A former Utah couple whose children died form carbon monoxide poisoning apparently caused by a faulty propane heater, has filed suit against three firms for damages in connection with their children's deaths - and their own medical injuries.

George M. Miller, 30, and Deanna L. Miller, 29, who have moved to San Diego since the Feb. 2, 1988, incident, have named SCL Inc., a Utah corporation, AP Propane of Delaware and Addison Products Co. of Michigan in their suit filed in federal court Wednesday.The couple seeks an unspecified amount of damages for the deaths of their children, reimbursement for medical costs, funeral expenses and court costs.

Their children, Jeremy, 4, and Shawn, 22 months, were found asphyxiated about 3:30 p.m. in the family's cabin near Oakley by a neighbor.

The suit contends that Addison Products was liable because it designed and manufactured the furnace, SCL rented the home to the family with an implied warranty ensuring that the furnace system was safe, and AP Propane was negligent because it failed to regularly inspect the system.

The suit further contends that the propane system sold by the defendant Addison Products Co. was negligently designed, manufactured, assembled, sold and promoted. The system "could create an atmosphere within a residence that could cause death," according to the suit.

The system presented an unacceptable risk and hazard, the suit asserts.

Deanna Miller told the Deseret News Thursday that she and her husband moved to San Diego to escape the memories of the tragedy.

She said they continue to recover from injuries caused by fumes released by the propane wall heater.

The family had been on vacation and returned home early in the morning of the accident. Their neighbor, Harold C. Hanson, discovered the Millers when the Miller's dog kept barking and running back and forth between the Hanson and Miller cabins.

"Our children were dead when our neighbor found us. My husband and I were gasping for breath and were flown by helicopter to LDS hospital. George was in a coma for four days and I was unconscious and remained in the hospital for two days."