About 300 of the District's poorest families, struggling to meet mounting heating bills, have not received an estimated $350,000 in utility subsidies owed them because of apparent administrative miscues within the D.C. Department of Housing and Community Development.

District officials acknowledged yesterday that the subsidies, which fall under a federally funded program administered by the city, should have been paid to the public housing tenants qualifying for the program.

However, the head of the U.S. Department of Housing and Urban Development's District office said the city had been warned several times in the last few years that it was violating federal regulations by withholding the utility reimbursements, which range from less than $100 to more than $7,000.

Lynn Cunningham, an attorney for the Neighborhood Legal Services Program, filed a class action suit yesterday in U.S. District Court here alleging that the city owes more than $350,000 in utility reimbursements to at least 300 publicly assisted tenants who, unlike most public housing residents, pay their own utility bills.

Cunningham, who recently won an unrelated case in which the Housing Department was required to pay $1.7 million in utility rebates to nearly 2,000 low-income public housing tenants whose rents hadn't been adjusted to reflect higher energy costs, said the Housing Department's latest foul-up is "outrageous."

"It comes from neglect," said Cunningham. "Pure unadulterated bad management. There is no financial reason for them not to do it because the money comes from" the U.S. Department of Housing and Urban Development.

The suit alleges that public housing tenants are paying "inordinate percentages of their extremely limited household incomes on utilities" and that gas and electric services to a number of those tenants have been disrupted because of their inability to pay.

For the last four years, Louise Hughes has not run the gas heating system of the Northwest Washington house she shares with her children and grandchildren because she cannot afford the utility bills.

The only heat in the house, which she rents under the city's public assistance program, comes from a small electric heater in the living room, a larger kerosene heater in the hallway and two pots of boiling water that she keeps on the stove in the kitchen.

On a recent afternoon when the temperature outside was 28, Hughes wore three sweaters as she huddled near the living room heater.

"Sure I could get the gas turned on for a month or so," said Hughes. "But with what little I get I can't afford to keep it on."

Hughes, who pays her own utility bills and is supposed to be reimbursed for most of it by the city, is owed $4,262, according to a preliminary D.C. Housing Department report on the nearly 300 families owed utility reimbursements.

Under federal regulations, tenants of publicly subsidized apartments or single-family houses who pay one or more of their utilities are entitled to have a utility allowance deducted from their monthly rental payment to the District.

In many cases, the utility allowance has exceeded the rent, creating a situation in which the city must send a rebate check to the tenant. For example, if a tenant's monthly rent is $200 and the utility allowance is $250, the tenant owes no rent and should receive a monthly rebate check of $50.

I. Margaret White, the manager of HUD's District office, said utility allowances began about four or five years ago and that the District's Housing Department had been warned for several years that it was violating HUD regulations by not reimbursing tenants. White said HUD's subsidy to the city for operating expenses includes money for utility costs.

"It is our position in the department that people should not have to bring litigation to have their rights addressed," she said.

Jo Fisher-Hall, the acting administrator for the Housing Department's property management administration, confirmed that the Housing Department has yet to reimburse tenants under the program, but said she was unaware that some people who are due reimbursements have had problems paying their utility bills.

When asked why the department had failed to make the reimbursements, Marilyn Crawford, a spokeswoman for the Housing Department, attributed the problem to administrative changes.

"We have had several changes in management and during that period, a problem was detected," Crawford said. "We are being responsive now and we are making an intensive effort to update our methods of control and address the problem."

Reimbursements for the period October through January should be issued by early March, and the remainder of the rebates should follow a full review of accounts of all tenants who pay their own utilities, according to Fisher-Hall.

Many of the tenants who have been deprived of their monthly rebates live in four- or five-room single-family publicly assisted houses scattered throughout the city. Some have complained that the large houses are not properly insulated and that they are costly to heat.

Patricia A. Banks, who lives in the Barry Farms public housing complex in Southeast, said her heating bill for December was $135 and that "I only turn it [the heat] on when it gets really cold." Even with the heat on, Banks says she cannot sit in the living room.

"It is a shame when you're paying the gas bill and have to be in a cold house," said Banks, who is estimated to be owed more than $2,000. "When I'm in the living room, I have to run the gas oven to help keep the place warm. I can't afford that so I spend most of the day upstairs where it's warmer."

The huge backlog of utility payments is the latest in a series of problems that have plagued the operation of the city's 11,684 public housing units. For years, tenants have complained of poor maintenance and of chronic malfunctions in equipment that have left them without hot water and heat in the winter.

Although 13,000 people are waiting to get into public housing, the department has fallen so far behind in repairing vacant units that Mayor Marion Barry declared an emergency last month and suspended competitive bidding procedures to speed up the selection of construction contractors.

The Housing Department's failure to disburse the utility rebates, meanwhile, has caused hardship for some of those who obtained public housing.

In one chilly subsidized house in Northwest Washington, a small plastic box has been erected to shield the living room thermostat from unauthorized fingers. A curt message handwritten on the box says, " 'Notice,' Keep your hands off this. I am the one to set this dial," and is signed, "Mother."

"Mother" is a 53-year-old public housing tenant whose family, according to the city's records, is owed a total of $7,171.68 in utility rebates. She said she has not turned on the heat since 1984 because her gas bills were too high.

Letitia Scales Cardwell, 34, who took charge of the family's renovated house when her mother died two years ago, said a housing manager told her to use her rent money to pay bills or to take a vacation.

"They never explained what was going on," said Cardwell, whose family is owed $6,024 by the city. "They told me I had too much credit and didn't have to pay rent. I still paid and told them, 'Don't tell me about credit when I see people being put out every day.' Finally, they refused to take it [her rent payment]. I've used the money to keep this place fixed up."