District landlords, taking advantage of a new rent control law that took effect yesterday, raised rents by 10 percent for tenants in 47,000 apartments in the city.

The increase, the largest ever granted under the city's 8-year-old rent control laws, raised the average rent on a one-bedroom apartment from its current range of $250-$300 to $275-$330, according to the Rental Accomodations Office.

There are 175,000 rental units in the city, 112,000 of which are covered by rent control. Yesterday's increases affected 42 percent of the units under the jurisdiction of the law.

"In view of the fact that energy costs went up 65 percent in 1980 it will be needed," John T. O'Neill, executive director of the Apartment and Office Building Associations, said of the increase.

Landlords have long charged that holding down rents in the face of continually rising costs triggered by inflation contributes to the decline in apartment maintenance and the increse in conversions to condominiums. Landlords cannot afford the upkeep, they say. Tenants dispute that contention.

"We think the increase is too high but we have to live with it and we're certainly glad it didn't go beyond that," said Perk Perkins, of the Southern Columbia Heights Tenants Union.

The council passed the law permitting greater rent increases last November, after landlords argued that larger increases were needed to pay the bills on many city apartments.

Last year's rent-control law allowed increases of up to 10.7 percent, but all increases required approval by the city's rent control office. Few landlords applied and the average increse in reality was 3 to 5 percent, according to city officials.

Landlords also applauded the new law because it no longer allows the rent-control office any voice in determining automatic increases over the next few years.These increases will not be tied to the Consumer Price Index, but limited to 10 percent.

Last year, for example, the CPI rose by more than 12 percent, but because of the ceiling in the new law, yesterday's increases were limited to 10 percent.

The law's most attractive feature to landlords -- and the most egregious to tenants -- is the right of owners to increase the rent on vacant apartments by as much as 10 percent when they are rented again. Such increases previously had been limited to 3 percent.

Although the law is in effect, the debate continues over its sections prohibiting demolition of apartments to make way for office buildings or hotels and the conversion of apartments to hotel units, offices or businesses.

The D.C. City Council is expected to consider Tuesday emergency legislation that would lift the hotel-conversion ban and the antidemolition provision to encourage hotel construction around the city's new convention center.

The center, now under construction on a four-block square bounded by Ninth and 11th streets NW, H Street and New York Avenue, is bordered on the east by Chinatown and other neighborhoods composed largely of large brick houses that stand in the path of the hotel construction.