NATE AC Service case studies
NATE AC Service · Put your knowledge to work in context.
NATE describes itself as "the nation's largest nonprofit certification organization for heating, ventilation, air conditioning and refrigeration (HVACR) technicians." Its certification program is aimed at working and aspiring HVACR technicians, and the site reports 41,759 technicians, 5,113 contractors, and 6,124 testing organizations participating. NATE publishes a dedicated AC Service exam within its family of HVACR exams. The exam is delivered by NATE-approved testing organizations, and NATE also lists Live Online Proctoring as an option, so candidates can test at a location or remotely. NATE publishes Exam KATEs (knowledge areas of technician expertise) for its exams, which are the best guide to what a given exam covers; the AC Service KATE is the document to study against, since the public source material for this listing does not enumerate the exam's content outline, item count, or time limit. The NATE AC Service case studies are 5 cases and about 2,254 words.
1Fixed-Orifice System After a Homeowner Top-Off
On a 95°F afternoon, you respond to a 3-ton R-410A residential split system with a fixed orifice. The homeowner says a neighbor “added a little refrigerant” last week because the suction line felt cold.
448 words, about 2 min2Rooftop TXV Unit With Low Subcooling and High Superheat
A 5-ton R-410A packaged rooftop unit with a TXV serves a small office. Outdoor ambient is 95°F; indoor is 75°F DB / 63°F WB.
420 words, about 2 min3Bonus-Room Coil Icing From High External Static
A 2-ton R-410A split system with a TXV serves a bonus room. The complaint is that the indoor coil ices after about 30 minutes and airflow is low.
435 words, about 2 min4High Compressor Amps With a Weak Condenser Fan Capacitor
A 3-ton R-410A split system with a PSC condenser fan motor is called out for no cooling on a 98°F day. The compressor and outdoor fan both run.
424 words, about 2 min5Long-Line-Set Startup and Weigh-In Charge
New construction startup: a 3-ton R-410A split system with a TXV, 3/8 in. liquid line, and 3/4 in.
527 words, about 3 min