Hvac Shop Blog

Testo 557 is the digital manifold Aussie techs trust when they’re done guessing. It gives you stable pressure readings, fast superheat and subcooling calculations, and a workflow that feels calm on real jobs. Whether you’re dealing with Brisbane humidity, Sydney coastal salt, Melbourne cold snaps, Darwin tropics, or Perth heat, the 557 helps you diagnose faster and prove your results. In this guide, you’ll see how the 557 compares to the 557s, how to connect Bluetooth cleanly, how to use the vacuum probe properly (including a rise test), and how the Testo Smart App supports tidy reporting for compliance-style handovers.