How to Find a Leak in a Hot Tub

If you are a proud owner of a hot tub, the last thing you want is to find that your hot tub has a leak and to have to deal with it. A hot tub has many parts, such as the shell, jets, pipes, valves, etc., any of which may develop a leak anytime.

Thankfully, hot tub leaks are quite easy to deal with if you know where the leak is and what to do if you detect a leak.

I’ll discuss how to find a leak in a hot tub. Then look at some of the most common causes of leaks in hot tubs and how you can fix them.

how to find a leak in a hot tub

Steps to Detect a Hot Tub Leak

Firstly, turn off the power and open the compartment and check for pooling of water or any damp spots, which are signs of a leak.

An easy method you can use to determine where the leak is by coloring the water using food coloring or dye and wherever the water appears will indicate the area of the leak.

Alternatively, you can fill the hot tub and allow the water to drop. When the water stops draining, check the parts above the water level for leaks. This will allow you to identify where the leak is.

While these methods may work for large leaks, it may not be easy to identify when the leak is not significant and you will need to inspect the various parts of the hot tub individually to determine the exact location and cause of the leak to fix it.

Ways to Fix a Hot Tub Leak

Fixing hot tub leaks is quite easy if you know where to look for them. The key is to locate the source of the leak. Leaks usually occur commonly in areas such as the:


This is the most common area where a leak can arise. Examine the pump to check for any moisture. Leaking pumps can be caused because of the shaft seal, volute or unions.

A leak in the seal usually causes water spots under the pump or you will notice rust on the motor. If there is a problem with the shaft seal, you can simply replace it to fix the leak.

If there is a problem with the volute that houses the impeller, then this may have to be replaced. Finally, if the problem lies with the union fittings, i.e., the 3-part connectors you can simply tighten it or you may have to adjust the O-ring.

If this doesn’t sort the leak, then the union fittings may have to be replaced. If the leak persists, then you may have to replace the entire pump.


The leak could be in the heater of the hot tub. The heater consists of the heater, pressure switch and other parts, any of which could be leaking. Typically, if the heater is leaking, then you will notice rust on the heater tube.

While you may be able to replace the individual component that’s leaking, it is more likely that the entire heater may have to be replaced.

Connections and Unions

The unions in the hot tub tend to become loose because of the changes in water temperature and vibrations. You can simply stop the leak by tightening the unions by hand. If the leakage continues, then try replacing the O-ring, union assembly or the gasket.

An important thing to keep in mind is that the plumbing components must be tightened only by hand because they are made of plastic and can break if you make use of tools.

Plumbing components that are glued are difficult to seal and you may have to cut the part to change them.

Jets and Manifolds

Jets usually have flexible gaskets, which are sealed against the hot tub shell. Over time, the hot water in the tub breaks down the gaskets and causes leaks. You will need to remove the jet from the hot tub to fix the gasket leak.

Before you install the new gasket, make sure that the hot tub shell, as well as the jet, are clean.

Then, apply a sealant to either side of the new gasket before tightening the gasket to the jet. This helps to create a better seal. When the water freezes inside the plumbing, then the jet manifold may get damaged and spring a leak.

You can fix the smaller cracks using Plast-Aid or Spa Bond; however, if the jet manifold is beyond repair, then you will have to replace it.

By cutting the manifold out and any elbows that are attached to it. Glue all the components into position after replacing them.


A hot tub has many valves and if any of them have developed a leak, they must be repaired or replaced. Essentially, there are 3 types of valves in a hot tub air control valves, diverter valves and shutoff valves.

Typically, shutoff valves and diverter valves, which control the water flow tend to develop leaks compared to air control valves.

You can replace the shutoff valves if they are leaking by just cutting out the leaking valves and replacing them with new ones.

Usually, diverter valves start leaking when the O-rings dry or wear out. Greasing the O-rings and other moving surfaces in the valve can help to keep these valves leak-free.

Hot Tub Shell

Typically, the shell of the hot tub is made of sturdy fiberglass or acrylic, which is combined with other layers. Usually, when there is a leak, it is not caused by the shell of the hot tub itself, but by a jet, a pipe or some other component that is attached to the shell.

If the shell of the hot tub has a crack, it is usually on the surface and you can drill a tiny hole on both ends of the crack to prevent it from spreading. You can then apply Plast-Aid or a Spa Bond patch after cleaning the area around the crack.

The Final Word

So, if you’re a hot tub owner, then it is extremely important to maintain your hot tub and keep a watch for any leaks regularly. Fixing minor leaks is very easy and also makes repair easier.

However, if you’re unable to fix the leak on your own, then it’s a good idea to call in professionals to repair the problem before it worsens and causes serious irreparable damage to your hot tub.

michael keenan author

Author - Michael Keenan

I'm Michael Keenan the owner and creator of the Outdoor Care Guide. I'm a trained horticulturist with over 30 years experience in pool care, plant care and landscape care! Seemed like a good idea to share - I think I can make your life easier and save you some time and money!