NATE Airflow Tools Measurement Exam Questions with Certified Answers Graded A+

A strobe tachometer is used to measure - Answer: Blower speed A strobe tachometer's measurements are in - Answer: RPM A Pitot-tube has the capability of measuring - Answer: Velocity and static pressure The holes on the side of a Pitot-tube are used to measure - Answer: Static pressure The hole on the end of a Pitot-tube is used to measure - Answer: Total pressure The speed of air in a duct system is measured in - Answer: FPM, (feet per minute) A Pitot-tube traverse is commonly used to - Answer: Take an average air velocity pressure reading A Pitot-tube traverse - Answer: Can be taken in the main supply, return, and individual branch runs A velometer measures - Answer: The speed of the air in a duct system or at a diffuser Instrument commonly used with velometer to measure air velocity at supply air register - Answer: A diffuser probe An anemometer measures - Answer: Velocity in feet per minute Two common types of anemometers used for airflow testing are - Answer: A hot wire and a vane type What is considered static pressure in a duct system - Answer: The pressure of air pushing equally in all directions in the duct system What instrument must be used with a manometer to measure static, velocity, and total pressure - Answer: A Pitot-tube Total Pressure = - Answer: Static Pressure + Velocity Pressure A U-tube manometer is commonly used to measure pressures - Answer: That are above 1" WC An incline manometer is commonly used to measure pressures - Answer: That are below 1" WC What type of gauge uses a high and low pressure port to measure a pressure difference between two different locations - Answer: A differential pressure gauge Air volume is measured in - Answer: CFM (cubic feet per minute) CFM= - Answer: Velocity X Area An 8" X 22" supply air duct, 1000 fpm, what quantity of air moves through the system - Answer: 1,222 cfm 8" X 12" register, velocity 300 fpm, free area of 75%, what quantity of air moves through the system - Answer: 200 cfm An airhood is commonly used for measuring - Answer: CFM (cubic feet per minute) Output (Btu/h /1.08 X temperature difference = - Answer: CFM (cubic feet per minute) The temperature difference across a heat exchanger is 70* F and furnace output is 82,000 BTU/h what is CFM of the blower - Answer: 1,085 cfm