NABCEP SHSI case studies
NABCEP SHSI · Put your knowledge to work in context.
The NABCEP Solar Heating Installer (SHI) certification is a North American Board of Certified Energy Practitioners credential aimed at professionals who design, install, commission, and maintain solar thermal systems - domestic hot water, space heating, and pool heating. It is intended for working installers and technicians who want independent verification of their competence in solar heating rather than photovoltaics. The NABCEP SHSI case studies are 5 cases and about 4,039 words.
1December Sizing for a Shaded Drainback DHW Retrofit
A four-person household at 44° latitude in a cold climate (design outdoor −20 °C) keeps an existing 60-gal electric tank at 60 °C. The owner wants solar to carry "most of our hot water" and has budgeted for three flat-plate collectors (4 × 8 ft, 32 ft² aperture each), a 120-gal drainback tank, and a 1/2 hp pump.
748 words, about 4 min2Coastal Metal-Roof Install: Correcting the Crew's Plan Before Penetration
A crew is installing a closed-loop glycol system on a two-story coastal house: four 4 × 10 ft flat-plate collectors (40 ft² each) on a 24-gauge standing-seam metal roof with 24-in. rafter spacing and a design wind speed of 110 mph.
802 words, about 4 min3Commissioning a Glycol Loop That Will Not Reach Design Flow
You are commissioning a new closed-loop glycol system: three 4 × 8 ft flat-plate collectors (96 ft² aperture), 30% propylene glycol, a 1/12 hp bronze pump rated 10 gpm at 8 ft of head, 3/4-in. copper supply and return, and a 30-gal diaphragm expansion tank precharged to 12 psi.
871 words, about 4 min4Five-Year Service Call: Degraded Glycol and a Lowered Setpoint
A homeowner calls in March because "the solar doesn't keep up anymore." The system is a five-year-old closed-loop glycol system with four collectors (128 ft²), a 120-gal solar tank with electric backup, and a thermostatic mixing valve. On site: glycol pH 6.1 (new fluid 9.5), freeze point −10 °C (original −30 °C), system cold pressure 6 psi (commissioned 20 psi), the automatic air vent has a dried crust trail down the pipe, and the collector glazing is hazy.
785 words, about 4 min5Inspection Findings on a Potable-Water Retrofit
You are asked to inspect a retrofit before the homeowner's final payment. The system preheats potable water through a single-wall copper coil immersed in a 100-gal tank that also contains 30% propylene glycol from the collector loop.
833 words, about 4 min