NATE Exam: Core Test Refresher – Qs & As
Calculate the air volume based upon these conditions:
90,000 BTUH output
Return air temperature: 70F
Supply air temperature: 110F
a. 1,158 CFM
b. 1,500 CFM
c. 1,800 CFM
d. 2,083 CFM ✔️Ans - d (2,083 CFM)
When measuring CFM using temperature rise method, the furnace blower
motor speed should be in:
a. Continuous fan speed
b. Cool mode speed
c. Heat mode speed ✔️Ans - b (Cool mode speed)
If a single phase electric heat section is supplied with 225 volts and is drawing
45 AMPS, the BTUH output of the heat section is:
a. 34,500 BTUH
b. 25,000 BTUH
c. 45,000 BTUH ✔️Ans - a (34,500 BTUH)
When measuring temperature rise, take the supply air temperature directly in
line with the heater section of the air handler:
a. True
b. False ✔️Ans - b (False)
When measuring external static pressure, the high port of the pressure gauge
should be placed in the duct system to sense:
a. Supply air pressure
b. Return air pressure ✔️Ans - a (Supply air pressure)
, When the external static pressure rises, the delivered air volume will:
a. Increase
b. Decrease ✔️Ans - b (Decrease)
When measuring external static pressure on a gas furnace that utilizes an
evaporator coil, the supply air static pressure should be taken at:
a. The inlet to the evaporator
b. The outlet of the evaporator ✔️Ans - a (The inlet to the evaporator)
The pressure gauge used to sense external static pressure in a residential duct
system should have a pressure range scale of:
a. 0-1" water column
b. 0-5" water column
c. 0-10" water column ✔️Ans - a (0-1" water column)
If the velocity air in a 20 by 10 inch duct is 750 FPM, the air being delivered by
the duct is:
a. 1,209 CFM
b. 750 CFM
c. 1,042 CFM
d. 825 CFM ✔️Ans - c (1,042 CFM)
Taking average readings of air velocity in the cross sectional area of a duct is
called:
a. Traversing
b. Averaging
c. Estimating ✔️Ans - a (Traversing)
When the temperature of an object reaches absolute zero, the molecules of the
object will:
a. Cease movement
b. Move rapidly
Calculate the air volume based upon these conditions:
90,000 BTUH output
Return air temperature: 70F
Supply air temperature: 110F
a. 1,158 CFM
b. 1,500 CFM
c. 1,800 CFM
d. 2,083 CFM ✔️Ans - d (2,083 CFM)
When measuring CFM using temperature rise method, the furnace blower
motor speed should be in:
a. Continuous fan speed
b. Cool mode speed
c. Heat mode speed ✔️Ans - b (Cool mode speed)
If a single phase electric heat section is supplied with 225 volts and is drawing
45 AMPS, the BTUH output of the heat section is:
a. 34,500 BTUH
b. 25,000 BTUH
c. 45,000 BTUH ✔️Ans - a (34,500 BTUH)
When measuring temperature rise, take the supply air temperature directly in
line with the heater section of the air handler:
a. True
b. False ✔️Ans - b (False)
When measuring external static pressure, the high port of the pressure gauge
should be placed in the duct system to sense:
a. Supply air pressure
b. Return air pressure ✔️Ans - a (Supply air pressure)
, When the external static pressure rises, the delivered air volume will:
a. Increase
b. Decrease ✔️Ans - b (Decrease)
When measuring external static pressure on a gas furnace that utilizes an
evaporator coil, the supply air static pressure should be taken at:
a. The inlet to the evaporator
b. The outlet of the evaporator ✔️Ans - a (The inlet to the evaporator)
The pressure gauge used to sense external static pressure in a residential duct
system should have a pressure range scale of:
a. 0-1" water column
b. 0-5" water column
c. 0-10" water column ✔️Ans - a (0-1" water column)
If the velocity air in a 20 by 10 inch duct is 750 FPM, the air being delivered by
the duct is:
a. 1,209 CFM
b. 750 CFM
c. 1,042 CFM
d. 825 CFM ✔️Ans - c (1,042 CFM)
Taking average readings of air velocity in the cross sectional area of a duct is
called:
a. Traversing
b. Averaging
c. Estimating ✔️Ans - a (Traversing)
When the temperature of an object reaches absolute zero, the molecules of the
object will:
a. Cease movement
b. Move rapidly
