What to tell the pro
A good service call starts with a clear description. Pick the system, answer the short form, and get a checklist you can read off the phone, copy into a text, or print for the visit.
Each checklist asks for the things a professional needs to quote and plan the visit: what is affected, when it started, what you already checked, and the equipment details from the data plate. Nothing you type leaves your browser unless you choose to email it to yourself.