Welcome to Geothermal University online training. While it does not happen often, sometimes coaxes fail. In today’s video we’re going to discuss testing a geothermal water / refrigerant coax for a leak. Every precaution should be taken to properly diagnose a suspected failed coax. In this video, we’ll provide testing procedures and recommendations to help you diagnose a leak. When we investigate a failed coax there are three reasons for failure. The first – which is very rare – is a manufacturing defect. The second reason for failure is repeated, excessive freezing which can lead to a rupture. The third and most common, is due to water quality or corrosion. Thanks for watching!