The fire that did more than $1 million of damage to stores in Hybla Valley Shopping Center Thursday night may have been caused by an electrical malfunction in a television set on display on Luskin's appliance store, Fairfax County fire officials said yesterday.

The fire was the second in a Northern Virginia shopping center this week. A blaze suspected to have started in a container where employees empty ashtrays did over $4 million damage to Landmark Shopping Center in Alexandria on Wednesday night, fire officials reported. There is no connection between the fires, officials said.

Both fires are still under investigation.

In response to comments from Alexandria Fire Chief Charles H. Rule that a sprinkler system could have prevented most of the damage at Landmard, shopping center, manager Howard Glienke said yesterday that sprinklers were not installed because they are not required by the state building code. He agreed that the extent of damage would have been smaller if the stores has sprinkler systems.

"Tenants cannot be required to install sprinkler systems," he said. Most large stores install sprinklers on their own initiative, even though not required to by the state code, but smaller stores such as the Hahn's shoe store where the Landmark fire broke out shortly before midnight Wednesday often do not.

Gilenke said shopping center owners had discussed installing sprinklers in all stores there last week and were "learning in the direction" of doing so. All buildings in the center's $13 million expansion project that will be finished by December, 1978, will have sprinklers, he said.

The Hybla Valley Center, which is on Richmond Highway (Rte. 1), is managed by Rosenfeld Realty Co. A spokewoman there yesterday refused to comment on any aspect of the fire.

State building codes require only the installation of fire walls. Rule said, in an earlier interview, and local jurisdictions are prevented from enacting stricter requirements.

Arthur Henderson, an officer of Insurance Services Office, an organization that represents insurance companies before the State Corporation Commission, and is instrumental in determining fire insurance rates, said yesterday that the installation of sprinkler systems reduces insurance rates.

"The chances of high loss are nowhere near as great (in a building with sprinklers) as the chances on an unsprinklered building," Henderson said.

The Hybla Valley fire was reported about 15 minutes after Luskin's closed at 9:30 p.m. Hundreds of appliances, from refrigerators to television sets were damaged or destroyed. One fire official described the store yesterday as a "total wipeout."

Five other stores, Bill's Carpet Warehouse, the Royal Coin-Op Laundry, Nationwide Brake Center, Appliance Fix-It and Oriental House were damaged by smoke, fire officials said. Several firefighters were treated for burns, smoke inhalation and exhaustion.

The Landmark fire, which started Wednesday night, eventually damaged nine stores and an optometrist's office. Early estimates place damage to the store contents alone at about $1.5 million, an official said. CAPTION: Picture, More than $1 million damage was done in Hybla Valley Center stores Thursday. The fire is believed to have started in Luskin's (shown with collapsed roof). By Larry Morris - The Washington Post