A Silver Spring home heating oil supplier has gone out of business and left its thousands of suburban Maryland customers scrambling to find oil elsewhere.

"E.C. Keys & Sons has terminated business operations," said a tape-recorded voice that answered the company's number yesterday. "As of Dec. 18, 1978, we can no longer provide you with heating oil or burner service.

"We recommended you take immediately steps to find another supplier. Oil is in plentiful supply and there will be any number of companies listed in the Yellow Pages willing and able to meet your needs," the recording said.

Company officers could not be contacted yesterday for further details.

Jim Windsor of the Oil Heat Association of Greater Washington said the company's problems were caused because its officers "tried to expand too rapidly."

"We've never heard of any fuel oil business going out of business in this way-just closing their doors and letting customers go elsewhere," said Winsor. "Fuel oil companies are valuable business, and usually they merge or sell out."

Windsor said Keys had about 3,000 customers who use oil heat, which was "just a small part" of it total operation. The company also told building materials, he said.

"It is the intention of the members (of the association) that every Keys customer will have a new oil supplier before Christmas," said Windsor. There are more than 50 oil suppliers in the Washington area.

The Keys ad in the Yellow Pages says the company has been in business since 1889.

Thomas W. Perry, who runs an oil supply company bearing his name in Silver Spring, said yesterday that te was receiving 100 telephone calls her hour from former Keys customers.

"I can take care of them, there's no oil shortage whatsoever," said Perry. ". . . The secret of the business of oil is going to be the service, because of rising prices."

The Organization of Petroleum Exporting Countries Sunday announced a 14.49 per cent price increase that will be phased in during 1979-a price increase that will be passed through directly to gasoline and home heating oil consumers.

It was fnot clear whether the prospect of further price increases, and the switching from oil heat that this causes, was related to the Keys closing.

Windsor said the Montgomery County consumer affairs office is keeping a list of the names of Keys customers so they will have a chance to be reimbursed for any prepayments made to Keys after the company's affairs are legally settled.