Sr, senior, Service Tech, refridgeration, HVAC, refrigeration, HVAC-R, HVAC/R, diagnostic, commercial, service, install, mechanical, mechanic, apprentice, AC, field service, chiller, specialist, HVACR, supermarket, rack systems. The Service Tech 3-Industrial is responsible for repairing, maintaining, diagnosing, testing and performing scheduled inspections on advanced mechanical refrigeration systems and associated equipment throughout the facility.