Draining and Refilling Your Hot Tub

hot tub

Most spa companies suggest you empty and refill your spa water every three to four months. Water can sometimes get unruly and difficult to balance so a hard-reset (i.e. refilling) can greatly aid in the process. Even though this is the recommendation, it can be tricky when trying to figure out how to go about it. What are the steps? How difficult is the process? We’ve tried to break it down for you in this post about draining and refilling your hot tub.


Before emptying your water, you’ll want to do a few things:

Make sure the power to your unit is OFF. Electrical safety is vital when dealing with any appliance, hot tubs included. This means making sure both the heater and main power supply are not turned on. It’s a good idea to take out your spa filters at this time and give them a good cleaning while it’s empty.

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Different spa units have different kinds of drains.

A common emptying method in certain models of spas are built-in gravity drains. These are usually on the outside of the hot tub coming out of the base or inside on outer panel. You activate it by removing the cap or plug and and hooking up a hose to redirect the emptying water or just let it empty itself if it’s not running the risk of ruining anything it may drain onto. In older models, this method may take a while. In newer tubs, they’ve made this method increasingly efficient and your tub may drain more rapidly than you’d think.

Tip: if the water hasn’t been hyper-chlorinated the day before or isn’t heavily sanitized, feel free to empty your water onto your lawn or near fruit trees—people have actually reported their lawn being lushest when hot tub water was emptied onto it. Some cities like Las Vegas require you to empty water into the local drain systems so make sure you stay abreast of local laws.

The main issue with these types of outer drains is that they are vulnerable to breakage and leaking because they are external and under high pressure.

Some hot tubs don’t have drains because they’re trying to avoid these issues. If this is the case, there are two ways to empty the tub. The cheaper way is to using suction to siphon the water out of your tub with a regular garden hose. You get the flow of water started by either sucking on one end of the hose pipe (make sure it’s clean) or by lifting up the end inside the hot tub and placing back into the spa. Once the flow has started, you can leave the hose to drain where you wish.

This method might not be fast enough for some speed demons. In that case, you might consider investing in a submersible pump or a sump pump. This is a water pump that can drain hot tubs in a matter of minutes. Simply plug in, place in the deepest part of the hot tub and wait for it to finish.

Tip: Keep a watchful eye during this process because you don’t want the pump to stay running without water flowing out of it. It might ruin the motor.

If you’re draining the tub for several months, you’ll want to keep the filters indoors so they don’t get additional wear. You’ll also want to drain the lines and make sure there’s no residual water hanging around in the plumbing. Once the hot tub is empty, ensure your drain is left open to prevent the pipes cracking due to freezing in winter.



We covered some of this in our hot tub maintenance post, but once your spa is devoid of water, now is an excellent time to clean the interior. This is most easily done from inside the tub so you’re not leaning over the sides. Use a hot tub specific cleaner that isn’t abrasive and use a soft cloth to wipe it down. Don’t use anything soapy that will cause foaming when you refill your tub.

If you need to clean off scum or calcium deposits, you may want to use a soft nylon brush.

After you’ve wiped down the interior of the spa, do a quick rinse to remove any lingering cleaner.



After a successful cleaning, it’s time to refill your tub. At this point, you’ll want to cap any drains and replace plugs you may have taken out in order to empty it. Replace your filters that you’ve hopefully cleaned. If your local water is heavy in minerals that makes adjusting your water difficult, consider adding a pre-filter. They attach to the end of the hose and help to eradicate any hard minerals in the water supply. You’ll also want to flush your hose out for thirty seconds to make sure that no stale water that has been resting in the hose or pipes is filling your tub.

Tip: Don’t refill with hot water—this will send your sensors on the fritz.

It’s best if you refill with the hose down in the center of the gray standpipe in the filter compartment. This will reduce airlocks in the equipment and the water will circulate through the heater. Don’t turn on your equipment until the spa is full, about 1 ½ inches above your highest jet. At this point you’ll want to turn on the power, heater, and jets to purge any remaining air from the plumbing. Make sure your temperature is properly set.

Now just add your chemicals and you’ll be ready to soak in no time!

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