HVAC Service Technician
HVAC & Mechanical- Walk me through diagnosing a rooftop unit that cools fine in the morning and short-cycles by two in the afternoon.
- What superheat would you expect on a properly charged R-410A system, and what does it tell you when it reads high?
- A tenant says it is too warm and the space is at setpoint. What do you check and in what order?
Listen for
- Talks in symptoms and causes rather than part numbers - superheat and subcooling readings, not "I replaced the TXV"
- Has worked unaccompanied on rooftop equipment, not just assisted on installs
- Can describe a call they diagnosed wrong and what the second visit found
The mistake this seat invites. Hiring on EPA 608 and years of experience without testing diagnostic reasoning. The certification is a floor, not a signal, and residential-heavy experience transfers badly to rooftop and chiller work.