hot tub wiring

Hot tubs and spas offer wonderful ways to have fun or relax, though when it comes to hot tub wiring and the often confusing installation processes, new hot tub users often need help.

Most hot tubs and full-sized spas require hard-wiring with a ground fault circuit interrupter (GFCI) amp circuit that runs with 220v-240v and 50 or 60 amp.

In this guide, we will show you the ins and outs of wiring a hot tub so that you can get to enjoy yourself as soon as possible.

Disclaimer: If you do not feel qualified or confident when wiring your hot tub, we recommend hiring a licensed electrician. To contact top rated licensed electricians in your local area that can install your hot tub, fill out the form below. Select “Hot Tubs/Jacuzzi/Spa – Install” from the drop down. You will instantly be matched with several professionals to choose from. 

Electrical work can be extremely dangerous, even more so when the work is near water. Always make sure to carefully follow your hot tub owner’s manual and go over any associated electrical component manuals before attempting to wire your hot tub.

Important Thing To Note About Wiring a Hot Tub

The first thing you will need to know is the voltage potential of your home. To get an idea of the current you are supplied with, you will need to know your home’s voltage potential. the precise current amount will be slightly higher or lower than your home’s potential voltage supply.

When looking at various hot tub electrical requirements, knowing this information will come n handy. for example, you could decide to purchase a plug-n-play hot tub with 120v power requirements that you could plug directly into any wall outlet or purchase a traditional 240v hot tub that you will need to wire to your home’s central circuit breaker.

If you’ve been searching for hot tubs online, you’ve probably come across the two main hot tub types.

Plug-n-Play Vs. Wired Hot Tubs

Plug and play hot tubs do not require any special wiring, which is why they are often so popular for new spa buyers.

The reason they are called “plug-n-play” spas is that you can plug them directly into a 120v wall outlet to start it up.

Traditional wired hot tubs will either have 220v, 230v, or 240v power requirements, meaning you will have to directly connect them to your home’s breaker.

You won’t have the same mobility with a traditional spa compared to a plug-n-play spa for this reason.

However, there are a few advantages to traditional wiring. For starters, the direct connection to the circuit breaker gives wired spas more power and heat. Compared to plug-n-play spas, traditional wired spas can obtain a heat rating of more than 300%.

Traditional wiring allows your spa to heat up much faster, making it better for colder climates, as well as for those who simply don’t like waiting around.

How To Wire A Hot Tub

Hot tub wiring should be performed by a professional licensed electrician. It is important to recognize the dangers of working with electricity and water, as one wrong move could lead to injury or death.

Plus, licensed electricians often understand the greater installation requirements, as well as building codes, which can change how you can install a hot tub. The average person probably won’t know the various requirements that stem from specific jurisdictions.

Prior to moving ahead with the hot tub installation process, we recommend getting in contact with the enforcement agency in your local area to retrieve the necessary codes.

Prior to diving into the hot tub installation steps, let’s talk a bit about the various supplies and components found within the spa system that you will need to focus on.

Circuit Breaker

Your breaker is going to be the first thing in your system that will differentiate a wired spa and a plug-n-play spa. A wired spa will require a separate breaker on your breaker panel that has dedicated power running to the spa.

It is important to match your service panel with the appropriate-sized breaker panel. You will most likely be able to find this information on your hot tub wiring diagram.

However, when determining the breaker necessary for your hot tub, it is best to speak with a professional electrician.

Service Panel

It is important to have a place in your home’s service panel to connect and install your spa’s 220v breaker. Your breaker panel must have the proper requirements to send and support the current necessary for the spa to run.

If you don’t have enough current to support your hot tub’s functionality, it is important to consult with an electrician.

GFCI Shut-Off Box

The National Electrical Code requires that every wired spa has a ground fault circuit interrupt (GFCI). You can think of a GFCI as an emergency disconnect device, which helps to cut the power of your spa from the original source.

It is also important to install a fail-safe power shut-off for any time that your GCFI is not working. It is a mandatory requirement for spa installations that a GFCI shut-off box is installed anywhere from five to six feet away from a spa.

Additional Power Outlet

Another mandatory requirement from the National Electrical Code is the provision of an extra power outlet. The installation of the power outlet must be 10 feet to 20 feet away from the spa.


To find the right wire size for your spa, you must first consider the total current that your spa needs. Smaller wires are more prone to electrical fires. Plus, it increases the damage risk for your pumps and heating elements.

It should also be noted that aluminum wire should be avoided at all costs. The recommended wire for a traditional spa is 6 AWG copper wire.


When it comes to installing a hot tub outdoors, the majority of localities will require and spa wiring to pass through a conduit pipe. Many regions allow the use of plastic or metal conduit pipes, though it is important to consult with your local enforcement agency for electrical codes.

Your local enforcement agency will also provide you with how far down you must bury your plastic or metal conduit, as the rules can change based on the agency. Many conduit trenches can be up to 18 inches in the ground.

Wiring a GFCI

Turn Your Power Supply Off

Before you begin with any form of installation, you must disconnect your power source.

Install a Service Panel

Make sure that your home has enough space for an additional load before installing your service panel. A service panel will help you avoid false tripping.

False tripping comes along with the direct wiring of a spa to a 2-pole GFCI breaker. Explore the requirements of your -panel and follow the necessary procedures for installing it on a nearby wall. Make sure that the spa panel sits no more than 5 feet from the location of your spa.

Dig A Space For The Conduit

You will want to run the wiring through a conduit. To make room for this conduit, you will want to use a shovel to dig a trench where you will lay the wiring that will run to your spa panel.

It is very important to consult the local enforcement agency for local codes on conduit depth. The last thing you want to do is hit a utility cable during your digging process.

Pull the Wire Through The Conduit

Drill a hole through your wall to run the conduit. To channel it out of your house, you should make sure that it is close to the main breaker panel. Cover your main breaker panel, spa panel, and trench with conduit covering.

If your wire is longer than six feet, you will want to use liquid-tight flexible metal or a non-metallic conduit. If your gr0und wire is longer than six feet, you will want to use a non-metallic conduit for your direct burial.

Using an LB fitting on the hole in your wall, connect your indoor conduit and outdoor conduit. You can use fish tape to pull your wire into your spa panel from the fitting.

You can use sweep fittings if you want to make gentle curves without a perfect 90-degree angle. Using copper wires with thermoplastic nylon, pull your wiring through.

Pro Tip: It is often helpful to have someone else around who can help push or pull the wire through.

Connecting Your Wire

Connecting your wire can be fairly complex. To get the optimal results, follow these steps in order:

  • Connect the black and red load wires to your circuit breaker box
  • Connect the green ground wire and white neutral ground wire to your service panel’s neutral bar.
  • Run your four wires to your GFCI breaker box through a conduit
  • Connect your black load wire to Line-in 1 on your GFCI and your red load wire to your GFCI’s Line-in 2.
  • Connect your white neutral cable to your GFCI breaker box’s neutral bar and the green ground wire to the bus bar.
  • Connect your white pigtail to the neutral bar in your GFCI. If you have a 240v spa control system, run the black and red wires from Load-out 1 and Load-out 2 respectively to the grounding bus bar. You must also run the green ground wire to the bus bar as well.

Check Your Wire Work

Make sure that your copper wire is of the appropriate size for your particular connections. To find out the right wire size to use within your home, it is best to contact your local enforcement agency to retrieve code requirements.

There are spas out there that allow users to route wire within the cabinet of the spa, as running wire beneath a spa isn’t permitted. Local codes also often state that spas may not be placed directly under communication or overhead power lines.

Hit the Power Switch

Turn your hot tub power supply on, as well as the new breaker.

Are Direct-Wired Spa Models Worth It?

There are a few reasons that you might want to go with a traditional direct-wire hot tub rather than a 120v plug-n-play hot tub.

In the case that you live in a place that goes through extreme temperature changes or cold temperatures in general, having a directly-connected spa will allow your heater to run optimally. Plug-n-play hot tub models often have a hard time keeping up with extreme temperatures due to the lack of power.

Another reason that a directly-wired hot tub might be better for you is if you are someone who likes to heat and cool your hot tub fairly frequently. Wired hot tub models can heat up far faster than plug-n-play models.

For example, the CoolZone hot tub cooling system, which comes from the Hot Spring spa manufacturer, can heat a spa up in just a few hours.

Enjoying Your Hot Tub

Prior to using your hot tub, we highly recommend getting in touch with an inspector who can come and inspect the wiring connections in your home. Once your connections have passed a professional inspection, you can begin filling your spa with water and preparing it for use.

As we said before, spa installation requires knowledge and familiarity with electrical equipment and local codes. If you do not have any experience with spa installation or electrical wiring, you should consider hiring an electrician.

You can find prices for local licensed electricians with a simple Google search. The majority of electricians charge anywhere from $50 to $100 per hour, meaning you will likely spend around $300 for an electrician to come visit your home on average.

Of course, the most complicated part of owning a hot tub is the installation process. Once you understand the ins and outs of hot tub wiring, you will be able to enjoy the many benefits of owning a spa.

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *