culprit, move on to these compartments of your hot tub.

In my experience, the most likely culprit are those rubber gaskets used where the pipes connect to and from the pump. Luckily, that’s just a matter of closing off the shut-off valves, unscrewing the fittings, and replacing the gasket with a new one the exact same size.

The Heater

When checking the heater of your hot tub, you will be checking the entire heat assembly manifold for a leak.

The heat assembly manifold consists of the heater and pressure switch alongside a few other small components.  That sounds fancy, but basically, we’re talking about a long silver tube usually on the underside of your control box.

On one side (typically the left) it will connect to the pump (which pumps water into the heater). Then it comes out the other side and goes back into the hot tub.

Those gaskets I mentioned in the section above are often a common culprit here too.

The Union Fittings

The union fittings are found around both the pump and heater. These can become easily loosened over time. Always tighten the union fittings by hand. Never tighten the union fittings with a wrench, as this can cause damage.

Typically these are in 2 pieces. They screw into each other and then are threaded to screw onto the opposite fitting.

There’s a rubber gasket in each one, and the constant hot water can cause them to wear out or break over time. They almost always leak when that happens. Luckily, that’s an easy and inexpensive fix.

Valves

Inspect every valve on your hot tub. There are several different style valves that may be on a hot tub.

For example, knife style valves have a gasket between both halves that are bolted together. As with many of the other fittings, the gasket is a common cause of leaking. Check carefully and ensure that they are not leaking.

Connections

Check all of your hot tub’s pipes and jets.

In most cases, all you need to do is tighten or reseal the connections to stop the leak. If your jet is leaking, it is most likely caused by a failed gasket. This will need to be replaced, so check with your hot tub manufacturer for what type of gasket to buy.

Hot Tub Shell

The majority of hot tub shells are made of strong fiberglass and other combined layers, making it difficult to leak.

In most cases, it is actually a problem with one of the jets or other components that attach to the shell, and not the shell itself.

If there is a crack in the shell, it’s easy to spot, but only when it’s empty. If you’ve tried all the other ways to check and inspect, then your next step is to drain it and look for a crack in the acrylic shell.

Here are the steps to fix a small crack in the acrylic shell:

  1. Drill a tiny hole at both ends of the crack.  You want the hole to be bigger than the size of the crack but only by a tiny bit. The holes will stop the crack from getting larger
  2. Use Plast-aid Acrylic Repair Kit (click to see the current price on Amazon)
  3. This comes with both a powder & a liquid. Just mix according to the instructions. Then, quickly spread into the crack and holes
  4. It’s a good idea to wear latex gloves to keep the mixture off your hands
  5. Very quickly wipe away the excess mixture from the shell. This dries fast!
  6. It dries white, so you can mix in a small amount of acrylic paint to match the color of your hot tub.
  7. Once dry, lightly sand and buff to a shine. 

What do I do if my hot tub is leaking?

If a hot tub is leaking, remove the side panels to identify the location of the leak. Leaks at the pump or heater may require replacing worn rubber gaskets, while leaks from jets encased in foam may be able to be fixed by pouring Marlig Fix-A-Leak into the water and allowing it to seal the leak.

CLICK HERE to see Marlig Fix-A-Leak on Amazon.

Of course if you need to disassemble the pump or heater, first, switch off the electricity. If the leak is major, meaning you see gushing water, once you’ve determined the source of the leak, it may be best to go ahead and drain the hot tub altogether to make the repairs easier to perform.

However, many newer hot tubs have gate valves on either side of the pump and heater. These can simply be closed to allow disassembly without draining. They have a plunger you simply push down to close.

Most hot tub leaks come from the pump, it might need a new seal or housing.

Leaks from jets, unions, and connectors might just need tightening or replacement gaskets. Minor cracks in pipes and small leaks can be treated with a sealer.

Before you commit to fixing a leak or paying to fix a leak, check to see if your hot tub is still under warranty. If it is, you’ll be able to get the leaks repaired by a professional for free.

I’ll get more into it below, but for small leaks, especially ones around jets, Marlig Fix-a-Leak works great! I’ve used it many times with great success. Just click that link to see the current price on Amazon.

It is not, however, a miracle worker. If you have worn gaskets or (especially) cracked PVC pipes, this will not work.

Ultimately, hot tubs have a lifespan and depending on how old yours is and how bad the leaks are, it could be time to consider a new one.

On average, as I detail in this recent article, portable hot tubs last about 15 years. BUT, there are some things you can do to maximize and extend that lifespan.

Just click that link to read it on my site.

hot tub cheat sheet banner Hot Tub Owner HQ

Does Fix a Leak for hot tubs work?

Marlig Fix-A-Leak will work to fix almost all leaks in a hot tub that are smaller than 1/8 inch in diameter. So it works well on leaks at jets but will not work well for a cracked PVC pipe.

CLICK HERE to see Marlig Fix-A-Leak on Amazon.

The amount you will use depends on the leak. If it’s a small or minor leak, you’ll most likely only need the 8-ounce bottle.

If the leak is more severe, then the 32-ounce bottle may be required. But honestly, I always have a quart on hand, as minor leaks crop up somewhat regularly once a tub is 5 years or older.

If this is the case, start by using 1/3 of the bottle. Normally, FIX-A-LEAK will seal holes as large as 1/8 inches in diameter.

Here is how you use Fix a Leak.

First, determine the amount of water loss over 24 hours. Do this by measuring the water level drop in that period and then select the amount of Fix A leak that is needed.

Next, fill the hot tub to the original level and mark the waterline. Then remove the filter(s), and shake the bottle of Fix a Leak well. With the pump running, slowly add the product through the skimmer or in front of any suction intake.

Finally, recirculate continuously for 6-8 hours then shut the system off. Check the water level the following day. If the water level remains the same, the leak has stopped. Allow 48 hours before resuming operation.

Amazingly, you do NOT have to drain it and refill it before using it again.

CLICK HERE to see Marlig Fix-A-Leak on Amazon.

Leaks are just one of the things hot tub owners have to deal with. In fact, there are 23 crucial things to know and questions to ask before buying your first hot tub. Curious?

Check out this recent article to find out the other 22. After all, they are things existing hot tub owners need to know too.

Just click that link to read it on my site.

How much does it cost to fix a hot tub leak?

Hot tub leak repair by professionals will range from as little as $200 to up to $1500 if it requires accessing jets encased in foam in the underside of the hot tub.

But seriously, I’ve fixed many leaks myself and never had to hire anyone.

In some cases, it may make sense to just get a new pump, blower, topside panel, or control box. After all these parts are in the hundreds of dollars. And the average homeowner with some DIY experience can easily replace those things.

For professional repairs, just be aware that there may also be a minimum charge of $150-$200 for inspection and basic maintenance.

And sometimes it’s hard to find repair companies willing to work on portable hot tubs. Many companies only work on in-ground hot tubs (because they are not only easier to work on, but they can charge more).

How do you fix a broken hot tub pipe?

To fix a broken pipe, first, disconnect the electricity.

If the leaking pipe has a shut-off valve (called a gate valve) on either side of it, close those off. Otherwise, you’ll need to drain the hot tub.

Sometimes you get lucky and the leaking pipe is short and you can just unscrew it from the fittings and replace it. If not, though, be prepared to cut and glue.

Use a hacksaw to cut out the leaking portion of pipe and fittings.

Then use PVC couplings to join the replacement pipe and fittings to the solid existing pipe. Wearing disposable gloves and allowing for adequate ventilation, apply a thin coat of PVC primer to the outside ends of the pipes and to the inside hubs of the fittings.

Next, apply a thicker coat of PVC cement over the primer.

Push the pipe and fittings together, hold them in place for 30 seconds or so, and release. Open the gate valves if you closed them, but wait at least two hours for the glue to dry before filling the spa.

Once you start filling it back up (if you had to drain it), turn the power back on once the water level is half-full. Once the water level is above the jets, turn on the jets and other water features. This will speed up the heating of your hot tub.

Leave the cover on while you do this. That also helps keep the heat in the water.

Final Thoughts

The most common area a hot tub leaks at is the pump. But other areas it can happen include the union fittings, heater, valves, connections, and shell.

If you find that your hot tub is leaking, switch off the electricity and locate the leak. Check to see if your hot tub is still under warranty before you commit to fixing or paying to fix a leak. You can also try using Fix a Leak. It’s an easy to use sealant capable of fixing many hot tub leaks.

Fixing a hot tub leak can become expensive if it’s a major issue, costing you anywhere from $200- $1,000 to repair it. It may even cost $1,500 if it is your hot tubs cabinet that is leaking.

Didn’t quite find the leak solution you wanted? 

I have another article that goes more in-depth into certain types of leaks, including one of the most common. So make sure and check that out for some additional solutions.

Just click that link to read it on my site.

hot tub cheat sheet banner Hot Tub Owner HQ

Ready to Spend Less Time On Maintenance and More Time Enjoying Your Hot Tub?

Let’s face it. Balancing the water, cleaning filters, dealing with rashes, and trying to figure out which chemicals to buy and add can make you feel more like a chemist than someone who just wants to relax after a long hard day!

That’s exactly why The Hot Tub Handbook and Video Course is so valuable!

This is from Matt over at Swim University and he developed it for people looking to save money, time, and frustration. His tips on chemicals can save you $100/year just by making sure you buy only what you need.

So if you’re ready to stop being confused or frustrated with your hot tub and start spending more time in it, check out The Hot Tub Handbook and Video Course.

Just click that link to learn more on their website.

As an Amazon Associate, I may earn a small commission from qualifying purchases if you click on Amazon from my site and choose to make a purchase. You can read my complete affiliate disclosure for more details.

Jeff Campbell
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