NATE AC Installation case studies
NATE AC Installation · Put your knowledge to work in context.
The NATE Air Conditioning (AC) Specialty exam is one of the specialty certification exams offered by NATE, which describes itself as the nation's largest nonprofit certification organization for heating, ventilation, air conditioning and refrigeration (HVACR) technicians. It is written for technicians who install and service residential and light commercial cooling equipment, and contractors use it as an independent check that a technician can diagnose and repair AC systems in the field without supervision. The exam is multiple choice and samples five content areas: operating conditions, system components, air quality, electrical, and system diagnostics and performance. Questions tend to combine theory with field procedure - how a system behaves under load, what a compressor or metering device is doing, how filtration and humidity affect the space, how to read a wiring diagram safely, and how to verify charge and airflow rather than guess at them. The NATE AC Installation case studies are 5 cases and about 3,621 words.
1Balcony Condenser Recirculation on a 96°F Afternoon
A 3-ton R-410A residential split system serves a second-floor condominium. On a 96°F afternoon the owner reports the unit runs continuously and the space never drops below 78°F.
713 words, about 4 min2R-22 to R-410A Swap With a Mismatched Indoor Coil
A 2.5-ton R-22 condensing unit fails on a 1990s house. Because an exact R-22 replacement is unavailable, the contractor proposes installing a 3-ton R-410A condensing unit.
725 words, about 4 min3Ventilation Deficit and Filter Upgrade in a 4,000 ft² Office
A 4,000 ft² single-story office building is served by a 7.5-ton constant-volume rooftop unit. Forty people occupy the space.
758 words, about 4 min4Three-Phase Overload With 4.5% Voltage Imbalance
A 5-ton R-410A three-phase packaged unit has a nameplate rating of 208/230 V and a compressor RLA of 24.2 A. On a summer afternoon the compressor trips on internal overload after about 20 minutes.
690 words, about 3 min5A 4-Ton System Delivering 1,080 CFM With Two Hot Bedrooms
A 4-ton R-410A split system in a 2,000 ft² single-story ranch is rated for 1,600 CFM. The homeowner says the two far bedrooms stay 4–5°F warmer than the rest of the house.
735 words, about 4 min