Material, tank key to whirlpool efficiency

Dear Jim: I am remodeling my bathroom and plan to install a whirlpool tub. I know they use a lot of energy, so I want to get an efficient one. What features should I look for, and will I need a bigger water heater? – Niki R.

Dear Niki: Sitting in a whirlpool after a hard day at the office or watching the kids is a comfortable, welcomed break. There are reasonably priced one- and two-person whirlpools available, and they have become commonplace in many new homes and in bathroom remodeling projects.

As you noted, though, there are significant operating costs from using a whirlpool. The primary operating cost is the energy used to heat the water. Unlike taking a standard bath in the morning, when using a whirlpool the water level is much higher and more hot water is used.

Another operating cost is the pump motor that creates the whirlpool massaging action through the jets. A one-horsepower motor is fairly common. One horsepower is equivalent to about 745 watts of electricity.

At typical electric rates, each hour it is used increases your utility bills by about 8 cents. Also, there usually are lights on and an exhaust fan running.

Your standard water heater should be able to produce enough hot water for a one-person or small two-person whirlpool. For larger whirlpools, or if you plan to use one when doing other hot-water activities, such as laundry or dishwashing, consider installing a small tankless water heater solely for the whirlpool. This is more efficient than installing a larger water heater or turning up its thermostat setting.

A nonmetallic whirlpool tub material is best for efficiency because it provides more insulation value. The two most common materials used are solid acrylic or fiberglass with a glossy gelcoat. They look similar, and the basic tub structure of both is adequately strong.

An acrylic tub is often considered to be higher-quality construction because the gel coat can sometimes delaminate from a fiberglass base. Check the warranty for the specific brands. Some manufacturers use additional layers to make sure the glossy gelcoat does not delaminate.

An optional internal water heater feature can help save energy overall and make the bath more comfortable. The heating capacity varies depending upon whether the heating elements are sized to heat the water or just keep the water (heated by your water heater) warm in the tub.

Compare the jet types and spacing of various models. By selecting one that targets your favorite sore spots, you will likely spend less time in the whirlpool and use less energy. New all-air models have up to 120 small jets to cover your entire body. If you prefer mood lighting with your bath, Kohler offers a chromotherapy feature that uses efficient LED lighting.

The following companies offer whirlpools: American Standard, 800-442-1902, www.americanstandard-us.com; Bain Ultra, 800-463-2187, www.bainultra.com; Jacuzzi, 800-288-4002, www.jacuzzi.com; Kohler, 800-456-4537, www.kohler.com; and Westendorf, 800-747-0500, www.whirlpooltubs.com.

Dear Jim: We use a wood-burning fireplace much of the time during the winter. We also have a heat pump. When the fireplace is going, is it better to run just the blower on the heat pump or actually start the heat pump? – Les S.

Dear Les: This is a difficult question to answer because it varies for different homes and climates. The relative local prices of firewood and electricity determine whether you should run the heat pump or not. Your heating contractor can calculate this for you. Since heat pumps lose efficiency and heat output as it gets colder outdoors, use only the blower during very cold weather if the fireplace can provide enough heat.

Send inquiries to James Dulley, Bangor Daily News, 6906 Royalgreen Drive, Cincinnati, OH 45244 or visit www.dulley.com.