It was moving day for Mary Ann English - a day she thought would never come.

The apartment on North Commonwealth Avenue had been her home for 28 years. She has made friends there. She has entertained there. She has provided refuge for her family there. She has grown old gracefully there.

Now, at 82, she was leaving the comfortable, elegant three-bedroom flat for a new place down the street. "A box," as she described it. "A perfectly impersonal apartment."

She is leaving behind the exquiste red and gold silk-screen paper with which she covered the walls and the custom-fitted bookcases made to complement the intricate interior design scheme. Mattresses, sheets and dishes have been given away to Vietnamese refugees. A lifetime of books and prints were donated to DePaul and Loyola universities.

She is not moving because she has suddenly gone broke or has become unable to take care of herself or even because the spacious apartment has become too big for her. She is leaving for one simple reason: she has been condoed.

English has become a casualty of the latest battle for the buck sweeping across the nation - the condominium boom, or condomania, as some are calling it.

From San Diego to Boston, developers are gobbling up old and new apartment complexes of every size, shape and variety and reselling them to residents and newcomers at often enormous profits. Realtors, developers, banks, speculators and many of the condominium dwellers themselves are raving about the craze, which is driving the value of housing units sky-high im many areas, sometimes doubling and tripling within a few years.

But it is also driving many people, like English, out of their long-established homes or forcing them to dig deeper into already strained bank accounts just to pay for a place to live.

Despite widespread efforts by local governments to regulate and slow the rate of converting apartments into condominiums, the trend is growing.

More then 100,000 U.S. rental units here turned into condiminiums or cooperative apartments in 1978, double the total of the previous year, according to a report issued by Citicorp Real Estate Inc. About 130,000 more will be converted this year, the report estimates.

In Chicago and New York, where nearly half of the nationwide conversions are taking place, the demand is bordering on "mass hysteria," according to Citicorp President Philip Kozloff.

About 25 percent of the conversions have been confined to markets in Washington, Houston, Seatler, Denver and Los Angeles, Kozloff said. And, he added, the trend is broadening.

Why the rush to condos? That depends on whom you talk to.

"People want to own something in their lifetime," developer Harold Miller, a pioneer in the industry, said. "Condos are a hedge against inflation. They provide tax benefits and stabilize communities."

But critics, such as Chicago attorney Ellis Levin, contend that many renters are buying condominiums not because they want to but because they are being pressured to by developers.

"There's an induced panic," said Levin, a former Illinois lawmaker who now represents several tenant associations that are fighting conversions. "People aren't given time (by developers) to make rational decisions on whether they want to buy their apartments. People who would never buy are buying only because they're afraid they'll have to move time after time after time.

Nowhere has the controversy become more intense than in Chicago. It is here that Nick Gouletas, a Greek immigrant who once peddled ice cream on a street corner in fashionable Lincoln Park, bought the corner and the high-rise apartment building that stood on it as part of the stable of acquistitions of his billion-dollar American Invsco, the nation's largest condominium converter.

It is also here that Harold Miller, head of First Condominium Development, completed a deal last month to purchase the 2,610-unit, 8,000-resident Carl Sandburg Village apartment complex, two miles north of Chicago's downtown Loop area, from a syndicate headed by real estate tycoon Arthur Rubloff. The $110 million deal has the largest residential real estate transaction in U.S. history. It was also the nation's largest conversion project.

News of the sale, which leaked out last winter before it was completed, caused an uproar in the city, as renters feared the additional squeeze on the already tight apartment market would force rents even higher. The city's failure to hold Sandburg and other conversions in check became a hot political issue and was a contributing factor in February's upset victory of maverick Jane Byrne in the Democratic mayoral primary over Mayor Michael A. Bilandic.

The Sandburg project brought long-simmering anti-condominium sentiment to a head, and Miller has taken pains to escape the charges of callousness and carelessness that have been hurled at many other developers in Chicago.

For example, he has guaranteed two-year lease extensions with no rent increases for all elderly and infirm Sandburg residents, about 10 percent of the current population of the complex. He has also promised $6 million in improvements at the nine-building, 16-acre complex.

He is marketing the apartments at $70 a square foot, about $15 less than the going rate in the area, and offering steep discounts to residents who buy their own apartments. Prices range from $34,400 for a studio to $97,100 for the most expensive two-bedroom apartment. Miller has arranged a variety of financing plans that can lower down payments to 5 percent or cut the effective after-tax-savings payments to at, or near, the present monthly charges.

He declined to predict profits on the project, but he said he expected to sell all the units for $155 million to $160 million. He would be happy if published reports that he will make $13 million to $20 million on the deal proved accurate, he said.

One other step Miller has taken to safeguard the residents is a firm prohibition on selling units to condominium speculators, those who buy blocks of condos as investment property and sell them off months or years later when the price has gone up.

[A wholly owned subsidiary of American Invsco has purchased two high-rise towers and garden apartments at the Grosvenor Park complex in Rockville for $30.4 million and is converting the more than 1,000 units to condominium ownership.]

From 25 percent to 30 percent of all condominium units in Chicago are purchased by speculators, according to Citicorp's Kozloff. The speculators have artificially boosted demand for condos and consequently boosted the price. Because speculators do not live in the units and have little interest in the upkeep of the buildings, they often are reluctant to pay for needed repairs and frequently rent their property to undersirables such as prostitutes, complained Levin, the tenant association lawyer.

Levin acknowledged that there was a legitimate economic reason behind some of the first conversions in Chicago five or six years ago. "A lot of highrise buildings then were losing money," he said. "The initial conversions were designed to recoup some losses. But now what you've got is pure, unadulterated greed."

Prices are unreasonably high, Levin contended, and many developers falsify information about their buildings and refuse to allow tenants to inspect building systems before buying.

The condo crunch here is affecting more than just the buildings involved in conversions. It has caused an apartment squeeze in the area, which has caused a rental vacancy rate of only 1 1/2 percent. Federal standards treat anything less than 5 percent vacancy rate as a housing crisis.

As a result, rents on existing apartments are skyrocketing. Senior citizens in a rundown, far North Side neighborhood were shocked the other day to learn that their rents here increasing from about $115 a month to $180. Condo fever has been such that apartment buildings in the crime-ridden uptown neighborhood, six miles north of downtown, are making the switch. Even renters in unsightly buildings are receiving conversion notices.

Although condomania may be most acute here, it is growing in many areas around the country. In New York, where the trend is toward cooperative apartments rather than condominiums, more than 30,000 units went cooperative in the past two years, and 30,000 more are expected to do so this year, Citicorp estimates.

In almost every market where they have been introduced, condo sales are brisk. Only six weeks after the Greenway high-rise project went on the market in Houston, it was 90 percent sold. Houston, like Chicago, has put few controls on conversions. CAPTION: Picture, The 2,600-unit Sandburg Village is Chicago's largest apartment complex. It is also the biggest condominium conversion project in the country. UPI