HVACR FINAL PAPER 2026 FULL
QUESTIONS AND CORRECT ANSWERS
◉ What is the effect of 170 volts supplied to a 208/230 volt
compressor?
Answer: Would cause the current to increase and the motor may trip
on overload.
◉ On a service call for a cooling problem with a heat pump, your
inspections find a liquid line that has condensation on it. What is
most likely to cause this?
Answer: Restriction in the liquid line.
◉ What is a reason for cool air complaints when a heat pump is
operating in the heating cycle?
Answer: Excessive supply air velocities.
◉ The following measurements are recorded on an operating heat
pump system. The heat pump is operating with the compressor only
with no auxiliary heat:
• Heat pump only supply air temperature 92°F
,• Heat pump only return air temperature 70°F
• Outdoor temperature 54°F
• Supply air temp. /auxiliary heat ON 115°F
• Return air temp. /auxiliary heat ON 70°F
• CFM 1228
What is the heating capacity in BTUH?
Answer: 29,177 BTU/H
◉ Inadequate heating can be caused by what?
Answer: Dirty or clogged air filter.
◉ To minimize noise problems in residential duct systems, what is
the range (recommended to maximum) of design air velocity in the
rectangular main supply trunk?
Answer: 700 to 900 fpm
◉ conditions while checking a packaged heat pump in cooling.
, • The unit has a piston type metering device on both the indoor and
outdoor coils.
• Outdoor temperature 75°F
• Superheat 55°F
What is wrong with the system?
Answer: Undercharged.
◉ What will you get when a capillary tube is overcharged?
Answer: low superheat and high sub cooling
◉ What is the effect of a low charge on the switchover operations of
a reversing valve?
Answer: Reversing valves are less likely to transfer if charge is low.
◉ A technician is working on a heat pump with a capacitor start-
capacitor run compressor. On initial startup, the compressor hums
momentarily and the shuts down on internal overload. What is the
problem?
Answer: Too great a pressure difference on the compressor.
QUESTIONS AND CORRECT ANSWERS
◉ What is the effect of 170 volts supplied to a 208/230 volt
compressor?
Answer: Would cause the current to increase and the motor may trip
on overload.
◉ On a service call for a cooling problem with a heat pump, your
inspections find a liquid line that has condensation on it. What is
most likely to cause this?
Answer: Restriction in the liquid line.
◉ What is a reason for cool air complaints when a heat pump is
operating in the heating cycle?
Answer: Excessive supply air velocities.
◉ The following measurements are recorded on an operating heat
pump system. The heat pump is operating with the compressor only
with no auxiliary heat:
• Heat pump only supply air temperature 92°F
,• Heat pump only return air temperature 70°F
• Outdoor temperature 54°F
• Supply air temp. /auxiliary heat ON 115°F
• Return air temp. /auxiliary heat ON 70°F
• CFM 1228
What is the heating capacity in BTUH?
Answer: 29,177 BTU/H
◉ Inadequate heating can be caused by what?
Answer: Dirty or clogged air filter.
◉ To minimize noise problems in residential duct systems, what is
the range (recommended to maximum) of design air velocity in the
rectangular main supply trunk?
Answer: 700 to 900 fpm
◉ conditions while checking a packaged heat pump in cooling.
, • The unit has a piston type metering device on both the indoor and
outdoor coils.
• Outdoor temperature 75°F
• Superheat 55°F
What is wrong with the system?
Answer: Undercharged.
◉ What will you get when a capillary tube is overcharged?
Answer: low superheat and high sub cooling
◉ What is the effect of a low charge on the switchover operations of
a reversing valve?
Answer: Reversing valves are less likely to transfer if charge is low.
◉ A technician is working on a heat pump with a capacitor start-
capacitor run compressor. On initial startup, the compressor hums
momentarily and the shuts down on internal overload. What is the
problem?
Answer: Too great a pressure difference on the compressor.
