How to Properly Winterize Your Hot Tub

Residential hot tub located inside a wooden gazebo

Temperatures are dropping, and that means it’s time to start preparing to winterize your hot tub. When you close your hot tub for the winter, it’s easy for it to turn into an “out of sight, out of mind” situation. Winterization prepares your spa to resist the damaging effects of freezing temperatures, keep out the debris blown around by howling winter winds, and ensure unsupervised access is prevented to keep your friends, family, and pets safer during holiday festivities. As your Northern California pool safety pros, we’re going to help you get the job done right so your spa is ready to go when spring rolls around and warmer temperatures return.

But It’s a HOT Tub…

When looking for instructions to winterize your hot tub, you probably came across conflicting information about whether or not winterization was even needed. The fact is that it may not be depending on your hot tub and specific situation, but it’s still a good idea for added peace of mind and damage prevention if you aren’t planning on using it regularly over the winter. Modern, energy-efficient hot tubs are designed to use minimal power to heat and circulate the water, which should prevent freezing…theoretically. 

In the above scenario, a power outage can easily leave you with a tub full of rapidly cooling water and bursting lines. Even without a power outage, if you don’t close your spa for the winter, you’ll also need to maintain its chemistry and cleaning along with the heat and circulation to prevent contamination of the water or giving biological infestations, like bacteria or algae, a chance to find a foothold in the harder to clean lines and mechanisms that keep your hot tub functional. This extra time and attention (in uncomfortably chilly conditions) can not only make owning a spa less enjoyable but also erase the cost savings of your energy-efficient unit. The safest and often cheapest and lowest hassle choice is to winterize your hot tub so you have the peace of mind of knowing it’s protected and you’re free to stay warm inside your home.

The Purpose of Winterization

The biggest danger to your spa when temperatures dip into freeze territory is the water inside it. Water expands as it freezes. The same pressures that can burst copper or iron piping in home plumbing can easily burst plastic, vinyl, and PVC fittings inside your spa and the equipment that heat, filter, and circulate water. Hot water expands on the molecular level, with the excited water molecules spaced further apart than in colder water. This means that hot water can actually freeze faster than an equal volume of colder water, further increasing the risk of freeze damage affecting untreated hot tubs. Winterization focuses primarily on removing all of the water from your spa and its fittings, methodically preparing it to resist the cold weather.

How to Close a Hot Tub for Winter

Before you start to winterize your hot tub, make sure safety is a priority. Thousands of lives are lost annually to accidental drownings, and a lack of safety barriers is a contributing factor in the majority of these deaths. Until it is completely drained, your spa is a drowning hazard for small or physically compromised bodies, so it should never be left unattended or unsecured. Make sure the gate to your pool fence is closed and secured and a safety net or cover is installed anytime you have to step away. In addition to the drowning risk, understand that your hot tub relies on both electricity and water. While engineered to safely use these two resources while in operation, care should be taken to avoid the risk of electrical injury throughout the process.

Shut Off Power to the Spa and Accessories at the Source

Electricity and water don’t mix when it comes to maintenance, so take power out of the equation. This goes beyond simply not turning on your hot tub. Shut off the breaker that leads to the tub if it’s hardwired into your home’s electrical system, otherwise, unplug the spa at the wall outlet. If other people are home while you’re working on the spa, make sure they know you are intentionally disrupting power to prevent accidental shock risks. Beyond your own health and safety, this protects your tub, as some spa equipment can be damaged if run without a sufficient amount of water present, such as the heating elements that would normally keep the water warm.

Drain the Water From Your Hot Tub

Large empty hot tub

Don’t add sanitizer to your pool the week before you winterize your hot tub. While sanitized spa water is safe to soak in, it’s not meant for drinking, and pets, birds, and other animals may decide your draining water is the perfect chance for a good drink of water. This short period of time shouldn’t be enough to allow contaminants a chance to proliferate, but it can lower the levels of your chemicals to less harmful levels before it’s returned to groundwater or municipal drainage.

Remove Water from Spa Equipment

Ensure the heater, blower, and pump are all switched off, then restore power to the hot tub at the breaker or wall outlet. With your spa cover on, run the blower for a few minutes to clear the lines. Then switch off the blower and cut power to the hot tub once again. Loosen the pump and heater unions, draining the water from them. Remove your spa’s filter, clean it, and set it aside to dry. Finally, open any drain slugs or valves for the pump, heater, or blower to allow the last of the water to drain from them. 

Clear the Lines

Using a leaf blower, air compressor, or wet/dry vac with a hose attached to the exhaust port, blow out your water lines by forcing air briefly into each drain, union, or jet. This gets the last of the water out of the system so there isn’t anything left for winter to freeze. Do it one more time, as this will ensure some of the most vulnerable and difficult-to-service parts of your hot tub are protected.

Clean the Shell

Hot tub with a cleaned cover on top

Using a soft-bristled brush and mild detergent, scrub the hot tub. This is a great time for a deep cleaning, as all the water is out of the way, and you can let the detergent and some elbow grease get everything nice and clean. 

Tighten Unions, Close Valves, and Re-install Drain Plugs

Now that the system is free from water, your hot tub is winterized and you can close it up. Reinstall the dry filter, close drain valves and plugs, and retighten the unions to close off your spa’s system. This will help prevent atmospheric moisture from entering the system and building up. You can also reinstall your spa cover to keep out debris and prevent access. While you can restore power to your tub after making sure all switches are still set to the off position, you shouldn’t need to under most circumstances. Leaving power interrupted helps ensure no accidental activation can occur.

What About the Anti-Freeze?

If you close your hot tub for the winter properly, making sure all water is removed from the spa and its systems, you shouldn’t need it. Anti-freeze is a liquid additive that serves the same purpose in your spa as it does in your car. It keeps water from freezing. If there’s no water, it shouldn’t be necessary. If you decide to use it out of an extremity of caution, generally speaking, one gallon of anti-freeze is added each to the filter and pump housings. When you factor in both treatment and cleanup, that’s a lot of money and work to winterize your hot tub that just isn’t needed when you eliminate the water properly.

Improve Your Hot Tub Safety Over the Winter

When you close your hot tub for the winter, it’s also a great time to make sure you’re ready for safe spa usage when it reopens in the spring. Your local installer is ready to tailor a spa protection plan to your property’s needs, with safety nets and removable mesh fences that can help reduce the risk of accidental drowning. Request your free quote from Lifeguard on Duty today.

Like this article? Share it!

Latest Articles

Check out our collection of blog articles to learn more about pool safety today!

Backyard swimming pool with multiple waterfalls and enhanced lighting
Swimming Pool Water Features to Enhance Your Backyard
Pool water features give you an upgraded swimming pool experience with a better look, immersive sounds, and fun...
Empty swimming pool in a residential backyard
Swimming Pool Remodeling and Maintenance Tips
Learn how to keep your pool protected during a swimming pool remodel and our pool maintenance tips to spot areas...
5 kids wearing goggles are locked arms in a swimming pool
How to Beat the Heat: Tips to Stay Cool This Summer
Your pool can be a great way to beat the summer heat while staying safe. We cover the top tips for summer pool...

Make Your Backyard A Safe Place Today!

Complete the information below and one of our installers will be in touch with you as soon as possible to discuss the pool safety options available to fit your needs & budget

Contact Info