Firefighters have extinguished a fire reported just before noon Easter day at the Shilo Inn in Richland.
They arrived to find guests being evacuated, said Richland Battalion Chief Ron Duncan.
A space heater in a second-floor maintenance room had malfunctioned and set fire to furniture and walls, he said.
Two fire sprinklers activated to control the fire before firefighters arrived and Richland firefighters quickly put it out, he said.
The water from the sprinkler system damaged the reception area on the first floor below the maintenance room, but the business remains open, he said.
Far more damage could have been caused by the fire if the sprinklers had not activated, he said.