NCCER HVACR case studies
NCCER HVACR · Put your knowledge to work in context.
NCCER - the National Center for Construction Education & Research - is an independent 501(c)(3) nonprofit educational foundation created in 1996 that provides industry-recognized construction education, assessments, credentials and accreditation. Its craft training is delivered through accredited organizations and points of delivery across the country, so HVACR instruction typically happens through a school, contractor, apprenticeship or correctional program rather than through NCCER directly. The NCCER HVACR case studies are 5 cases and about 2,825 words.
1Afternoon Comfort Complaint at a Bakery
A 1,150-square-foot bakery calls in July because the sales area never drops below 78°F after 2 p.m. The space is served by one 2-ton packaged rooftop unit, 9 years old, that also conditions the production area.
619 words, about 3 min2Carbon Monoxide Reading on a No-Heat Call
A technician responds to a no-heat call at a 22-year-old rental house on a 28°F evening. The 80% induced-draft furnace lights and runs, but the technician notices rust streaks at the flue collar and light soot on the burner box.
561 words, about 3 min3Low Suction Pressure After a Spring Top-Off
A 3-ton R-410A split system with a TXV is not keeping up on a 95°F day. Indoors the technician records 78°F dry bulb and 66°F wet bulb.
541 words, about 3 min4High-Limit Trips on a 90,000 Btu/h Furnace
A technician is called to a two-story house where the 90,000 Btu/h, 80% induced-draft furnace runs for about 12 minutes, trips the high-limit switch, and restarts after the blower cools the heat exchanger. The nameplate temperature rise range is 35-65°F.
543 words, about 3 min5Reusing an R-22 Line Set for an R-410A Changeout
A contractor is replacing a failed 3-ton R-22 condensing unit and coil with a new R-410A system in a two-story house. The existing line set is 40 feet long with 20 feet of vertical rise from the outdoor unit to the indoor coil, a 7/8-inch suction line and a 3/8-inch liquid line, and it is routed through finished walls with no accessible joints.
561 words, about 3 min