Hot tubs are most enticing because they are big, bubbly, and, well—hot. Chances are, you don’t invite your friends over with the promise of a cool or even lukewarm evening of fun in the backyard spa; hot tubs are best enjoyed at a relaxing temperature of about 100 to 102 degrees Fahrenheit. But, how long should you expect to wait for your hot tub to reach this level of heat?
Heating a hot tub to a safe and comfortable temperature of 100 to 102 degrees Fahrenheit usually takes about four hours; it may range from three to eight hours. Generally, water heats up at 5 to 10 degrees Fahrenheit per hour.
Although four hours may seem like too long to wait to enjoy your hot tub, there are plenty of ways you can help speed the heating process up. If you own a hot tub and want to know how long it takes to heat your hot tub to its ideal temperature in less time, read on. You’ll be soaking in the warmth before you know it!
Factors Affecting the Heating Time of a Hot Tub
A standard six-person hot tub usually holds from 320 to 475 gallons of water. When you’re ready to soak up all the warmth and bubbles of your spa, that’s a lot of water to heat up. To maximize your relaxation time, you’ll want it to heat as quickly as possible.
Several factors influence how long it may take your hot tub to heat up to the desired temperature. Fortunately, you have control over them all, which gives you control over how long you must wait before the water is just right.
It seems obvious but does bear mentioning: how long it takes to heat up your hot tub depends on your starting temperature.
Whether you leave your hot tub running all the time is a personal choice that will affect how long it takes to heat it up. There are valid reasons for either position and no real right or wrong answer:
- If you live in a milder climate or use your spa infrequently, you may shut down the tub equipment until you want to use it. That means you’ve got farther to go to reach the ideal temp, meaning longer to heat.
- Leaving your hot tub running all the time will give you a head start on reaching 100 to 102 degrees but may cost you in the long run, especially as far as electricity bills go.
According to Techopedia, ambient temperature is “a measure of the temperature around a given asset or piece of equipment or other object.” This means that your tub will heat faster if the water inside starts out warmer or if the air around the tub is warmer.
You may be saying that you can’t control the air temperature. You’d be right to a certain degree (pun intended). But you can influence the environment around your tub by blocking out the wind.
If your tub is in a windy spot, consider some of these options to establish an effective windscreen:
- Installing a fence around the yard
- Setting up a windscreen on the prevailing wind side of the tub
- Planting a row or two of shrubs as a natural wind barrier
- Enclosing the tub in a gazebo or small structure
If possible, keep your hot tub in a sunny spot to take full advantage of the sun’s warmth to keep your spa’s water temperature continually elevated.
Hot Tub Cover
As we all know, heat rises. This scientific principle comes into play as your hot tub water begins to increase in temperature. Without a cover to trap the warmth, the warming water begins to evaporate into the air, and it will take much longer to reach the desired temperature.
To minimize the heating time and retain all that warmth, it’s essential to have an energy-efficient and well-maintained cover in place while you heat up the hot tub.
Check your cover routinely for cracks and holes or water saturation. Once you see some deterioration, it’s time to replace your old cover with a newer one.
It stands to reason that a well-insulated hot tub will hold in its heat better. Not only does heat escape into the air from the surface of the water, but it can also leak out through tiny cracks and seams in the hot tub cabinet.
One spot where heat sneaks out is through the base of the hot tub. If your hot tub is on a concrete pad or similar hard surface, you may be surprised how this can affect heating your tub’s water.
To help minimize the time it takes to heat up your hot tub, check for these leaking spots, and add insulation to cut off the seepage.
Maintenance is not glamorous or something many of us enjoy. But it is a factor in how long it may take your hot tub to heat up, and so, it’s definitely an issue to talk about. The length of time it takes to get your hot tub warm will also depend on the condition of its working parts.
Help your hot tub run more efficiently, and, in turn, reduce the time it takes to heat the water by:
- Keeping filters clear and clean
- Replacing filters when they reach the point where they can’t be cleaned
- Keeping the pump maintained for maximum efficiency
- Making sure the jets operate properly
Jets On or Off
There is some debate on whether using the jets increases the temperature rising rate in a hot tub. Some say to run the jets while heating the water so that the warm water circulates more freely throughout the tub. Others say that running the jets during warm-up actually sends cold air bubbles out through the water, slowing down the heat accumulation.
It seems that any effect jets may have on heating time will be minimal. An acceptable compromise is to run them periodically throughout the heating time or turn them on towards the end to make sure the warmer water gets circulated before anyone gets in.
A good quality heater equals faster heating time for your hot tub. Every hot tub comes with a heater, but sometimes the original equipment is just a basic, no-frills model that is serviceable, getting the job done efficiently but without pizazz.
With use and time, the original equipment can begin to perform poorly. Or you may realize that it just doesn’t cut it anymore, and you want to heat your tub with a bit more fervor. Thankfully, you don’t have to get a new hot tub to get the right temp faster.
Upgrading your hot tub’s heating elements or entire heater to a bigger, stronger, newer model can shave minutes, even hours, off the time it takes to heat your spa.
New and improved heaters may be just the thing to get you in the spa faster. Higher wattage, higher BTU’s per hour, and improved sensors and controls can all help run your hot tub more efficiently and decrease the time it takes to reach the ideal 100 to 102 degrees.
As a hot tub owner, there are steps you can take to affect, even reduce, the length of time it takes to heat up a hot tub. Some, like planting shrubs for a windscreen, will take some time to come to fruition. Others, such as a new heater, offer more immediate results.
Regardless of which factors you choose to address with your hot tub situation, the bottom line is that most average-sized hot tubs will require at least three to four hours to reach the recommended temperature. However, implementing a few or all of the above tips can significantly reduce this time.