1. Let the Chemicals Dissipate
Before you drain all the water into your yard or other location, you need to allow the chemicals levels to drop.
This mostly applies to chlorine and other sanitizers, which can be toxic to plants and wildlife, but none of the chemicals you use in your spa are made to be released anywhere but into your hot tub.
Give it a few days, and test the water. Once the chlorine (or other sanitizer) level has dropped to zero, you can begin winterizing your hot tub.
2. Turn Off the Breaker
It’s not enough to just turn the hot tub off. Make sure there is absolutely no power getting to your hot tub. You can also simply unplug it if it’s not hard-wired.
Important: This cannot be stressed enough. Do not skip this step. Electricity and water do not mix, and failing to cut power to the hot tub will put you—and anyone who may be helping you—in danger during this process. Safety first, always.
3. Drain the Hot Tub
Remove the drain cap, and attach the garden hose to the drain spout. Make sure the other end of the hose is in an appropriate place to drain all the water. Remember, you’ll be releasing roughly 400 gallons of water. Make sure the drainage area can accommodate that amount. Allow the spa to drain.
If you want to drain the spa more quickly, you can pump the water out with a sump pump. Keep an eye on the hot tub so the pump doesn’t run dry. Also remember to remove the drain cap when you’re done using the pump.
Or, if you want to really speed the process up, you can do both.
An inch or two of water will remain at the bottom of the hot tub. Don’t worry about it right now. You’ll get to it later in the process.
Note Keep the drain cap somewhere safe so you’ll be able to find it easily when you’re ready to refill your hot tub. If you misplace the drain cap, don’t worry. You can get a replacement.
4. Drain The Blower
If your hot tub has an air blower you must drain the water from it before continuing.
Turn off the heater. You must never run the heater when the hot tub is empty, so make sure the switch is in the off position.
Cover the hot tub. Put the hard cover in place, just as you normally would.
Turn the breaker on. Or plug the hot tub in, if you just unplugged it.
Turn the hot tub on. This will run the blower. Let it run for about 30 seconds to remove any water from inside it.
Turn the hot tub off.
Turn the breaker off. Or unplug the hot tub.
Remove the cover. Then get back to winterizing your hot tub.
5. Loosen the Unions on the Pumps and Heater
Open the access panel in the cabinet, and locate the pump(s) and heater. Loosen the unions to allow water to drain from the plumbing lines.
If the pump(s) has a drain plug, remove that as well, and allow any water inside the pump to drain out.
6. Remove and Clean the Filters
You don’t want to leave the filters in place over the winter. You also don’t want to store dirty filters. Remove them, and take this opportunity to clean them.
You could use regular filter cleaner, but since you’ll be storing the filters for weeks, possibly months, we recommend going a little further and putting them in a chemical soak for 24 hours, or at least overnight.
If the filters are beyond cleaning, just dispose of them, and start with new filters when you open your hot tub next season.
Once you’ve removed the filter, remove any water left in the filter well. You can do this with the Shop-Vac, sponges, or towels.
7. Blow Out The Lines
When you think about how to winterize a hot tub, clearing the water from the lines is the key. If this isn’t done correctly or completely, you may as well not winterize at all.
Leaving water in the plumbing lines over the winter can cause the water to freeze and expand, which can cause the lines to crack or burst. You want your hot tub to be completely empty over the winter, and that means every part of it, not just the tub.
Turn the Shop-Vac’s setting to blow. Insert the hose into every drain, union, and jet, and the filter cavity. Blow into each spot for 10 to 15 seconds to force the water out of the lines and into the tub.
When you finish, repeat the process. Again, you don’t want any water in the lines.
8. Remove the Remaining Water
This is why we said not to worry about a little bit of water left in the tub when you drained it. Now you can remove all the remaining water at once. We’re all about efficiency!
Depending on how much water is now in the tub, you may want to use the sump pump again, and then use the Shop-Vac to pull out whatever the pump can’t get. If it’s just a little water, the Shop-Vac should be able to handle it all.
9. Clean The Shell
This will be the easiest clean you ever did on your hot tub. It’s easy when there’s no water in the way!
Use non-abrasive sponges and hot tub cleaner that doesn’t require rinsing to clean the shell. Wondering how to clean a hot tub without chemicals? You can absolutely use non-toxic products like vinegar and baking soda. Either way, make sure to get all the nooks and crannies.
If you find a ring of hot tub scum where the waterline was, you may need to soak it a bit with the hot tub cleaner before scrubbing it away. You may also want to use a little diluted bleach to kill any bacteria that may be hiding in it.
Don’t forget to remove the headrests and clean under them too. You may find a little water hiding under there, just waiting to grow mold over the winter.
10. Clean The Cover
You probably give your hot tub cover a good wipedown when you do your regular cleaning. But to winterize your hot tub and keep it closed for a few months, that cover needs to be clean.
If your hot tub is outside, use a good cover cleaner that’s also a protectant to shield the cover from the sun’s rays. Clean the underside, the top, and the sides, getting into the crevices created by seams.
Let it air dry, or wipe it dry with a towel. You don’t want to close up any moisture when you cover your hot tub. That’s an invitation to mold and mildew.
11. Secure the Cover
Once the cover’s dry, place it over your spa. If it locks, lock it to prevent anyone or anything from climbing into the hot tub during the winter. All kinds of little critters would love to find a cozy place to stay out of the snow and ice.
Even if your hot tub cover locks, it’s a good idea to further secure it with wind straps to ensure it stays put, even in the harshest winter weather.
12. Antifreeze
After everything is complete, pour R/V Antifreeze in all of you lines and filters to protect against water entering the system and freezing.