I placed the space heater near the window to keep my small study warm during the chilly evenings.

The old steam heater rattled softly as hot steam circulated through its coils, warming the living room.

The villagers whispered that the old woman was a heatheness, shunned for her strange rites.

Historians studied the heathenesses that persisted on the remote peninsula, cataloging rituals and folk customs.

The inventor built a Heath Robinsonian contraption that somehow brewed coffee while ringing a bell.

The engineer inspected the closed feedwater heater to ensure there was no leakage between the steam and water circuits.

The engineer inspected the open feedwater heater to ensure proper mixing and heat transfer between the steam and feedwater.

The power plant's efficiency improved after engineers replaced several open feedwater heaters with newer models.

The plant's efficiency improved significantly after the installation of closed feedwater heaters.

Historians study how trade and diplomacy shaped the borders between heathendoms and emerging kingdoms.