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How To Drain A Hot Tub?

No matter what the weather is doing, there is always a good reason to get in the hot tub. Those steamy nights under the stars are some of the most memorable, but anyone who owns a hot tub will know that the aftercare is important. This is why a lot of people want to know how to drain a hot tub properly. Not only is maintenance key to the longevity of the tub itself, but hygiene has never been so important.

This is why we have created an informal guide as to how to undertake this practice properly, as well as some other important points.

When Should You Drain A Hot Tub?

Although you can clean the hot tub using the right blend of chemicals to ensure the water is safe to use, there comes a time where you will want to drain it. Even when using quality products to keep everything hygienic and the water pure for months at a time, there is always a stage where draining and refilling is a good idea.

Any spa that uses bromine and chlorine can go around three months before it is best to change the water. Some saltwater systems need less frequent draining and can get by on one water change a year. There is some leeway with these time frames and every spa is going to be different.

The draining process is easy and can be even simpler if using a company to come and drain it for you. Although some purchases come with this service, it is still beneficial to find out how to drain it yourself. Reading our guide will help, but when an expert visits, it can be a good opportunity to observe and ask questions for when it is time to go solo.

Why Drain A Hot Tub?

There are a few common reasons and it’s not just because of the length of time since the last time it was drained and cleaned properly. Another is that the level of TDS (Total Dissolvabloe Solids) becomes too high. This means that the level of the chemicals that have dissolved has got to the stage where only draining the water will suffice.

When levels are too high it can be difficult to bring the optimal balances of the water to the safe zone so balancing pH levels, and controlling scale buildup can be a challenge. Also, you may find you are having to use more chemicals than usual because the TDS levels are too high.

This can be prevented, but it is best to stick to the common timeframe of draining a pool every 3 months (4 at a push).

Is Draining A Hot Tub Difficult?

No, it is not, but it is certainly easier if the hot tub was installed near a drain. Otherwise, all is not lost, you are just going to need a longer hose. The process itself will take around an hour, and will likely get a little faster every time to do it.

So, It Will Take An Hour?

As mentioned, leave an hour aside to complete the draining process, unless using a submersible pump which will make things move a lot faster. These move high volumes of water and are often used to get rid of water in a flooded basement but are particularly useful for draining a hot tub.

How To Drain A Hot Tub

So now the months have passed and it is time to stop stalling, there are a few steps to remember. It all starts with:

The Equipment

Grab everything you need to drain the hot tub including a hose long enough to reach the nearest drain. The more strategic the installation the better this will be. A few old towels or rags never go amiss with this, we are dealing with draining water after all. Also if you want to make life easier, a submersible water pump will come in handy. If not, don’t worry, it is easily done without. A spa shell cleaner is also going to be useful.

Draining A Hot Tub

There are two main ways so we will start with using the spigot:

  • Start by turning the spa off at the circuit breaker. Water and electricity are a dangerous mix so protect yourself with this initial stage. It can be damaging for the pumps to operate when there is no water in the tub.
  • If this is your first time then look up where your spigots are – there are two. The first should be called the primary spigot and this is where you will drain most of the water, with anything remaining internally will be drained from the secondary spigot.
  • Attach the hose to the spigot being careful to ensure the hose runs as level or downhill as possible. Otherwise, you risk leaving water behind as it will not be able to flow out.
  • Be careful to ensure you dispose of water properly as hot tub water containing chemicals can be harmful to the environment if not disposed of correctly.
  • Finally, open the ball valve. This will allow the water to drain.

The following is how to drain a hot tub using a submersible pump. Many of the stages are the same or similar:

  • Again, start by switching off the circuit breaker.
  • Keeping the outflow hose pointing out of the tub, use care to place the pump at the bottom of the hot tub.
  • Make sure the hose included reaches the drain. If this is not the case, attach it to a garden hose or purchase a second hose to give yourself a longer reach. Place it in the drain so the water can be dispersed safely.
  • Turn the submersible pump on and allow the water to drain.
  • Remember it doesn’t take as long as when using the spigot so keep an eye on its progress.
  • Once finished, turn off the submersible pump and remove it.

Clean The Hot Tub

The next stage is your chance to get the hot tub a clean as possible. After months of use without a proper clean, things can get a little dirty. Still, this stage shouldn’t take long and the old towels and rags will come in handy here. Wiping the sides and bottom won’t take long but it is also prudent to clean the internal parts of the hot tub.

You can also clean the filters, something that should be done regularly anyway to ensure you are getting the purest water flowing in and out of the hot tub. Start by removing the cover of the filter and removing it. Some items will be floating, remove them all, and the cartridges. Use a degreaser to soak the filter, clean all items before rinsing and returning them. Finish off by locking the handle.

Refill The Hot Tub

A popular way is to just put the hose back into the tub and fill from the outdoor tap but this approach can be tricky since it leaves the system vulnerable to an airlock. These bubbles get trapped inside the pipes and plumbing of a hot tub and could cause it to damage the jet and other parts. Running air within the pipes can cause havoc so it is best to avoid this method.

Despite it being pretty easy to remove air bubbles, it does add to the time it takes to refill a hot tub, and can damage some of the parts. Of course, the method of getting rid of them will vary depending on what model you have.

It’s usually rather easy to refill a hot tub the right way, just use the correct fill pipe. However, this will be different in every model, some will fill when connected to a hose underneath instead. Always check the manual that came with your brand and model of the hot tub, and alternatively, search online using the model in the description.

Once you get the hang of it, refilling the hot tub shouldn’t take too long and will refill at a similar time that it took to drain.

How Long Does It Take Overall?

The whole process should take up to three hours max. This includes draining, cleaning, and refilling. Of course, the bigger the hot tub, the longer it will take. The good news is that most of the process doesn’t require you to be there. So you can set an alarm to remind yourself to check on its progress. Stay around the house though as it’s never a good idea to refill and go out to the shops, just in case!

Can You Drain A Hot Tub Onto Grass?

The fact that this question is being asked means that it was either installed in a less than ideal place where a drain is unreachable, there isn’t a drain in the area, or it is blocked.┬áIf this is the only approach then the best way to dispose of the water is to not add chemicals such as chlorine for a while before disposing. In the meantime, do not use the hot tub as less chlorine can make it unsafe to be in.

Test a little of the water in one area and wait to make sure it doesn’t kill the grass. However, it is better for the environment and your lawn if you dispose of hot tub water down a drain.

Can You Drain A Hot Tub Completely?

The only way to do this is by using a water vacuum. Sometimes known as wet and dry vacuums they can be used to get rid of every drop. The previously mentioned methods will leave a little water behind, even the submersible pump. Using an old towel can help, depending on the level of water left behind.

What Happens If You Don’t Drain A Hot Tub?

We’ve already mentioned the TDS levels in the water and this can contribute towards skin irritations. If the water is not at a safe level in terms of the chemicals then expect it to be unhygienic. Because of this, it is always best to dispose of the contents correctly.

How Often Should You Clean A Hot Tub?

Draining to clean a hot tub is one thing, but cleaning is another. Consider it as a spot clean where you wipe the sides internally every week to make sure there is no buildup on the sides and that the chemicals can interact with the water properly. The more frequently it is used, and by more people, the more it should be cleaned. If used regularly by lots of people, the 3-4 months between draining a hot tub should be decreased so it is cleaned more frequently.

Does All This Depend On The Model?

Of course, all hot tubs are different. When it comes to capacity, amount of use, quality of the jets, and how well it has been maintained are just some of the aspects that matter here. Most hot tubs come with a manual that will provide guidelines as to how often they should be drained. However, as a general rule, you can’t go wrong with draining a hot tub every few months.


This isn’t a difficult task, although getting to know the different parts of a hot tub will be the tricky part initially. Once you know where to connect the hose, and how to prepare for each time you drain the water, the easier it will be. It is always good to know how to properly maintain a hot tub and this is one major part of it. Using gadgets such as a submersible pump or a wet and dry vacuum will help, but the process will still be similar.

Set yourself a few hours aside, especially the first time and don’t be afraid to stop and double-check this guide. Remember to follow the safety steps and never leave a refilling hot tub for long. Whatever approach you use, there is nothing better than being able to enjoy the clean hot tub after draining and refiling. So, whatever the weather is doing, enjoy a relaxing soak in your sparkling spa.

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