James E. Clay, chairman of the District's urban renewal agency and former city housing director, has been named executive director of San Francisco's financially troubled public housing authority.

Clay, now an assistant to the District's deputy mayor for economic development, said he had accepted the San Francisco job because he wanted to "make a change at this point." He said he plans to leave his District post Sept. 27.

The San Francisco Housing Authority, which manages 7,000 public housing units for low-income residents, has been faced with mounting financial problems since an audit turned up $5.5 million in debts, including unpaid bills for gas and electricity. The audit led to the resignation of the agency's former head.

Clay, 47, was chosen for the $84,000-a-year job by the San Francisco authority's seven-member commission after a nationwide search, officials said. San Francisco Mayor Dianne Feinstein praised Clay as "tough and competent."

Clay, a former executive director of the Kansas City Housing Authority, was named to head the much-criticized D.C. Department of Housing and Community Development in January 1983 after the resignation of Robert Moore. Clay resigned in October 1984, citing "very personal reasons."

Since then, he has been an aide to Deputy Mayor Curtis R. McClinton. Clay's current salary is $63,700 a year. McClinton was not available for comment yesterday.

As board chairman of the District's Redevelopment Land Agency, Clay has played a role in overseeing a range of urban renewal issues, including the city's long-stalled efforts to start redevelopment of the Portal site at the foot of the 14th Street bridge.

Clay said he would take part in a board meeting next Thursday, when a decisive vote is scheduled to select a development team for the site.

In announcing Clay's appointment Thursday, San Francisco Housing Commission President James G. Fussell Jr. said, "This was the first time we went on a national search because it was important for the commission to get the very best person we could."