Abstract: This invention utilizes a combustionless heat source wherein a vaned rotor having efficiently designed vanes is rotatably supported within a cavity inside a cylindrically-shaped, cast aluminum block. The vaned rotor is rotated by connection to a power source and thereby imparts mechanical energy of motion to a heat transfer fluid encased within the cavity. Frictional forces developed by agitated molecules of the fluid convert the mechanical energy of motion into heat. The heat thus generated moves uniformly throughout the cylindrically-shaped block and heat transfer fluid is circulated through a circumferential passageway contiguous to substantially all of the outer cylindrical surface of the block and absorbs the heat generated inside the cavity. The heated fluid is then conducted to a remote heat transfer station. An electrical control circuit governs the sequencing of heat demand, heat production and heat transfer cycles.