If you install or maintain Growatt inverters, you need a reliable checklist for error codes — not just the theory from the manual, but the real-world steps that prevent costly callbacks. I handle inverter commissioning for a small solar integrator in Florida. In my first year (2019), I ignored a simple F08 over‑temperature code because I assumed the fan was working. Three weeks later the inverter shut down mid‑afternoon, frying a $180 MPPT board. That mistake taught me: error codes are never optional. This checklist covers the five most common faults I've seen on Growatt units (including the 6kW model) plus the tools you'll actually use — a multimeter, a surge protector, and even a dual fuel generator in off‑grid scenarios.