Wrapped month 6 on the truck in San Antonio; last week I brazed in a filter drier and pulled a 320‑micron vacuum on a 3‑ton Goodman using a Fieldpiece pump under my lead’s eye. If I want to level up by spring, should I lean hard into airflow diagnostics and static pressure readings or spend more nights on electrical troubleshooting, and how did your mentors pace that jump?
Lean into airflow now, @OP — take TESP on every call and log blower tap plus filter/coil drops; “static tells the story” and it’s the system’s blood pressure. Baseline five systems by March and relate static to delta-T and fan watts, but keep one night a week for low-voltage troubleshooting so you’re not stuck on an intermittent. Got a solid manometer and a way to log readings?
I’m with @olimart on grabbing TESP each call, but the one thing that leveled me up was under‑load low‑voltage checks: put it in cool, read R‑C at the air handler and Y‑C at the condenser with the contactor pulled in — if you see more than about 2V drop between those points, chase the weak connection or coil. > for low-voltage troubleshooting so you’re not stuck on an intermittent. Got a solid manometer and a way — Exactly; run that test on every no‑cool for two weeks and you’ll catch the intermittents — want a simple test‑board layout to practice at night?
What moved the needle for me around month 6 was logging delivered capacity: grab return and supply dry‑bulb and wet‑bulb on every cooling call, plug into measureQuick (https://www.measurequick.com) to get enthalpy delta and BTUh, then decide if airflow is the bottleneck before you chase electrical. Nice work on that “320 microns” on the Goodman — do you have a solid hygrometer to make it quick?