Draining your spa allows you to replace the water and clean the shell. It is also an essential step when closing your hot tub for winter. Depending on your equipment, you can empty the spa using its drain valve, a submersible pump, or a siphon system such as a Quick Drain.
This guide covers the main draining methods, the precautions to take, and what to do before refilling your spa or winterizing it.
How Often Should You Drain Your Spa?
Spa water needs to be replaced regularly. Every three to six months is a general guideline, but the right schedule depends on your manufacturer’s recommendations, how often you use the spa, the number of bathers, and water quality.
More frequent use may require more frequent water changes. If the water remains cloudy, foamy, or difficult to balance despite proper maintenance, check whether it is time to replace it.
For winter closing, draining the shell is only part of the process. Water must also be removed from the plumbing and equipment to protect the spa against freezing.
Before You Start: Essential Precautions
Before draining your hot tub:
- Turn off the spa at the circuit breaker. Its pumps and heater must not operate without sufficient water.
- Check the owner’s manual for model-specific draining instructions.
- Choose a discharge location that complies with municipal regulations. Do not assume spa water can be drained into the street or a storm drain.
- Avoid draining an outdoor spa in freezing weather without an appropriate winterization procedure.
- In hot weather, avoid leaving the empty shell exposed to direct sunlight for extended periods.
Have your drainage hose, soft towels, and any other necessary equipment ready before starting.
Three Ways to Drain Your Spa
1. Use the Spa’s Drain Valve
Gravity draining uses the spa’s built-in drain valve. It requires little equipment but is generally slower than using a pump.
- Locate the drain valve. Depending on your model, it may be inside the equipment compartment or accessible from outside the cabinet.
- Follow the manufacturer’s instructions for opening the drain assembly and removing its cap.
- Attach a garden hose.
- Position the hose outlet at an approved discharge location below the spa’s water level.
- Open the valve and allow the water to drain.
Draining can take several hours, depending on the spa’s capacity, hose diameter, and elevation difference.
The drain valve usually leaves some water in the footwell, seats, and other low areas. You will need to remove this separately.
2. Use a Submersible Pump
A suitable submersible utility pump can empty a spa much faster than gravity draining.
- Connect the discharge hose to the pump.
- Carefully place the pump in the deepest part of the spa without scratching the acrylic.
- Route the hose to your chosen discharge location.
- Connect the pump according to its instructions, using a suitable ground-fault circuit interrupter (GFCI) protected power supply.
- Monitor the water level and stop the pump before it runs dry.
Draining time depends on the pump’s flow rate, the spa’s volume, and the hose setup. Some water may remain in shallow areas or seats.
Keep the spa’s own electrical supply switched off throughout the draining process.
3. Use a Quick Drain or Similar Siphon System
A Quick Drain uses siphon action to remove water without electricity.
- Extend the hose to an approved discharge location below the spa’s water level.
- Place the intake end in the spa.
- Start the siphon according to the product’s instructions.
- Guide the intake toward areas where water remains, keeping it submerged to maintain the flow.
This option is useful when a suitable electrical outlet is unavailable nearby. Never start a siphon by sucking on the hose with your mouth.
Remove the Remaining Water and Clean the Spa
Once most of the water has drained, remove any remaining pools of water with:
- A wet/dry vacuum configured for liquid pickup.
- A small plastic container.
- A soft sponge or towels.
Clean the shell using a product approved for your spa’s surface. Avoid abrasive tools and household cleaners that may damage the finish or leave foaming residues.
Clean the filter cartridges according to the manufacturer’s instructions and inspect them for wear before reinstalling them.
After Draining: Refill or Winterize?
Refilling Your Spa After a Water Change
If you plan to continue using your hot tub:
- Close the drain valve and reinstall its cap.
- Reinstall the cleaned filters and any components removed during maintenance.
- Check that the valves required for operation are in their correct positions.
- Fill the spa to the recommended level, following the manufacturer’s filling method to reduce trapped air.
- Restore power only when the water level is sufficient.
- Follow the spa’s priming procedure and confirm that water flows properly through the jets.
- Check accessible fittings and the drain assembly for leaks.
- Test and balance the water before bathing.
If the pump runs but water does not circulate, switch it off and consult the owner’s manual or a qualified technician. Do not leave it running in the hope that trapped air will clear on its own.
If you notice a leak, turn off the power before inspecting the equipment. Avoid overtightening fittings, and seek professional assistance if the leak persists.
Closing Your Spa for Winter
An empty-looking spa can still contain water in its pipes, pumps, and heater. If that water freezes, it can damage the plumbing and equipment.
Winter closing therefore requires a model-specific procedure to remove trapped water and protect the spa throughout the cold season. Removing visible water from the shell does not replace complete winterization.
If you are unsure how to winterize your model, have a professional handle the closing before freezing temperatures arrive.
Need Help Draining or Closing Your Spa?
Whether you need a seasonal water change or a winter closing, the POSEIDON team can help you care for your spa.
Contact our team or learn more about our spa closing service.
