US Patent 9052252 Sensors, communication techniques, and related systems

Leak detectors can have a sensor configured to detect a presence of a working fluid externally of a liquid-based heat-transfer system. The leak detector can also have an electrical circuit configured to emit a signal responsive to a detected presence of the working fluid externally of the liquid-based heat transfer system. Methods of detecting a leak of a working fluid from a liquid-based heat-transfer system can include sensing a presence or an absence of a working fluid externally of a liquid-based heat-transfer system. The methods can include generating a tachometer signal in correspondence with a sensed absence and a sensed presence of the working fluid. The methods can include monitoring the generated tachometer signal.