SHI Cheat Sheet 2026

The 30 highest-yield SHI facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. When using Solar Fraction (SF) as a performance metric, an SF value of 0.70 means: → 70% of the annual load is met by solar energy
2. Under the Americans with Disabilities Act (ADA), a solar thermal installation on a commercial building must ensure that: → Any controls or access panels at ground level are accessible to persons with disabilities
3. How do SHI professionals maintain digital competency? → Through ongoing training and staying current with technological advances
4. What maintenance should be done annually? → Check key system components and fluid
5. What is the primary factor evaluated during a solar site assessment to determine energy production potential? → Solar radiation availability (insolation)
6. Which hazard is common during installation of solar thermal systems? → Falls and thermal burns
7. A differential temperature controller in a solar thermal system typically activates the pump when collector temperature exceeds storage temperature by: → 5–10°F (3–6°C)
8. What is the first step in risk assessment for Solar Heating Installer Certification professionals? → Identifying potential hazards and vulnerabilities in the specific context
9. What type of collector is best for high-temperature applications? → Evacuated tube collector
10. A solar heating system emits a loud banging noise from the collector array shortly after the pump starts each morning. What is the most probable cause? → Air pockets rapidly collapsing as flow is established (air hammer)
11. A contractor who installs a solar thermal system without obtaining the required permits may face which of the following consequences? → Fines, mandatory removal of the system, and potential loss of contractor license
12. When an installer uses TRNSYS or similar simulation software to predict solar system performance, the output is considered: → A model-based performance estimate that should be validated against real monitored data
13. A solar thermal installer references SRCC OG-100 certification data when selecting collectors. What does this document provide? → Standardized thermal performance ratings tested under controlled conditions
14. A solar domestic hot water system is set to deliver water at 60°C (140°F) to prevent Legionella growth. What additional risk does this temperature introduce? → Scalding hazard at fixtures, requiring thermostatic mixing valves
15. What should be done after completing system installation? → Commission and test the system
16. Which organization certifies solar water heaters and issues the OG-300 certification mark? → SRCC (Solar Rating and Certification Corporation)
17. Why is it important to wear UV-protective sunglasses when handling unglazed or glazed flat-plate collectors during outdoor installation? → Both A and C are valid risks
18. In continuous process improvement for a solar installation company, a 'lessons learned' session after project completion primarily aims to: → Capture what worked and what failed so future projects benefit from the experience
19. When using solar design software to enter roof azimuth, which value represents true south orientation in the Northern Hemisphere? → 180°
20. In a drainback solar thermal system, what prevents collector freeze damage when the pump shuts off? → Water drains back to a reservoir by gravity
21. What distinguishes a peer-reviewed study from other publications? → Independent experts evaluated the methodology and conclusions before publication
22. Which type of sensor is most commonly integrated with a smart solar thermal controller to enable remote monitoring via the internet? → Pt1000 resistance temperature detector (RTD)
23. Why is periodic inspection important in solar thermal systems? → To identify and address system issues early
24. What is a common symptom of a malfunctioning controller? → No system response or incorrect data
25. What is the benefit of standardized digital reporting in Solar Heating Installer Certification practice? → It ensures consistency, enables comparison, and facilitates compliance
26. Which factor most significantly degrades solar thermal collector performance on an otherwise sunny, clear day? → Partial shading from a nearby obstruction
27. A solar domestic hot water system's backup electric element runs continuously even on sunny days. Which diagnostic check should be performed first? → Verify the solar loop is circulating and transferring heat to storage
28. What is the risk of not installing a check valve on the collector supply line of a thermosiphon or pump-driven solar system? → Reverse thermosiphoning at night, cooling the storage tank
29. When verifying collector array wiring on a photovoltaic-assisted solar thermal system, which quality check is specific to the electrical subsystem? → Verifying open-circuit voltage and short-circuit current match the module datasheet values
30. Which organization administers the NABCEP Solar Heating Installer certification in the United States? → NABCEP