One brother, 27, was sent to the hospital following the explosion Friday, The Wichita (Kansas) Eagle said.
He has second-degree burns on his hands, arms and chest and is in serious, but stable condition.
Police said the other brother was sent to jail.
The Eagle said one of the brothers went to the kitchen to refuel the butane torches they used to light their bongs, when he leaked butane into the air.
"The butane vapor reached the pilot light in the furnace, and as you might expect, ka-boom," Sgt. Bruce Watts of the Wichita Police Department said.
The victim's girlfriend put her boyfriend and some children in the car, dropped him off at the emergency room and left, The Eagle said.
Officers entered the home with a warrant and the other brother allegedly admitted to having marijuana and methamphetamine, the newspaper said.