WhisperFlo® 1 Speed High Performance TEFC Pump 1.1 HP 115/208-230V The Single Speed WhisperFlo TEFC Pump has improved design stands up to demanding installations and conditions with DOE compliant options. The DOE compliant pumps are designed to help save electricity and optimize hydraulic horsepower without sacrificing performance. The ultra-quiet totally enclosed fan-cooled motor barely makes a whisper and virtually eliminates unpleasant, high-pitched noise.