NATE Low-GWP case studies
NATE Low-GWP · Put your knowledge to work in context.
The Low GWP Refrigerant Chevron is a recognition item sold through NATE's online shop, not a standalone proctored certification exam. On the NATE store page it appears under the categories NATE ID Required, Patches/Chevrons and NATE Patches, carries the tag LGWP, and is priced at $3.00 with the note that a NATE ID is required to order it. The NATE Low-GWP case studies are 5 cases and about 3,203 words.
1Charge Limit in a Mechanical Closet: R-454B Air Handler
You are commissioning a 3-ton R-454B split heat pump in a new townhouse. The air handler sits in a 5 ft × 6 ft × 8 ft mechanical closet - 240 ft³ - with a solid door and a 1-inch undercut.
751 words, about 4 min2Transcritical CO2 Rack: Opening a Case Circuit Safely
A convenience store has a transcritical R-744 booster rack. Outdoor ambient is 95°F, high-side pressure is 1,450 psig, and the gas cooler fans are cycling.
663 words, about 3 min3R-290 Undercounter Freezer in an Open Store
A grocery store has a built-in undercounter freezer with a nameplate charge of 5.3 oz (150 g) of R-290. A bubble test shows a slow leak at an evaporator pinhole.
613 words, about 3 min4The 'Just Change the Refrigerant' Request on an R-410A Rooftop
A 5-ton R-410A packaged rooftop unit, 11 years old and with a nameplate charge of 11 lb, serves a 2,000 ft² office. The customer read that R-410A is being phased down and asks you to 'swap in R-454B - it has to be cheaper than a new unit.' The unit has a reciprocating compressor, POE oil, and a TXV; the condenser coil is clean.
619 words, about 3 min5Recovered Blend in the Wrong Cylinder
You arrive at a 4-ton R-454B split system with a nameplate charge of 9.0 lb. The homeowner reports poor cooling since spring.
557 words, about 3 min