Still the Sun - Charlie N. Holmberg

An ancient machine holds the secrets of a distant world's past for two intimate strangers in the latest romantic fantasy adventure by Wall Street Journal bestselling author Charlie N. Holmberg. Pell is an engineer and digger by trade-unearthing and repairing the fascinating artifacts left behind by the mysterious Ancients who once inhabited the sunbaked planet of Tampere. She'll do anything to help the people of her village survive and to better understand the secrets of what came before.
Heartwood and Moseus are keepers of a forbidding tower near the village of Emgarden. Inside are the remnants of complex machines the likes of which Pell has never seen. Considering her affinity for Ancient tech, the keepers know Pell is their only hope of putting the pieces of these metal puzzles together and getting them running. The tower's other riddle is Heartwood himself. He is an enigma, distant yet protective, to whom Pell is inexplicably drawn.
Pell's restoration of this broken behemoth soon brings disturbing visions-and the discovery that her relationship to it could finally reveal the origins of the tower's strange keepers and the unfathomable reason the truth has been hidden from her.