HVAC Study Sheet 2025 Questions and
Answers
What will happen when a steam turbine idles at its critical speed limit? - --
CORRECT ANSWER--The turbine will vibrate violently
What happens to the steam as it goes through each stage of the turbine? - --
CORRECT ANSWER--Steam pressure drops
What is the purpose of the steam ejectors or a surface condenser? - --CORRECT
ANSWER--To create a vacuum on the condenser for the steam exhaust.
What is the purpose of the Gland Steam Seal? - --CORRECT ANSWER--To
create positive pressure and eliminate leakage.
The governor on a steam turbine is used for... - --CORRECT ANSWER--
Automobile speed control
According to NYC Fire Code Classification of refrigerants, ammonia and sulfur
dioxide are grouped into: - --CORRECT ANSWER--Group 2
A reciprocating system using an evaporative condenser, the muffler is installed
between the: - --CORRECT ANSWER--Compressor and evaporative condenser
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 1
,Given a refrigeration system which includes a forced draft cooling tower, an
economizer and chilled water as the cooling medium the heat that is removed from
the building is finally rejected: - --CORRECT ANSWER--As heat of evaporation
on the cooling tower
You see the system is cycling normally, but the pressure and temperature is not: - --
CORRECT ANSWER--Poor condenser operating with dirty tubes
Low condensing pressure is not good because - --CORRECT ANSWER--
Expansion value will not feed properly
What is the purpose of installing a crank case vent line? - --CORRECT ANSWER-
-Prevent oil slugging in the compressor
Cylinder unloaders are used for: - --CORRECT ANSWER--Controlling capacity
An electric motor is to cut resistors by one half all other factors: - --CORRECT
ANSWER--Increased by a factor of 2
With respect to fire safety, which Ashrae refrigerant safety classifications is most
dangerous? - --CORRECT ANSWER--A3
How many BTU's would be removed on a 30 ton system? - --CORRECT
ANSWER--360,000 BTU/HRS
You have been informed that the temperatures has dropped by 10 degrees celsius.
The temperature in farenheit would be: - --CORRECT ANSWER--18
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 2
, What is the maximum percentage that the refrigerant can be stored in a cylinder? -
--CORRECT ANSWER--75%
Which refrigerant has the highest boiling point? - --CORRECT ANSWER--R-11
Where is the solenoid value located in between? - --CORRECT ANSWER--Sight
glass and filter dryer
Of the following, the most correct way to describe a brazed joint is: - --CORRECT
ANSWER--Gas tight fitting
Why should you charge with vapor? - --CORRECT ANSWER--Prevent from
freezing water in your tubes.
An inline refrigerant cleaner system is advisable because... - --CORRECT
ANSWER--Refrigerant reacts with lube oil
An automatic oil trap is installed in the high side of a refrigeration system, when
the flow of the trap lifts, it allows the: - --CORRECT ANSWER--Outside to leave
the trap and return to the compressor crank case
While doing a routine inspection, the RMO notices the bulb of the TEV is on the
floor and not strapped on, the operator should place the bulb: - --CORRECT
ANSWER--End of the coil
A rupture disk on a centrifugal refrigerant machine is normally located on the: - --
CORRECT ANSWER--Evaporator
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 3
Answers
What will happen when a steam turbine idles at its critical speed limit? - --
CORRECT ANSWER--The turbine will vibrate violently
What happens to the steam as it goes through each stage of the turbine? - --
CORRECT ANSWER--Steam pressure drops
What is the purpose of the steam ejectors or a surface condenser? - --CORRECT
ANSWER--To create a vacuum on the condenser for the steam exhaust.
What is the purpose of the Gland Steam Seal? - --CORRECT ANSWER--To
create positive pressure and eliminate leakage.
The governor on a steam turbine is used for... - --CORRECT ANSWER--
Automobile speed control
According to NYC Fire Code Classification of refrigerants, ammonia and sulfur
dioxide are grouped into: - --CORRECT ANSWER--Group 2
A reciprocating system using an evaporative condenser, the muffler is installed
between the: - --CORRECT ANSWER--Compressor and evaporative condenser
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 1
,Given a refrigeration system which includes a forced draft cooling tower, an
economizer and chilled water as the cooling medium the heat that is removed from
the building is finally rejected: - --CORRECT ANSWER--As heat of evaporation
on the cooling tower
You see the system is cycling normally, but the pressure and temperature is not: - --
CORRECT ANSWER--Poor condenser operating with dirty tubes
Low condensing pressure is not good because - --CORRECT ANSWER--
Expansion value will not feed properly
What is the purpose of installing a crank case vent line? - --CORRECT ANSWER-
-Prevent oil slugging in the compressor
Cylinder unloaders are used for: - --CORRECT ANSWER--Controlling capacity
An electric motor is to cut resistors by one half all other factors: - --CORRECT
ANSWER--Increased by a factor of 2
With respect to fire safety, which Ashrae refrigerant safety classifications is most
dangerous? - --CORRECT ANSWER--A3
How many BTU's would be removed on a 30 ton system? - --CORRECT
ANSWER--360,000 BTU/HRS
You have been informed that the temperatures has dropped by 10 degrees celsius.
The temperature in farenheit would be: - --CORRECT ANSWER--18
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 2
, What is the maximum percentage that the refrigerant can be stored in a cylinder? -
--CORRECT ANSWER--75%
Which refrigerant has the highest boiling point? - --CORRECT ANSWER--R-11
Where is the solenoid value located in between? - --CORRECT ANSWER--Sight
glass and filter dryer
Of the following, the most correct way to describe a brazed joint is: - --CORRECT
ANSWER--Gas tight fitting
Why should you charge with vapor? - --CORRECT ANSWER--Prevent from
freezing water in your tubes.
An inline refrigerant cleaner system is advisable because... - --CORRECT
ANSWER--Refrigerant reacts with lube oil
An automatic oil trap is installed in the high side of a refrigeration system, when
the flow of the trap lifts, it allows the: - --CORRECT ANSWER--Outside to leave
the trap and return to the compressor crank case
While doing a routine inspection, the RMO notices the bulb of the TEV is on the
floor and not strapped on, the operator should place the bulb: - --CORRECT
ANSWER--End of the coil
A rupture disk on a centrifugal refrigerant machine is normally located on the: - --
CORRECT ANSWER--Evaporator
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 3
