BPI Diagnostic Testing & Performance Evaluation 5

Question 1

What BPI standard governs the maximum acceptable undiluted CO level measured in the flue gases of a heating appliance?

Accepted Answer

400 ppm

Answer

BPI standards set 400 ppm as the action threshold for undiluted flue gas CO; levels above this require the appliance to be shut down and serviced.

Question 2

Which of the following best explains why blower door tests are conducted at 50 Pascals rather than natural pressure conditions?

Accepted Answer

Standardized pressure allows repeatable, comparable results across buildings and climates

Answer

Testing at 50 Pascals provides a standardized, repeatable pressure that amplifies leakage enough to measure accurately regardless of weather conditions or climate.

Question 3

A technician measures a pressure difference of -5 Pascals between a mechanical room and the outdoors during worst-case testing. What action is required?

Accepted Answer

The combustion appliances must be immediately shut off and not restarted until the issue is resolved

Answer

BPI protocols require shutting off combustion appliances when the mechanical room is depressurized beyond -5 Pascals (worst-case), as backdrafting risk is unacceptable.

Question 4

What does the term 'envelope leakage' refer to in BPI diagnostics?

Accepted Answer

Uncontrolled air movement through gaps in the building's thermal and pressure boundary

Answer

Envelope leakage refers to uncontrolled air infiltration and exfiltration through cracks, gaps, and penetrations in the building's outer shell.

Question 5

During a comprehensive diagnostic assessment, what is the purpose of measuring 'room-to-room' pressures with the air handler running?

Accepted Answer

To identify pressure imbalances that indicate return air pathway problems

Answer

Room pressure measurements with the AHU running reveal return air pathway restrictions that cause pressure imbalances, which can worsen infiltration and backdrafting risks.

(BPI) Building Performance Institute Certified Practice Test

(BPI) Building Performance Institute Certified Practice Test

BPI Diagnostic Testing & Performance Evaluation 5