BOC Energy Conservation Techniques 3

Question 1

A steam trap stuck open on a 100 psig line causes energy loss mainly by:

Accepted Answer

Allowing live steam to pass into the condensate system

Answer

Failed-open traps pass live steam, wasting the energy used to generate it.

Question 2

What is the typical energy-saving effect of lowering boiler excess air from 50% to 15% on a gas-fired boiler?

Accepted Answer

Reduced stack heat loss and higher combustion efficiency

Answer

Less excess air means less air to heat and send up the stack, which raises combustion efficiency.

Question 3

Which instrument is most appropriate for finding missing insulation and air leaks in a building envelope?

Accepted Answer

Infrared thermal imaging camera

Answer

Infrared cameras show temperature differences on surfaces that reveal insulation voids and air infiltration.

Question 4

Variable frequency drives on chilled water pumps save the most energy in which type of system?

Accepted Answer

Variable-flow system with two-way control valves

Answer

Two-way valves let flow vary with load, so the VFD can slow the pump and cut power.

Question 5

An energy audit level that includes detailed analysis of capital-intensive measures with investment-grade savings estimates is typically called:

Accepted Answer

Detailed analysis of capital-intensive modifications (ASHRAE Level 3)

Answer

ASHRAE Level 3 audits give investment-grade analysis for major capital projects.

BOC - Building Operator Certification Practice Test