How To Winterize Your Hot Tub Or Swim Spa

In our opinion, winter is the best time of year to use a hot tub or swim spa. Not everyone feels this way, however. If you’re planning on shutting down your hot tub or swim spa for the winter you’ll want to make sure that it is properly winterized first.

How To Winterize Your Hot Tub Or Swim Spa In 6 Steps

1. Clean The Plumbing

The first thing you should do when winterizing your hot tub or swim spa is to clean out the plumbing. For this you will need a specialized hot tub / swim spa plumbing cleaner. Simply add the cleaner 30-60 minutes before draining the water. Make sure your jets are on during this time to allow the cleaner to flow through the plumbing and break up any oils and lotions that have built up.

After a couple of minutes you should notice a thick foam start to build up on the surface of the water. This foam will be dark grey, brown or black in colour. Suck up this foam with a shop vac until it begins to turn white. Once the foam turns white you can begin draining the water.

Learn More: What is Biofilm?

2. Drain The Water

Once your plumbing has been cleaned out you will need to shut the power off at the GFCI and begin draining your hot tub / swim spa. Once the water is fully drained, get a shop vac out and try and drain as much water out of the plumbing as you can.

You can do this in a number of ways:

• Remove the jet faces one by one and vacuum out the ports behind each jet.
• Unscrew and remove the diverter valves and vacuum out the plumbing underneath.
• Crack the diverters on either side of the pump and vacuum out the plumbing on either side.

3. Remove & Clean Your Filters

An important thing to do when draining your hot tub or swim spa is to clean the filters. Cleaning your filters is essential to keep your hot tub running efficiently, prevent water quality issues and avoid potential damage to your pumps.

To clean your filters you will need to purchase a specialized hot tub filter cleaner, typically a powder. Dissolve the cleaning powder into a bucket of water large enough to fit your filter. Put your filter in the bucket with the cleaning solution and let sit overnight. When the time is up, remove the filter and rinse it with a garden hose. You’ll then want to let it fully dry and store it inside for the winter.

4. Clean The Surface

After you’ve drained as much water as you can from the plumbing (you will never get all of it) you should give the acrylic surface of your hot tub / swim spa a clean. You can do this with an acrylic cleaner designed for hot tubs / swim spas. Regular household multi-surface cleaners are not recommended as they can negatively affect your water balance and contain sudsing agents that can cause the water to foam when you reopen it in the spring.

5. Clean The Cover

The last part of your hot tub / swim spa that you should clean is the cover, especially the underside of the cover. Because the underside of the cover is in a hot, damp environment there is a tendency for mildew to grow on it over time, especially in the seams.

To remove this mildew and clean the hot tub cover, simply spray it with a non-sudsing hot tub cleaner like Clean & Perfect and remove it with a paper towel or cloth.

Learn More: Hot Tub Cover Replacement Guide

6. Cover The Hot Tub / Swim Spa

Once everything has been cleaned, it’s time to put your hot tub or swim spa away for the winter. To do this we recommend covering the hot tub / swim spa with a tarp or cover cap. This does two things for you:

1. It prevents water from entering your hot tub or swim spa and freezing over the winter.
2. It helps to prevent damage to your cover.

Potential Risks With Winterizing Your Hot Tub / Swim Spa

When you shut down your hot tub or swim spa for extended periods of time you introduce potential for damage. For most of the year this damage comes in the form of the rubber gaskets and o-rings drying out and cracking; causing leaks to form in various parts of the plumbing. To prevent this from happening, you can remove the gaskets and o-rings found around the pumps and heaters and store them in a jar of water to keep them wet until you’re ready to open it back up.

Plastics can also expand and contract with changes in temperature; which can loosen fittings and cause leaks when you reopen the hot tub or swim spa.

Closing your hot tub or swim spa in the winter introduces a more serious potential issue; freeze damage. As water freezes it expands. This expansion has the force required to crack plumbing, break unions and cause other permanent damage to your hot tub or swim spa. There are a few things you can do to reduce the potential for freeze damage:

• Get as much water out of the plumbing as you can.
• Add some antifreeze to the plumbing to try and prevent the remaining water from freezing.
• Cover the entire hot tub / swim spa in a tarp or cover cap to prevent more water entering over the winter.
• Unscrew the fittings around your pump and filter to give any water that does pool in the plumbing a way out before it freezes and cracks the plumbing, or damages your pumps or heaters.

How To Reopen Your Hot Tub / Swim Spa

To reopen your hot tub or swim spa in the spring you will need to:

• Uncover your hot tub / swim spa.
• Reconnect any fittings that you have have unscrewed and add back any gaskets or rings that you may have removed.
• Check all the fittings to ensure that they’re tight.
• Fill up the hot tub / swim spa with water.
• Turn the power on. If you put any anti-freeze in the plumbing you will want to run it for a few minutes then drain and refill it to flush the anti-freeze out of the system.
• Put the filters back in.
• Treat the water with your start up chemicals once the water heats up to at least 70 Fahrenheit.

So Should You Winterize Your Hot Tub Or Swim Spa?

In general we don’t recommend closing your hot tub or swim spa for the winter. Even if you do everything right, there’s simply no guarantee that you won’t have issues when you reopen it in the spring. If you do still want to close your hot tub or pool for the winter, following the steps that we outlined today will give you the best chance to safely winterize it.