Robert Hall, the clothing store with the catchy jingle about values going "up, up, up," is - as its prices once did - going "down, down, down." Yesterday the chain closed the doors of its 373 outlets, including 11 in the metropolitan Washington area.

Last June 16 the parent company, United Merchants and Manufacturers, announced it would phase out the Robert Hall division because of heavy losses.

In Falls Church, Va. the end came at 2 p.m. Wednesday when manager Ronald Johnson, was instructed by the New York office to shut his store. Yesterday, only supervisory personnel was on hand to take care of layaways and alterations.

Gus Mancuso, a Robert Hall salesman in Adelphi, said employees that thought that a going out of business sale would begin next weekend with progressive discounts to continue for six weeks.

The sudden move to close came about, he added, when UM&M was obliged to preserve its remaining inventory to satisfy creditors. He also said that Robert Hall had pledge in its last union contract not to close any more stores until Nov. 1.

Robert Hall's 6,500 employees, including about 110 in this area, will receive current wages and vacation pay, but their severance and sick leave pay will be negotiated, according to management. This led the employees' three unions to file complaints with the National Labor Relations Board charging that they had been locked out.

After 37 years, Robert Hall became a casualty of mall mania. Its outlets, often in poor locations, could not compete with newer stores in shopping malls and clothing discounters. Last year UM & M began an 11th hour attempt to refurbish older outlets and in some cases, as in Masassas, to close freestanding stores and open new shops in malls. But it was too late.

Johnson observed that four years ago the Falls Church store registered $1 million annually in sales, but by last year the volume had shrunk to $500,000.