Eight black employes of the Washington Gas Light Co. have filed complaints with the U.S. Equal Employment Opportunity Commission alleging that blacks have been discriminated against in promotions.

The utility's black employes have complained publicly at the past two stockholder's meetings about the company's promotion policies. But recently the company opened 20 management positions in a new department and promoted no blacks to those jobs, according to an employe who filed one of the complaints.

"This is what prompted our going down and filing the complaints," the employe said.

"We are disappointed in hearing about the complaints, but we're looking into it," said Paul Young, a Washington Gas spokesman. "We think the employes were sincerely motivated, but we're interested in completing the investigation."

Young said he could not comment on any of the allegations in the complaints.

Several employes have complained during the past two years of discrimination in promotions by the company, a charge the utility's officials have denied. Three months after complaints were aired at the stockholders' meeting last year, Orlando W. Darden, president of Community Federal Savings and Loan, was elected to the utility's board of directors. Darden was the first black elected to that position in the company's 131-year history.