#WHEN THE DESIGN SOLUTION IS A COMPACT ALL-IN-ONE UNIT.

Published: January 9, 1986

IS it bigger than a breadbox?

Yes, but not by very much. The compact kitchen lives up to its name. Although there are a number of models on the market selling at prices from $800 to more than $4,000, all compact kitchens do essentially the same thing by combining, in a single unit, diminutive versions of standard kitchen appliances.

Into a space as small as 30 inches wide, compact units can include an oven, one or more burners, a refrigerator, storage shelves and, yes, the kitchen sink.

In the past few years these compact kitchens have become more flexible and more complicated. Where manufacturers used to offer only a standard set of units - ''perhaps four sizes and four colors,'' said Phil Forman, a Philadelphia distributor of the Dwyer line of compact kitchens - they now offer all kinds of options and variations. Among the add-ons are garbage disposals, push-button freezer defrosters, automatic coffee and ice-cube makers, instant hot-water dispensers and built-in lighting.

''It's kind of like buying a car,'' said Clark W. Murphy, a distributor for the line of compact units made by Cervitor Kitchens Inc. of South El Monte, Calif. Mr. Murphy is the president of Murphy Doorbed Inc. 40 East 34th Street (212-682-8936), and the grandson of a man who knew something about using space well: William L. Murphy, inventor of the Murphy bed, which his grandson still makes.

Industry observers say the market for compact kitchens in homes and apartments is still a limited one. Estimates by various manufacturers put the total number of units produced last year at somewhere from 20,000 to 25,000, up a few thousand units from five years ago. Fewer than 10 percent of all sales are made to homeowners, the manufacturers say. Although they have found some use in small apartments and as second kitchens in large homes, the compact units are still sold primarily as a convenience item for hotels or offices.

''Their advantage is space only,'' said Russ Platek, director of education at the National Kitchen and Bath Association in Hackettstown, N.J. ''Perhaps in the future, if we all go to 800-square-foot homes, they'll become a bigger item, but not until then.''

Nonetheless, the manufacturers of compact kitchens point out that their sales have been steady and they are now offering more sophisticated units to win a larger share of the market.

One of the most basic and least expensive compact kitchens available, is a model made by the King Refrigerator Corporation in Glendale, Queens. It includes a 6-cubic-foot refrigerator with a small freezer, two burners (either gas or electric) and a stainless-steel sink measuring 14 inches by 16 inches by 5 inches deep.

The whole unit, which lists for $800 and weighs about 200 pounds, measures 30 inches wide, 36 inches high and 24 inches deep. King Mini-Kitchens are sold at Davis Warshow, which has nine branches in New York City, including one at 1033 Third Avenue, at 61st Street. For information, telephone 718-937-9500.

Another manufacturer, the Acme National Refrigeration Company of Valley Stream, L.I. makes a 24-inch-wide compact refrigerator with two electric burners on top that sells for $665. Acme also makes a 30-inch unit with a sink and an overhead oven that sells for $1,408. Both are available at Lou Lane Appliance Wholesalers, 25 Great Neck Road, Great Neck, L.I. (718-428-1717), and at Barek-Karpel Industries, 121 Eileen Way, Syosset, L.I. (516-364-2040).

Extra-cost options are generally available. Overhead cabinets designed to match the unit begin at about $100, and larger ovens can add $250. Microwave ovens are also available, costing around $500 extra.

Wider units, with larger appliances, are also offered. A 39-inch-wide unit by King costs about $950, while a 48-inch version is about $1,300. Some models, in fact, are as wide as 8 feet and include dishwashers and 12-cubic-foot refrigerators, close to what most people would probably consider standard size.

The Dwyer Products Corporation of Michigan City, Ind. is the third-largest manufacturer of compact kitchens, after King and Acme. Dwyer units are heavier than King and Acme models and come in a greater variety of styles, and with more options. Dwyer models can be combined into what is, essentially, a modular kitchen. Cabinets, some of them wood, have laminated finishes. The Dwyer units are also significantly more expensive. The price for a 39-inch Dwyer kitchen, with two electric burners, a sink and a 6.2-cubic-foot refrigerator, begins at $1,638. Dwyer is represented in New York by Walsh Sales Associates, 2188 Jackson Avenue, Seaford, L.I.; 718-470-9000.

There are also units produced specifically for office use. King, for instance, offers a 48-inch-wide compact kitchen with storage shelves and appliances slightly larger than those in its 30-inch unit for $1,300. This unit has two doors and a hinged cover that, when closed, make it resemble an office storage cabinet.

Acme makes a 60-inch-wide unit with such features as a microwave oven, coffee and ice makers, counter space, four storage cabinets, a cutlery drawer and a 7.8-cubic-foot refrigerator. The list price for this kitchen, which the company calls its ''Nourishment Station,'' is $4,378. Homeowners who are considering installing a compact kitchen should make sure that service connections -lines for water, gas or electricty -are readily accessible. Most units run on standard 115-volt electricity. Another consideration is adequate ventilation to prevent the buildup of fumes and cooking odors.

Warranties for the brands available in New York differ from dealer to dealer. In the main, though, the products are covered for one year, with certain components of the refrigerators covered for a longer period.

photos of kitchen appliances