NABCEP NABCEP Solar Heating Installation Professional 3

Question 1

What is a thermosiphon solar water heating system and where is it commonly used?

Accepted Answer

A passive system where natural convection circulates fluid; common in mild climates with no freeze risk

Answer

A system using an electric pump driven by PV modules

Answer

A system using glycol under high pressure

Answer

A system that requires a differential controller to operate

Question 2

Which building code section requires solar water heating systems to be installed with a means of preventing scalding from excessively hot water?

Accepted Answer

UPC/IPC Plumbing Code sections requiring a tempering or mixing valve on solar water heaters

Answer

NEC Article 690

Answer

NFPA 72 fire alarm code

Answer

IBC structural section only

Question 3

What is the purpose of a check valve in an active solar thermal system's piping loop?

Accepted Answer

To prevent reverse thermosiphoning at night that would lose heat from the storage tank to the cold collectors

Answer

To increase system pressure

Answer

To filter debris from the fluid

Answer

To regulate pump speed

Question 4

Which installation orientation and tilt maximizes annual solar thermal energy collection in the continental US?

Accepted Answer

True south at a tilt angle approximately equal to the local latitude

Answer

Due east at 90°

Answer

Due west at 45°

Answer

Horizontal (0° tilt) facing any direction

Question 5

What is the primary advantage of a closed-loop solar thermal system over an open-loop system?

Accepted Answer

It protects the collector loop from freezing and corrosion while keeping potable water separate

Answer

It operates without a heat exchanger

Answer

It is always less expensive to install

Answer

It requires no expansion tank

Question 6

What does SRCC OG-300 certification indicate for a solar water heating system?

Accepted Answer

The complete solar water heating system has been rated and certified for annual energy performance

Answer

The collector alone meets efficiency standards

Answer

The system uses only certified PV modules

Answer

The installer is NABCEP certified