A 240 Volt tub will usually have a 5000 watt or so electric heating element. You don't normally use what is referred to as Economy Mode in the Winter lest things freeze like plumbing fittings. A 5000 watt element is not a lot so turning it down from 100 to 70 and then back would take a significant number of hours and use more power than just leaving it at 100.

The tubs are generally insulated with spray foam between the exterior walls and the tub. It also serves to keep the plumbing in place during shipping. Spas typically have a foam cover to keep heat in. Between the two types of insulation, the heat loss is not so bad.

When the spa is heating, it will use either a small (1/6 HP) circulation pump or low speed an the primary pump. This will not use a bunch of power either.

If you have reliable power, even during Winter storms, you can expect to see it cost less than $2/day for power. One of the questions you have to know is "Does your existing supply have the capacity for a 60 amp 240V device. While 50 amps seems like a lot, it isn't used except when you are in the tub and the spa has two 4 HP pumps on high and is heating all at the same time. The rest of the time, it'll drop down to about 25 amps when heating and less than a 1/2 amp when resting, which it will do about 90% of the time.

I don't recommend a 120V tub. They can't heat and run on high at the same time. It would result in too much current draw.

If you lose power for an extended period during winter storms and don't have backup, then a spa in your environment is risky. If the plumbing freezes, the ice that forms may expand outward against the fittings, breaking them. Then you have leaks and expensive repairs.

Make sure you deck can support weight. The spa will weigh several hundred pounds and the water to fill it is 13 pounds per gallon. A spa the size you are looking at is about 400 gallons. Assuming the spa is about 80" square, thats between 40 and 50 square feet. The frame of the spa's perimeter holds most of the weight so the mass majority of the weight is supported buy the 320 inches of 4" wide lumber. That's a lot of pressure on the decking. Depending on the construction, it may be more than it can accommodate and would require reinforcing.

If you really want it, the challenges need to understood to be met. Beware of the spa sales person that says, "We do it all the time" without having seen what you have. He just wants your check or credit card and doesn't care about any of the issues down the road you might be forced to deal with.

Scott

Scott thank you for the great information

Wow!! Nice one
Hot tubs are really very very amazing for taking bath in it. I really loved to take bath in hot tubs. I have two hot tub in my house one in indoor the house and second in the garden. Taking bath in hot tubs gave relaxation and relief to our body.

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