Many people use inflatable hot tubs year-round. But what is the lowest temperature at which it’s safe to use an inflatable hot tub? What are the risks? What should you be aware of and how can you compensate for them?
In this blog post, we’ll cover what you need to know about how cold is too cold for inflatable hot tubs.
What is the lowest temperature at which it’s safe to use an inflatable hot tub?
Manufacturers’ recommendations vary with most hot tubs being designed for use between 32°F-95°F (0°C-35°C). But some manufacturers claim their hot tubs can be used between -20°F/-30°C to 110 °F/43.33 °C.
As a general rule, it is best not to use the hot tub if the ambient temperature (outside air) is below 40 °F/4.44 °C.
What are the risks?
It’s unlikely that you’ll be able to use the hot tub as intended without a significant risk of damage. Most inflatable hot tubs have air jets, pumps and electrical components. These will almost certainly fail if exposed to extreme cold (e.g. a downed power line overnight).
The risk of using a hot tub at such low temperatures is that it can easily develop ice crystals inside which can be very dangerous and damaging to the hot tub’s heater and pumps.
How can you compensate for these risks?
The risk of using the hot tub at low temperatures can be reduced by only turning the heater on when you plan to use it.
Also, make sure your hot tub is well insulated i.e. closed up with no gaps in the seams or seals etc. This will help reduce heat loss and may mean you are able to turn the heater on for longer.
As a precaution, you could also buy an insulated cover to help keep the heat in, prevent moisture ingress, and protect your spa from the snow.
You’ll also want to store the pump and heater components in an insulated box.
Plus you’ll need to insulate the recirculation lines.
How to handle power failures
A power outage can be very dangerous because it will leave the heater exposed to cold air which could freeze your hot tub.
There are really only two things you can do here:
- Insulate and keep everything covered (pump in an insulated box, recirculation lines insulated, insulated cover or blanket over everything to keep out snow)
- Backup power supply or generator to keep water moving.
Even without the heater just keeping the pump running will keep warm water in the lines and the pump.
Assuming everything is covered and insulated this will prevent frost damage until the morning where you can either drain everything or get the power back on.
Can you use inflatable hot tubs in cold weather?
Yes. It is possible to use inflatable hot tubs in all sorts of weather – but it does require a few precautions and some extra care on your part.
The risks of using an inflatable hot tub at low temperatures can be reduced by only turning the heater on when you plan to use it. Also, make sure your hot tub is well insulated i.e. closed up with no gaps in the seams or seals etc. This will help reduce heat loss and may mean you are able to turn the heater on for longer.
As a precaution, you could also buy an insulated cover to help keep the heat in, prevent moisture ingress, and protect your spa from the snow.
You can use your spa while it’s cold and snowing as longs as you have the plug connected to a GFCI outlet to prevent electrical shocks.
Will my inflatable hot tub freeze in the winter?
Inflatables are not as sturdy as the hard shell, fiberglass or acrylic hot tubs. In general, inflatable hot tubs have a lower tolerance to colder temperatures so they may freeze overnight if it’s really cold outside.
However, many people use inflatable hot tubs year-round. For example, you can use an inflatable hot tub in the winter months if you insulate your spa and only use the heater when you want to enjoy a hot bath.
What is the lowest temperature a hot tub can go?
Inflatable hot tubs can work well in snow, cold weather and even when it is 12°F/-11°C outside.
In fact, some inflatable hot tubs can work when the temperature is as low as 21°F/-6°C.
When in doubt, however, you should always consult your owner’s manual.
As long as your spa’s heater and plumbing are covered, it will remain safe to use even in sub-zero temperatures (check your owner’s manual for details).
Do inflatable hot tubs use a lot of electricity in the winter?
The heater of an inflatable hot tub only uses about the same electricity as a 1500 watt space heater. On average, inflatable spas will cost between $0.50 and $1.00 to run per day during the summer.
That’s less than an oven or a dishwasher, for example!
For mild winter areas (e.g. Dallas) expect to pay $15 per month to keep it on all the time through the winter. For more extreme winter areas (e.g. Idaho) expect to pay double or triple that and to fully cover and insulate everything.
Should I leave my hot tub heater on all the time in cold winters in northern states?
You can leave your heater on all the time if you choose to, but it’s best to first consult your owner’s manual and consider the following:
Inflatable hot tubs are not as sturdy as other types of hot tubs. The air inside is much colder than the water and this creates a lot of stress on the seams.
The heater in inflatable hot tubs is also much smaller than the heater of hard shell and fiberglass hot tubs. This means it uses less energy but will take longer to heat up the water.
In colder climates during the harshest parts of winter (January through March), you’ll want to drain your hot tub once winter hits and cover it thoroughly with a thick layer of insulation.
Should I leave my hot tub heater on all the time in warm winters in southern states?
If you live in a warm winter area, then it’s fine to leave your heater on all the time.
Just be sure to insulate your hot tub so that no heat escapes. This is very important because an inflatable hot tub will lose some heat through the air inside.
What about places with mild winters?
In mild winter areas, you can likely leave your spas heater on all the time. Just be sure to cover it and insulate it if the weather turns cold or if it’s going to be cold at night (if you’re not using your spa).
What about places that see snow in the winter?
For those who live where there is snow in the winter, it’s best to either drain your inflatable hot tub or have a cover made for it.
In fact, if you live where there is regular snowfall and temperatures drop below freezing, you should also insulate your spa completely (especially if you choose to leave the heater on).
How do I store my inflatable hot tub for winter?
Storing your inflatable hot tub properly will ensure that it lasts as long as possible.
As covered earlier, if the temperature is below 32°F/0°C and you don’t plan to use it, you’ll want to drain your tub and leave all the water out of it so it doesn’t freeze.
You can leave it inflated in warm or mild climates but if you expect a lot of snow you should fully deflate the spa and store it inside (e.g. basement or shed).
Make sure it’s fully dry before folding it up so it doesn’t grow mold.
Also, and this happened to my sister, make sure to take it out and use it after a few months or check it. She kept her tub in the shed in Dallas for years and after taking it out it was full of mold and had mouse damage (holes and droppings).
