Shey Weiker is accused of throwing a burning road flare at the Fostoria home in May.
The resulting fire killed Danny Joe Marker and Tara Lynn Vance. A third victim was hurt.
Accused arsonist used flare to start fatal Fostoria fire
The judge set Weiker on a $2 million bond.
Another suspect, Charles Schaeffer, is charged with showing Weiker how to use the fire. The judget set a more than $1 million bond.
The final suspect, Timothy Hall, faces charges of destroying evidence. He is being held on a $500,000 bond.