SHI Codes Compliance & Performance Testing 3 — Questions and Answers
Question 1: Which electrical code article primarily applies to the wiring of solar photovoltaic systems that may be paired with a solar thermal control system on the same structure?
- NEC Article 250
- NEC Article 690 (Correct answer)
- NEC Article 700
- NEC Article 800
Correct answer: NEC Article 690
NEC Article 690 covers the electrical installation requirements for solar photovoltaic systems, which are often co-located with solar thermal systems.
Question 2: Under the International Mechanical Code (IMC), solar thermal fluid piping that passes through fire-rated assemblies must be protected with:
- Pipe insulation only
- An approved fire stop system maintaining the fire-resistance rating (Correct answer)
- A metallic sleeve painted red
- A pressure gauge at every penetration
Correct answer: An approved fire stop system maintaining the fire-resistance rating
The IMC requires that any piping penetrating fire-rated walls or floors be sealed with an approved firestop system to restore the rated assembly.
Question 3: The SRCC OG-100 certification tests solar collectors under what simulated conditions to determine collector efficiency?
- Full moon irradiance and 0°C ambient
- Varying irradiance levels and inlet fluid temperatures relative to ambient temperature (Correct answer)
- Only peak irradiance at solar noon
- Manufacturer-specified optimal conditions only
Correct answer: Varying irradiance levels and inlet fluid temperatures relative to ambient temperature
OG-100 testing measures collector efficiency across a range of (Tin–Ta)/G values to produce an efficiency curve valid for diverse real-world conditions.
Question 4: A homeowner's HOA restricts roof modifications. Which federal or state-level legal principle often overrides HOA solar restrictions in most U.S. states?
- The Energy Policy Act of 2005
- Solar access laws or solar easement statutes adopted by most states (Correct answer)
- The Clean Air Act
- OSHA 1926 Subpart R
Correct answer: Solar access laws or solar easement statutes adopted by most states
Most U.S. states have enacted solar access or solar rights laws that limit HOAs' ability to prohibit solar installations on private property.
Question 5: During a system performance test, the instantaneous collector efficiency (η) is calculated using which formula?
- η = Q_useful / (A × G) (Correct answer)
- η = A × G / Q_useful
- η = (Tin – Tout) / G
- η = Q_useful × A × G
Correct answer: η = Q_useful / (A × G)
Instantaneous collector efficiency equals useful heat gain divided by the product of collector area and incident solar irradiance.
Question 6: Which inspection is typically required after solar thermal piping is installed but BEFORE it is insulated?
- Final electrical inspection
- Rough-in plumbing or pressure test inspection (Correct answer)
- Energy audit inspection
- Structural load calculation review
Correct answer: Rough-in plumbing or pressure test inspection
A rough-in inspection or pressure test allows the inspector to verify pipe connections and leak-free joints before insulation covers the piping.
Question 7: For a solar thermal system serving a commercial facility, which standard outlines commissioning procedures to verify system performance before occupancy?
- ASHRAE Guideline 0 and Guideline 1.1 (Correct answer)
- NFPA 101
- OSHA 29 CFR 1910
- IEEE 1547
Correct answer: ASHRAE Guideline 0 and Guideline 1.1
ASHRAE Guideline 0 (The Commissioning Process) and Guideline 1.1 (HVAC&R Technical Requirements for Commissioning) provide commissioning procedures applicable to solar thermal systems.
SHI Codes Compliance & Performance Testing 3
Which electrical code article primarily applies to the wiring of solar photovoltaic systems that may be paired with a solar thermal control system on the same structure?