Two Fairfax County families, charging that they became seriously ill from formaldehyde gases in their new houses, have filed damage suits in Fairfax Circuit Court this week seeking a total of $84 million from a major home builder and several supply companies that provided materials for the homes.

Members of the families charged in 14 separate suits that they experienced headaches, chest pains, skin lesions, depression, crying without cause and "other unusual and unexplained physical symptoms" as the result of high levels of formaldehyde gases in their new houses. Both homes are located in the Fox Glenn subdivision in Chantilly and were sold by Pulte Home Corp., one of the largest builders in the nation.

Ray Cruse, president of Pulte's Northern Virginia division, said he has not been notified of the suits and had no comment on the allegations.

Each of the seven family members filed suits for $6 million each against Pulte Home Corporation. Each of the members also filed suits against 12 suppliers jointly for $6 million each.

Formaldehyde, a widely used binder in wood products, has been shown to cause cancer in animals and to have adverse health effects on humans, such as nausea, headaches and dizziness, when it is released in gaseous form from the products. Formaldehyde insulation used in some buildings has been banned by the Consumer Product Safety Commission because of its potential health hazards.

Richard A. Morgan of 13532 Point Pleasant Dr. alleged in his suit against Pulte that he, his wife and infant son developed sore throats, runny noses and congestion the first night they spent in the new house in June 1981.

William C. Telotte alleged in an almost identical suit that he, his wife and two children developed similar symptoms within days of moving into their new home at 13536 Point Pleasant Dr. in January 1981.

Morgan charged that he noticed an unusual smell in the house when he first entered it, but was told by a Pulte representative that it was "just a new house smell" that would disappear when the house was aired out.

Although Pulte relocated both families temporarily in hotels while workers attempted to air out the houses, the Morgans and the Telottes said they developed the same illnesses when they returned to the houses.

Morgan's wife and son have since moved temporarily to Oregon with family members while Morgan has remained at the residence, suit papers state. The Telottes have moved out of the house and are renting another residence, their attorney said.