SHI Installation Techniques & Safety Procedures 2 — Questions and Answers
Question 1: When installing flat-plate collectors on a roof with a pitch below 15 degrees, what additional measure is typically required?
- Install tilt frames to achieve the minimum recommended angle (Correct answer)
- Use evacuated tube collectors instead
- Add a second pump to compensate for reduced flow
- Install a larger expansion tank
Correct answer: Install tilt frames to achieve the minimum recommended angle
Tilt frames are used to achieve the optimal collector angle when the roof pitch is insufficient for efficient solar gain.
Question 2: Which type of pipe insulation is most appropriate for outdoor solar thermal piping exposed to UV radiation?
- Standard foam pipe insulation
- UV-resistant closed-cell foam or armaflex with a UV-protective jacket (Correct answer)
- Fiberglass wrap insulation
- Cotton batting with a foil face
Correct answer: UV-resistant closed-cell foam or armaflex with a UV-protective jacket
UV-resistant closed-cell foam insulation with a protective jacket prevents degradation from sun exposure in outdoor installations.
Question 3: During a pressure test of a newly installed solar thermal system, the installer notices a gradual pressure drop over 30 minutes. What is the most likely cause?
- Normal thermal expansion of the fluid
- A leak in the piping or fittings (Correct answer)
- Excessive pump speed
- Air trapped in the collector loop
Correct answer: A leak in the piping or fittings
A gradual pressure drop during a static pressure test indicates a leak somewhere in the system that must be located and repaired.
Question 4: What is the primary purpose of a vacuum relief valve in a drainback solar thermal system?
- To prevent the system from exceeding maximum operating pressure
- To allow air to enter the collector loop so water can drain back to the tank (Correct answer)
- To release steam if the fluid overheats
- To maintain system pressure during cold weather
Correct answer: To allow air to enter the collector loop so water can drain back to the tank
A vacuum relief valve allows air into the collector loop when the pump shuts off, enabling the water to drain back by gravity to the storage tank.
Question 5: When soldering copper fittings on a solar thermal system, which flux type should be used on potable water lines?
- Acid-based flux for stronger joints
- Lead-based flux for high-temperature applications
- Lead-free, water-soluble flux approved for potable water (Correct answer)
- Any plumber's flux available at a hardware store
Correct answer: Lead-free, water-soluble flux approved for potable water
Lead-free, water-soluble flux must be used on potable water lines to comply with health and safety regulations and prevent contamination.
Question 6: An installer is working on a roof in direct sun on a 90°F day. Which safety precaution is MOST important for preventing heat-related illness?
- Wear a reflective vest
- Take scheduled hydration breaks and watch for early symptoms of heat exhaustion (Correct answer)
- Work only in the morning hours
- Use a portable fan on the roof
Correct answer: Take scheduled hydration breaks and watch for early symptoms of heat exhaustion
Regular hydration combined with monitoring for symptoms like dizziness and heavy sweating is the most critical defense against heat-related illness.
Question 7: What is the recommended minimum clearance between a solar collector array and the roof edge to prevent wind uplift damage?
- No clearance is needed if properly anchored
- At least 6 inches from the roof edge
- The clearance recommended by the collector manufacturer and local wind load codes (Correct answer)
- Exactly 24 inches from all edges
Correct answer: The clearance recommended by the collector manufacturer and local wind load codes
Clearance requirements are determined by the collector manufacturer's specifications combined with local building codes for wind uplift resistance.
SHI Installation Techniques & Safety Procedures 2
When installing flat-plate collectors on a roof with a pitch below 15 degrees, what additional measure is typically required?