Hot Tub Drain and Fill

Drain and Fill Your Hot Tub

A drain and fill of your hot tub is a fairly simple process. It does, however, involve a series of steps that begins with gathering the equipment you’ll need to do the job.

Equipment Needed

  • Garden Hose
  • Submersible Pump (optional)
  • Clean Rag
  • Spa Shell Cleaner
  • List of suggested products to use at the bottom

Optional Line Flush.

It is our recommendation that, at least once per year, a line flush is performed prior to draining & refilling your hot tub. Flushing the lines will remove the buildup & biofilm that settle in your tubs plumbing. It is in this moist and warm environment that bacteria & algae flourish.

  1. When flushing your lines it is imperative that the following items are completed first:
      • Remove your Salt Cell or Salt Cartridge (if applicable)
        • This is also a GREAT time to clean your Salt Cell (if applicable)
      • Remove your Silver Ion Cartridge
      • Remove your @Ease SmartChlor & Mineral Cartridges (if applicable)
  2. At this point, you can safely add the Clean Start line cleaner to your tub, turn the jets on high and allow it to run, with the cover open, for a minimum of 30 minutes – longer if it has been more than a year since the lines have been cleaned.
  3. Next, turn off the power to the hot tub at the main disconnect box – now you are ready to drain your tub!
  4. This can be accomplished in roughly 1 hour by using a submersible pump, if available, or in roughly 2-3 hours using the tubs drainage spigot(s).

Clean your filters.

Cleaning your spa’s filters is even easier than cleaning the shell and should be done monthly. Check out our video on how to clean your filters here.

Drain your hot tub. 

Depending on the size of your spa, it should take around an hour to drain using the hot tub’s drainage spigot, or ten minutes to drain with a submersible pump.

To drain using the spigot:

  1. Turn the power to the spa off at the circuit breaker. You don’t want the pumps or jets to run while there isn’t any water in the spa.
  2. Locate drainage spigot. Your spa model may have two spigots, a primary and auxiliary spigot. Use the primary spigot to drain most of the water, and then open the secondary spigot to drain the internal bleed lines.
  3. Attach the garden hose to the spigot, being careful not to cross-thread. The spigot’s threads will be plastic and may break if you apply too much force. Ensure that the hose is placed in such a way that the water drains to the desired area.
  4. Open the ball valve on your spigot so the water can drain.
  5. Blowout the pipes water all the water has been drained. Use a shop vacuum to blow out and suck out the excess water in the plumbing lines.

To drain using a submersible pump:

Submersible Pump to Drain Tub

  1. Turn the power to the spa off at the circuit breaker.
  2. Place the pump inside the spa.
  3. If your pump’s outflow hose isn’t long enough to reach a drain, connect it to a garden hose.
  4. Turn the pump on and let the spa drain. Ensure that the hose is placed in such a way that the water drains to the desired area.
  5. When the hot tub is empty, turn off the pump, remove it from the spa, detach the hose, and return it to storage.
  6. Blowout the pipes. Use a shop vacuum to blow out and suck out the excess water in the plumbing line.

Clean your empty spa.

Once the water is drained, you can easily inspect and wash the shell’s interior, and remove and clean your spa filters before refilling it.
Fortunately, your spa’s shell is designed to resist dirt and stains, and cleaning it requires no more than a soft, damp rag. Many household cleaners can be harmful to your shell, so check your owner’s manual before using any. When finished, rinse the shell with clean water.

Refill your hot tub.

Start by closing the ball valve & replacing the cap on the tub’s drain spigot(s).

Next, identify the standpipe in the filter compartment – the one that is associated with the circulation pump, it will often have a different color cap than the other filters. Your owner’s manual will tell you exactly where to find the standpipe in your spa. Depending on the size of your spa and the size of your refill hose, it should take about as long to refill it as it took to drain it from the spigot.

  • You may choose to use a Clean Screen Filter to remove metals and minerals from your source water before it fills the tub.
  • If you have a saltwater hot tub it is recommended to fill the tub with pre-softened water if available. If not a Vanishing Act Pillow will need to be used, to lower the calcium hardness in the water, as part of the balancing process.

Place the garden hose down into the standpipe of that main filter & turn on the water. This allows for the plumbing lines to be filled with water before the well of the tub & will prevent an air-lock or air pockets in the plumbing.

  • An airlock is an air bubble that gets trapped inside your hot tub’s plumbing as it’s being filled with water. One or more air bubbles can cause the spa to work improperly and could damage jet and circulation pumps if you run them with air inside. If you do run into an airlock check out this video from another deal on how to remove one.

Once the water level has reached the point of fully covering the top row of jets it is safe to turn the power back on at the main disconnect.

You can now reinstall your freshly cleaned filters, your Salt Cell or Salt Cartridge, & the Silver Ion Cartridge.

Allow the temperature of your tub to reach at least 90 degrees before beginning to add any sanitizers or balancing chemicals.

  • It is highly recommended that each time a tub is drained and refilled that you also clean & protect the hot tubs cover with Cover Shield.
  • The shelf life of your test strips is 1 year, so it may be time to replace those to ensure the best water quality.


There you have it! Your hot tub drain and fill is complete. Now you just have to wait for the water to heat up and you are ready to go!

Couple in Spa

Product Suggestions

Clean Start or Ahhsome

Clean Screen Filter

VanshingAct Pillow

Test Strips and Salt Test Strips

Spa Salt

FreshWater Salt Cartridge

Silver Ion Cartridge

Filter Cleaner

Cover Shield

Aqua Mitt

Scum Duck


Did you know that HotSpring Spas & Pool Tables 2 will do your hot tub drain and fill for you?!?!?! Call 701-532-0784 to learn more.