As winter approaches, hot tub owners face a critical decision: keep their spa running or winterize it. If you’ve chosen to give your hot tub a rest, this guide is for you.
Properly winterizing your hot tub is more than just draining it; it’s a crucial process to protect your investment from the harsh winter elements. Failing to do so can result in costly damage from freezing temperatures.
This step-by-step guide will walk you through the process of winterizing your hot tub, ensuring it remains in pristine condition for the next season. We’ll cover everything from initial preparations to final checks.
What “Winterizing” a Hot Tub Actually Means
Winterizing a hot tub means preparing it for a period of inactivity during the colder winter months. It involves more than simply draining the water.
The main goal is to prevent freeze damage, since low temperatures can cause trapped water to expand, crack pipes, and damage key components.
A thorough winterization removes water not only from the shell, but also from the plumbing lines, pumps, and heater. By removing any remaining moisture, you reduce the risk of freezing, expansion, and costly repairs when you are ready to use the spa again.
Should You Winterize or Keep Your Hot Tub Running?
The decision to winterize your hot tub or keep it running is a common dilemma. Both options have their pros and cons, and the right choice depends on your personal preferences, usage habits, and local climate.
When Winterizing Is the Safer Choice
For many hot tub owners, winterizing is the most practical and safest option.
If you live in an area with harsh winters and extended freezing temperatures, winterizing helps prevent serious damage. When water freezes, it expands, which can crack pipes, strain pumps, and damage the heater.
Repairs can be costly and time-consuming. If you do not plan to use your hot tub often during winter, winterizing can also reduce energy costs by eliminating the need to keep water heated.
It also minimizes cold-weather maintenance and provides peace of mind until spring.
When Keeping It Running Makes Sense
Winterizing is a safe choice for many owners, but keeping your hot tub running can make sense in the right conditions. If you live in a mild climate where temperatures rarely stay below freezing, the risk of freeze damage is lower, so winterizing may be unnecessary.
It is also a good option if you use your hot tub year-round and want warm soaks during winter. To help retain heat, consider a well-fitting hot tub cover and an additional thermal layer, such as a 7-foot thermal blanket. Many modern spas also include freeze protection modes.
Best Time to Winterize
Timing is everything when it comes to winterizing your hot tub. The ideal time to start the process is before the first hard freeze of the season.
A hard freeze is commonly defined as temperatures reaching 28°F or lower for an extended period—plan to winterize before that first hard freeze hits your area. Waiting too long can result in a frozen hot tub, which can cause significant damage.
Also, check your local weather forecast and plan to winterize your hot tub on a day when temperatures are still mild. This will make the process more comfortable for you and ensure that you’re not rushing to beat a cold snap.
By being proactive, you can protect your hot tub and avoid any unpleasant surprises when winter arrives.
Tools and Supplies Checklist
Before you begin the winterization process, it’s essential to gather all the necessary tools and supplies. Here is a checklist of what you will need:
- Plumbing line flush: (From your local spa supply store) to help remove buildup before draining.
- Garden Hose With a Nozzle: For draining the hot tub and rinsing it out.
- Submersible Pump: To remove the last few inches of water from the tub.
- Shop-Vac or Wet/Dry Vacuum: To blow out any remaining water from the plumbing lines and jets.
- Towels and Sponges: For cleaning and drying the hot tub shell.
- Filter-cleaning solution: (or follow your spa brand’s guidance) so filters can dry fully before storage.
- Non-toxic RV/marine antifreeze: (propylene-glycol based) is optional for extreme cold—never use automotive antifreeze.
- Wrenches and Screwdrivers: To open the equipment bay and access the drain plugs.
- Safety Goggles: To protect your eyes from any splashing water or chemicals.
- Owner’s Manual: For specific instructions related to your hot tub model.
How to Winterize a Hot Tub
Now that you have gathered all your tools and supplies, it’s time to begin the winterization process.
Read the Owner’s Manual and Plan the Workflow
Before unplugging anything or draining the water, review your hot tub’s owner’s manual. Each model is different, and the manual outlines the correct winterization steps for your unit.
It will also point out the locations of drain plugs, pumps, and other key components you will need to access. Taking a few minutes to understand your hot tub’s layout helps you plan the process, stay organized, and reduce the chance of missing an important step.
Prep the Water and Purge the Plumbing
Before draining your hot tub, clean the plumbing lines to remove buildup that collects over time, such as biofilm and other contaminants.
Add the plumbing line cleaner to the water per the product instructions, then run the jets for the recommended time to circulate it through the entire system. This helps loosen and flush out residue inside the pipes.
Once the cycle is complete, you can drain the tub knowing the plumbing is cleaner and ready for storage.
Shut off the Power at the Breaker
Safety comes first when working on a hot tub. Before draining water or touching any electrical parts, shut off power completely.
Do not rely on the control panel switch. Go to your home’s main breaker box and turn the hot tub breaker to the OFF position to cut power at the source and reduce the risk of electric shock.
If you have a voltage tester, use it to confirm the power is off before proceeding.
Remove, Clean, and Store Filters Indoors
Your hot tub filters keep the water clean, so remove them before draining and clean them thoroughly. Rinse off debris with a hose, then use a filter cleaner to break down buildup.
After cleaning, let the filters dry completely. Store them indoors in a dry place to protect them from freezing temperatures and moisture, which can cause cracking or damage.
Taking this simple step helps extend filter life and keeps them ready for use when you reopen the hot tub in spring.
Drain the Tub Completely (Fast and Safely)
With the power off and the filters removed, it is time to drain the hot tub. Most spas have a built-in drain, but it can be slow. To make the process easier, use a dedicated drain tool such as the QuickDrain Hand Held Drain.
You can also speed up the process with a garden hose or a submersible pump. After draining, remove any remaining water from the footwell with a shop vac or bucket to ensure the tub is as dry as possible.
Drain Blower and Air Lines (If Equipped)
If your hot tub has an air blower (the feature that creates bubbles), you will need to clear it too. Use a shop vac on the blow setting to push air through the air lines and expel any trapped water.
Check your owner’s manual to locate the blower and air system access points. This step is critical because residual water in the blower or lines can freeze, expand, and crack components, leading to costly repairs. Make sure the air system is completely dry.
Open the Equipment Bay and Drain Pumps/Heater
Next, drain the equipment bay, where the pumps, heater, and other key components sit. Open the access panel and locate the drain plugs on the pumps and heater. Many hot tubs have two pumps, each with its own plug.
Place a bucket underneath to catch water, then loosen and remove the plugs (you may need a wrench or pliers). Let everything drain fully. This step is essential because any trapped water can freeze and damage costly equipment.
Blow/Vacuum Out Every Line, Jet, Suction, and Cavity
Even after draining the pumps and heater, some water can remain in the plumbing lines, jets, and suction fittings. Use a shop-vac to clear it out. Set it to blow and push air into each jet and fitting, forcing trapped water out into the footwell.
Keep going until you no longer see water coming out. Then switch the shop vac to vacuum mode and remove the pooled water. This extra step helps prevent freeze damage in hidden lines.
Optional: Add Non-Toxic Antifreeze for Extra Protection
If you live in a very cold climate, adding non-toxic RV/marine antifreeze to the plumbing can provide extra protection. This step is optional, but it can help safeguard against freeze damage.
Use only antifreeze designed for plumbing systems; never use automotive antifreeze, which is toxic and can damage components. To apply it, pour antifreeze into the filter housing and each jet to displace any remaining water. In spring, flush the lines thoroughly before refilling.
Clean and Dry the Shell, Cabinet, and Cover
Once the tub is fully drained, clean it thoroughly. Use a soft cloth or sponge with a mild, non-abrasive cleaner to wipe down the shell and remove dirt, residue, and grime. Clean the cabinet and hot tub cover as well.
When finished, dry the shell, cabinet, and cover completely with towels. Keeping everything dry helps prevent mold and mildew during storage. This quick cleanup also makes spring reopening easier, since your hot tub will be ready to refill and enjoy.
Secure the Cover Against Wind, Moisture, and Snow Load
Your hot tub cover is your primary barrier against wind, moisture, and snow, so ensure it is secure before winter sets in. Inspect it for rips, tears, or weak seams, since a damaged cover will not insulate or protect properly.
If it is in good condition, position it evenly and fasten the locking straps, such as a spa cover wind strap. For extra protection from weather and debris, you can even add a custom spa cover cap over the top.
Additionally, if you’re in heavy-snow areas, place a sturdy sheet of plywood on top to spread the weight and help prevent sagging or cracking.
Final Checklist and “Walk-Away” Check
Before you call the job done, do a quick final checklist. Review your winterization plan and confirm each step is complete: power is off, the tub is fully drained, plumbing lines are blown out, and the cover is locked down.
Open the equipment bay one last time to confirm that the drain plugs are open, the water has emptied completely, and there are no visible leaks. This short walk-away check helps you catch small misses now and avoid bigger problems later.
What to Do If Your Hot Tub Freezes
Discovering your hot tub has frozen is stressful, but the goal is simple: stop further damage, thaw slowly, and check for leaks before you try to run anything. When in doubt, contact a qualified spa technician.
- Shut off power if water isn’t circulating.
If the pumps can’t move water, turn the spa off at the breaker/GFCI to avoid damaging the pump or heater. Keep the cover closed to hold any remaining heat. - Add warm water to help loosen surface ice (avoid hot water on the shell).
If there’s ice on the surface, carefully break a small opening and add warm water to help thaw gradually. Do not pour hot/boiling water directly on the acrylic shell, which can damage it. - Thaw the equipment area gently and safely.
Open the cabinet access panel and warm the equipment area slowly. If using a small heater, only do so when you can monitor it constantly, plug it directly into a GFCI outlet, keep it at least 3 feet from anything combustible, and never leave it unattended. Optional alternative: Use a hair dryer on low heat, keeping it moving—never concentrate heat on one spot. - Inspect for freeze damage once thawed.
After everything is thawed, use a flashlight to check the pump, heater, filter area, unions/fittings, and visible plumbing for cracks, leaks, or wet insulation. - Restore power only when you’re confident water can flow.
Once thawed and the water level is correct, restore power and confirm normal circulation. If the GFCI won’t reset or anything looks damaged, stop and call a pro. - Call a qualified technician if you see leaks, cracks, or persistent errors.
Freeze damage can hide in fittings or equipment. A technician can pressure-test lines and prevent a small crack from becoming a major failure.
How to Reopen Your Hot Tub After Winterizing
When warmer weather returns, reopening your hot tub after winterizing is usually straightforward.
- Close Everything Up. Reinstall the drain plugs you opened and make sure all fittings are secure.
- Reinstall the Filters. Put clean, dry filters back in place.
- Refill With Fresh Water. Fill the tub to the recommended level.
- Flush if Antifreeze Was Used. As the tub fills, flush the lines to remove any antifreeze residue.
- Restore Power and Circulate. Turn the power back on and run the jets to circulate water through the system.
- Balance Water Chemistry. Test and adjust sanitizer, pH, and alkalinity as needed.
- Do a Final Leak Check. Inspect the equipment bay and plumbing before regular use.
When to Call a Professional
While winterizing and reopening a hot tub can be a DIY project, there are times when it’s best to call a professional. If you’re not comfortable with any step in the process or don’t have the necessary tools, a professional can ensure the job is done correctly.
Additionally, if you notice any damage to your hot tub, such as cracks or leaks, it’s best to have a professional assess the issue. They will have the expertise to diagnose the problem and make the necessary repairs, ensuring your hot tub is safe and ready for use.
Frequently Asked Questions
Do You Need Antifreeze to Winterize a Hot Tub?
Usually not, if the tub is completely dry. However, RV/spa-grade antifreeze can be an optional extra protection, especially in very cold climates. Avoid automotive antifreeze due to its toxicity.
At What Temperature Will Hot Tub Pipes Freeze?
Freeze risk increases any time temperatures stay below 32°F (0°C)—and becomes much more serious during a hard freeze (around 28°F or lower), especially if water isn’t circulating.
How Long Can a Hot Tub Sit Unused in Winter?
A properly winterized hot tub can remain unused for the entire winter. If not winterized, an unused, unpowered hot tub can freeze and sustain damage within a few hours in freezing weather.
