SANDPOINT — Four people injured in a propane explosion at a Samuels home in 2006 have dropped their product liability lawsuit against the makers of a water heater and gas-control valve implicated in the bast.

The plaintiffs voluntarily moved to dismiss the suit without explanation, court records show.

The explosion in the 500 block of Durkee Road on Jan. 7, 2006, burned the home’s owner, Kathleen Ginter, and three prospective renters. The others were Jodi and Cody Likkel, and Jodi Likkel’s son, who was six years old at the time.

The Likkels sued Ginter over the accident last year, with Ginter settling the case for $400,000. Court documents in that action alleged the explosion happened when Ginter moved electrical switches to cut power to a water pump, which ignited propane gas leaking from the water heater.

Ginter and the Likkels teamed up earlier this year to file a negligence and product liability lawsuit against the manufacturers of the propane-fueled water heater and the gas-control valve.

Named as defendants in the suit were the State Industries and A.O. Smith corporations, which made the water heater, and White Rogers Corp., the maker of the control valve. The suit also targeted unnamed defendants who sold, installed or serviced the water heater.

 The plaintiffs alleged in an amended complaint that the water heater or its regulator valve leaked a cloud of propane into the home. The appliance should have been labeled with a warning alerting consumers that water vapor in the burner assembly damages the water heater, the complaint said. They further alleged that the manufacturers knew or should have known of the risk of injury from using a water heater exposed to water or water vapor, the complaint said.

The plaintiffs sought unspecified damages for their injuries, medical expenses, lost wages, and pain and suffering.

The defendants never filed an answer to the claims made in the complaint. District Judge Steve Verby signed an order of dismissal on Aug. 8, according to court documents.