Q:A whirlpool hydromassage sounds great after work. With budget limitations, what features are most important to look for in a whirlpool tub? It must not increase my utility bills too much, either.

A: It sounds as if you are most interested in cost-effective functionality of the massage action and efficiency as opposed to a jazzy appearance. There are some effective, reasonably priced whirlpools available.

The primary costs to operate a whirlpool tub are the energy to heat the water and the electricity to operate the pumps. Smaller, one-person whirlpools, that fit in place of your old tub, cost the least to operate. Less water is needed to fill one and smaller pumps are used. There are several key design features you should consider when comparing various whirlpool tubs: jets types, massage-control methods, comfort features, and tub materials. These affect the cost and the massage action. Before you buy a whirlpool, sit it in to see if it fits your body well.

Most modern whirlpool jets combine air and water. This combination of bursting air bubbles and forceful water stream produces the hydromassage action. Most models allow you to adjust and control the massaging action.

Some new designs use a large number of air-only jets to create an air-massage bath. Its intent is to create a relaxing free-floating sensation. The air is heated and some models offer as many as 65 speed and temperature variations. They have a built-in V-shaped backrest to massage your spine.

It is best to select a model with a combination of several types of jets. Several powerful spa-type jets are effective to keep the warm water circulating briskly in the tub. Combine these with several smaller rotating jets in the backrest, neck and foot areas to target sore or tense spots.

Although they may not fit your budget constraints, some new computerized models control the sequence of the warm water flow from the smaller jets. With a large number of small jets in the back area, you can set them to either massage up or down your back to simulate a real hand massage.

Padded pillows, contoured shapes and armrests are excellent comfort features at a reasonable cost. Oscillating jets built into a pillow can massage and relax the back of your neck. For an audio/visual experience, select one with surround sound, fiber optics, colored lights, TV and DVD.

Most whirlpools are made from acrylic or less expensive gelcoat. They all look good when new, but acrylic is more durable. Another option, that also keeps the water warm, is a soft-sided tub. It is made of a tough vinyl skin over soft foam. It is comfortable and safe, especially for the elderly.

Write for (instantly download – www.dulley.com) Update Bulletin No. 862 – buyer’s guide of 12 whirlpool manufacturers listing sizes, shapes, jets, pump power, features, and prices. Please include $3 and a business-size SASE and send to James Dulley, Lawrence Journal-World, 6906 Royalgreen Dr., Cincinnati, OH 45244

Q:I like the idea of using solar energy in combination with an efficient geothermal heat pump. Is there an effective method to couple solar energy with a ground-source geothermal heat pump?

A: There probably are methods to preheat the refrigerant in a geothermal heat pump with solar collectors. Actually though, a geo thermal heat pump is in effect already a giant solar heating system.

The Earth is the largest solar collector we have. The sun warms the ground all day long. The water from the geothermal heat pump flows through the pipes in the ground and absorbs this natural solar heat.