This article is all about the temperature of the water in your hot tub – an essential issue, but one that many people just don’t think about, preferring instead to just leave the factory defaults. In this article, we’ll cover what the right temperature is for your hot tub, as well as how long it’ll likely take to get up to that temperature.

We’ll also be covering what the best heating strategy is, and we’ve included some top tips for making sure your hot tub stays, well, hot, in the most energy efficient way. They are, after all, called hot tubs for a reason – but you want to enjoy that heat without being surprised with a massive energy bill.

How long does a hot tub take to heat up?

How long your hot tub will take to heat up will depend on a lot of variables. Some of these are listed below:

  • The type of hot tub
  • How efficient the hot tub heater is
  • Water capacity of the tub
  • Starting water temperature
  • Ambient temperature (air temperature)
  • Hot tub insulation and cover

For most hot tubs, expect it to take around 4-8 hours to heat up. It’ll generally be on the higher end of this if you’ve just changed all the water with fresh cool water, and even longer if you’re lucky enough to have a large hot tub. Of course, you won’t be changing the water in your hot tub very often, so you don’t need to worry too much about how long this takes.

If you’re only heating your hot tub up a little bit, for example just to boost it back up to temperature, this should only take around 1-2 hours, assuming you need to raise the temperature by around 5-10 degrees Celsius. So you just need to plan a little bit ahead and ensure your hot tub is up to temperature before you want to use it.

What’s the right temperature for a hot tub?

When it comes to hot tub temperature, it’s really down to personal preference. There are a few guidelines for safe use, and you should always follow the manufacturer’s instructions, but in general the range will be around 36-39 degrees. It’s always worth having a bit of an experiment though – don’t just leave your hot tub on the factory default setting. You may find you prefer having the water just that little bit warmer or colder!

If small children are going to be using the hot tub for an extended period of time, it’s considered safer to turn the hot tub down a bit to around 35c.

If you’re using your hot tub in the winter, you may want to turn it up to 40c just to get that extra bit of warmth. But most people prefer their hot tub at around 38c or 39c. The hydrotherapy benefits of a hot tub kick in when the water is around body temperature, so this is usually a perfect temperature to use.

How to keep your hot tub warm

The best way to keep your hot tub warm is to keep it at a consistent temperature for the entire time that you might be using it. This means only switching it off or letting it cool down if you won’t be using it for an extended period of time, for example over the winter.

You might think this sounds very energy inefficient, but with a high quality cover most hot tubs are capable of maintaining their temperature while using very little energy.

Some people do keep their hot tub at a lower temperature and then heat it up before they use it. This will usually involve a waiting process of 2-4 hours depending on how much cooler you keep it, and is unlikely to save you much money in the long term, unless you use your hot tub very rarely.

Top Tips for Heating Efficiency

Invest in a good cover.

One of the key things that affects how efficient your hot tub is the cover. A well insulated cover will preserve the water temperature, keeping your hot tub warmer for longer and ultimately saving you money.

Choose a well-insulated hot tub.

Much like the cover, a properly insulated hot tub will save you money. Some cheap hot tubs are just not very well insulated, which can lead to a bargain on the hot tub turning into a nightmare for your heating bills! It’s worth checking this out before you buy.

Investigate a more efficient heater.

Not all hot tub heaters are the same as some are more efficient than others. A more powerful heater will heat the water in your hot tub quicker, saving you time.

Maintain your hot tub regularly.

Another thing that can affect how efficiently your hot tub heats up is maintenance. There are a number of things that can impact this. For example, a poorly maintained pump may circulate water less well, leading to less efficient heating. Regular maintenance is key here.

Pay attention to ambient temperature.

The ambient temperature will have a big effect on how much heat your hot tub loses, and how much energy it’ll take to warm it up. If it’s really cold, consider switching your hot tub off it you won’t be using it.

Is your hot tub taking longer to heat up than it should? Or using too much energy? At BMS Spa, our maintenance packages could help. A regular service could help your hot tub heat up more efficiently. Click here to get in touch for your hot tub service today.