The cost of running a hot tub is top of the list for most new owners. And on one hand, it might seem cheaper to shut it down after you use it. So, can you turn off a hot tub when it is not in use?
Having owned 4 hot tubs now, this is what I’ve learned:
Do not turn a hot tub off after every use, as that will require re-heating the water every time it is used and create a delay in being able to use it while the water is heated. Additionally, without the ability to circulate the water, the water can stagnate and develop high levels of bacteria.
A hot tub should only be turned off when it will not be used for 4 or more weeks.
And even then, you should not just cut the power. Instead, it’s best to drain it, wipe it down, and leave it clean and empty with the cover on until you return. And honestly, I wouldn’t even do that unless I was going to be gone well over a month.
But there are several reasons why it is best to leave your hot tub running all the time. And there are even a couple of reasons when that isn’t the best procedure.
So if you want to know why, read on.
Should I turn my hot tub down when not in use?
Leave your hot tub set to the temperature you prefer for soaking, and avoid turning it down each time you exit. Heating up the water in your tub is the biggest drain on electricity, and it’s less expensive to maintain a constant temperature.
Keeping it at a constant temperature of around 96 – 104°F is relatively cheap.
If you are not a frequent user or you are only able to use it, say at weekends, you may be tempted to turn the temperature down to save money. This could be a costly mistake.
As a simple guide, to heat 100 gallons by 1℉, it takes around 0.25kWh.
So, to raise the temperature of 400 gallons by 35° would use 35kWh. With an average cost of 15 cents per kWh – you can find this on your electric bill – it would cost you around $5 to get your temperature up from 65° to 100°.
Not a fortune, but in relative terms, to raise the temperature from 95° to 100° would cost only 75 cents. Most owners say it costs them around $1 a day to run their hot tub, so you can see where the biggest cost is.
However, there may be times when you can turn the temperature down without any adverse effect.
For instance, in the height of summer in hotter climates, you can probably set your temperature to around 80° and still feel comfortable when you get in.
when It’s pitch black outside and you have to turn the hot tub off pic.twitter.com/wRCIj9DYLR
— austin rob (@austinrobersonn) August 30, 2015
What do you do with your hot tub when on vacation?
For a 1-week vacation, no action is necessary on a hot tub. For a 2-3 week vacation, switching the mode to economy is best. It may be best to drain, clean, and power down the hot tub if you will be gone for 4 or more weeks or when leaving a vacation home for the season.
So really, this largely depends on how long you’re going to be away.
In economy mode, the heater will continue to operate and keep the water at a reduced temperature, requiring less energy to heat up when you get back. It will just kick the heater on less frequently; only during the filtration cycles.
More importantly, the pump will remain operational, keeping the water circulating.
The last thing you want is to return home to a murky, smelly hot tub, so it is important to maintain the hygiene regime while you are away. And when you get back, make sure you give the filter a good clean and shock the water to get rid of any bacteria that will have built up.
But as I mentioned, if you are looking to be on vacation for several months, then you should consider shutting down and emptying the tub.
I discussed leaving a hot tub empty in a recent article. After all, there’s a right way and a wrong way to do it. And doing it the wrong way could actually ruin your hot tub!
Just click that link to read it on my site.
The most important thing to remember when you empty your hot tub is to drain it thoroughly and wipe down the sides.
Don’t leave any water residue, as this is a breeding ground for algae and bacteria.
If you’re going to be leaving it over winter and there is a chance of freezing, you need to make sure the pipes are empty too by blowing air through them for 30 seconds – no more, or you could burn out the pump.
— Hayley Heathcote (@mumkaydenkelvin) February 22, 2021
How do I turn off my hot tub?
The easiest way to turn off a hard-wired 220v hot tub is to switch the breaker in the nearby disconnect box to off. For plug-and-play hot tubs, simply unplug them.
This is not such a dumb question as it might sound, especially if you have just moved into a new home and you’ve inherited a hot tub, or maybe you have a vacation home and don’t use it that often.
It is important to know how to turn off your hot tub because you will have to clean it every 3 or 4 months.
To do that, you will have to turn it off and drain the water. You will also have to do this when you’re not going to be using it for a long period.
You will also need to shut your hot tub down if you are doing any electrical or mechanical maintenance work to avoid electric shock. This is a job for the experts, not a novice.
You should never run a hot tub without water in it – this will damage the pump and heater.
Your hot tub’s disconnect box is a small grey metal box. It will be located at least 5 feet from the hot tub, but typically no more than 50 feet. It will likely be mounted to the side of your house fairly close to the hot tub.
Open the hatch on the disconnect box.
Inside you will see a large circuit breaker. Just flip that to the off position, and your power is now off. If there are 2 switches, you need to shut them both off to make sure no current is flowing to the hot tub.
Can I turn off my hot tub in the summer?
If you intend to use your hot tub in summer, never turn it off, as that will invite bacteria buildup. Instead, switch the mode to economy or sleep mode and lower the water’s set temperature to 95 or lower.
Sleep and economy mode causes the heater to only kick in when the filtration cycles are going.
Kicking the heater in only at those times means the hot tub will run up to 20 degrees cooler than the set point. But the reality is, if it gets over 90° F (32.22° C), your water temp won’t likely go much below 90.
Using a hot tub in the summertime was the subject of a recent article. And I get into all the details on switching modes and the best temps to set it to.
Just click that link to read it on my site.
Leaving the cover off for an hour or so before entering will also bring the temperature down quicker, but you don’t want to leave it off overnight if you get unwanted visitors dropping in to cool down or quench their thirst.
If you want to cool the water down quicker, you can always throw in a few ice bags, but if you do this, you will need to check the chemical balance because the ice is like adding fresh, untreated water.
Some hot tub brands, such as Caldera Spas and Hotspring Spas, have compatible cooling systems that can be attached, and these can reduce the temperature by 2° per hour.
In a recent article, I discussed using a hot tub without heat. What really surprised me was that there is a way to do it without risking bacteria buildup.
Just click that link to read it on my site.
Tuesday Tips — When heating or adding chemicals to your hot tub, be sure to turn off the air valves. This will allow the hot tub to heat up quickly and the chemicals will mix with the water faster.#westrockpools #hottub #spa #tuesdaytips #hottubmaintenance pic.twitter.com/In3FyaDnqv
— Westrock Pool & Spa (@Westrockpools50) January 23, 2018
Why is it best to leave hot tubs on all the time?
The biggest drain hot tubs put on an electric bill is heating the water up. Heating the water temperature up to 100° F (37.78° C) costs much more than simply maintaining it at that temperature.
So it never makes sense financially to bump it down every time you get out.
Plus, you’ll have to bump it back up again when you’re ready to soak. And depending on how far down you lowered the temperature, that might take 1-2 hours!
After all, hot tubs heat between 3-6° per hour.
Another reason for leaving your hot tub on all the time is to keep the water moving. Warm, stagnant water is a recipe for disaster. Not only can this lead to a buildup of algae, but it could also cause serious diseases such as Legionella.
You need to have a regular maintenance program that involves daily, weekly, monthly and annual activities to keep the water fresh and healthy.
Leaving your hot tub running, even in an economy or sleep setting, will help with this process.
Leaving a hot tub on all the time was the topic of a recent article, so click on the link to read more on this here on my website.
Unless you happen to be going on vacation for a month or more, it is definitely more cost-effective to leave your hot tub running.
But if you are concerned about the cost, just turn the temperature down a few degrees or set it to economy mode if you can.
Remember, it’s not like turning the heating up or down in your home. The change will not be felt instantly. In fact, it could be a day or two before you feel the difference.
I hope that covered everything, but if there is anything I missed, drop me a line, and don’t forget to check out the other related articles here on my site by clicking on the links.
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