MD STATIONARY ENGINEER EXAM SCRIPT 2025/2026
QUESTIONS WITH ANSWERS GRADED A+
✔✔HeatPump - ✔✔Heat Pump
An air conditioner that contains a valve that allows it to alternate between heating and
cooling.
✔✔Humidity - ✔✔Humidity
The amount of moisture in the air.
✔✔Relative humidity - ✔✔Relative humidity
The ratio of the amount of vapor contained in the air to the greatest amount the air could
hold at that temperature. Normally expressed as a percentage.
✔✔Super-Heated Vapor - ✔✔Refrigerant vapor heated beyond its saturation point.
✔✔Vacuum Pump - ✔✔A pump used to remove air and moisture from a refrigeration
system at a pressure below atmospheric pressure.
✔✔Water Cooled System - ✔✔Water Cooled System
A type of air conditioning system that uses freon as a refrigerant and water as a
condensing medium. Typically, the water-cooled condenser is located inside the air
conditioner with the rest of the refrigeration components. Water is piped to the unit from
a cooling tower or other suitable source.
✔✔Zoning - ✔✔Zoning
The practice of providing independent heating and/or cooling to different areas in a
structure. Zoning typically utilizes a system controller, zoning dampers controlled by a
thermostat in each zone, and a bypass damper to regulate static pressure in the supply
duct.
✔✔Bolwdown Tanks - ✔✔Blowdown Tanks: Manage Temperature and Pressure
Boiler blowdown tanks are used to reduce the pressure and temperature of the
blowdown from a boiler. IN most states, it is unlawful to discharge blowdown directly
into the sewer system. They typically require boiler blowdown to be reduced to a
temperature of 140° F at a maximum pressure of 5PSIG.
✔✔BDS Blowdown Separators - ✔✔BDS Blowdown Separators
Precision Boilers' blowdown separators are used to temper high pressure boiler water to
an acceptable drain temperature. They are used where space constraints preclude the
use of blowdown tanks.
✔✔FT Flash Tanks - ✔✔FT Flash Tanks
Boiler flash tanks are used in systems that require flashing of high pressure condensate
to reduce its pressure and temperature before it is returned to the condensate receiver
, or discharged into the sewer. Flash tanks are provided with an inlet for
condensate/steam, plus outlet, vent and drain connections.
✔✔AIR ATOMIZING OIL BURNER - ✔✔A burner for firing oil in which the oil is
atomized by compressed air, which is forced into and through one or more streams of
oil which results in the breaking of the oil into a fine spray
✔✔AIR VENT - ✔✔A valved opening in the top of the highest drum of a boiler or
pressure vessel for venting air.
✔✔ALKALINITY - ✔✔Represents the amount of carbonates, bicarbonates, hydroxides
and silicates or phosphates in the water and is reported as grains per gallon, or ppm as
calcium carbonate.
✔✔AQUASTAT - ✔✔Water limit temperature control, a safety device often used on
boilers.
✔✔ATOMIZER - ✔✔A device by means of which a liquid is reduced to a very fine spray.
✔✔AVAILABLE DRAFT - ✔✔The draft which may be utilized to cause the flow of air for
combustion or the flow of products of combustion.
✔✔BAFFLE - ✔✔A plate or wall for deflecting gases or liquids.
✔✔BAROMETRIC PRESSURE - ✔✔Atmospheric pressure as determined by a
barometer usually expressed in inches of mercury.
✔✔BLOWDOWN - ✔✔Boiler water that is removed from the boiler in order to maintain
the desired concentration levels of suspended and dissolved solids in the boiler and
removal of sludge.
✔✔BLOWDOWN SAFETY VALVE - ✔✔The difference between the pressure at which a
safety valve opens and at which it closes.
✔✔BLOWDOWN VALVE - ✔✔A valve generally used to continuously regulate
concentration of solids in the boiler, not a drain valve. (Often called continuous
blowdown.)
✔✔BLOW-OFF VALVE - ✔✔A specially designed, manually operated, valve that
connects to the boiler for the purpose of reducing the concentration of solids in the
boiler or for draining purposes. (Often called bottom blowdown.)
✔✔BLOWER - ✔✔A fan used to force air under pressure.
QUESTIONS WITH ANSWERS GRADED A+
✔✔HeatPump - ✔✔Heat Pump
An air conditioner that contains a valve that allows it to alternate between heating and
cooling.
✔✔Humidity - ✔✔Humidity
The amount of moisture in the air.
✔✔Relative humidity - ✔✔Relative humidity
The ratio of the amount of vapor contained in the air to the greatest amount the air could
hold at that temperature. Normally expressed as a percentage.
✔✔Super-Heated Vapor - ✔✔Refrigerant vapor heated beyond its saturation point.
✔✔Vacuum Pump - ✔✔A pump used to remove air and moisture from a refrigeration
system at a pressure below atmospheric pressure.
✔✔Water Cooled System - ✔✔Water Cooled System
A type of air conditioning system that uses freon as a refrigerant and water as a
condensing medium. Typically, the water-cooled condenser is located inside the air
conditioner with the rest of the refrigeration components. Water is piped to the unit from
a cooling tower or other suitable source.
✔✔Zoning - ✔✔Zoning
The practice of providing independent heating and/or cooling to different areas in a
structure. Zoning typically utilizes a system controller, zoning dampers controlled by a
thermostat in each zone, and a bypass damper to regulate static pressure in the supply
duct.
✔✔Bolwdown Tanks - ✔✔Blowdown Tanks: Manage Temperature and Pressure
Boiler blowdown tanks are used to reduce the pressure and temperature of the
blowdown from a boiler. IN most states, it is unlawful to discharge blowdown directly
into the sewer system. They typically require boiler blowdown to be reduced to a
temperature of 140° F at a maximum pressure of 5PSIG.
✔✔BDS Blowdown Separators - ✔✔BDS Blowdown Separators
Precision Boilers' blowdown separators are used to temper high pressure boiler water to
an acceptable drain temperature. They are used where space constraints preclude the
use of blowdown tanks.
✔✔FT Flash Tanks - ✔✔FT Flash Tanks
Boiler flash tanks are used in systems that require flashing of high pressure condensate
to reduce its pressure and temperature before it is returned to the condensate receiver
, or discharged into the sewer. Flash tanks are provided with an inlet for
condensate/steam, plus outlet, vent and drain connections.
✔✔AIR ATOMIZING OIL BURNER - ✔✔A burner for firing oil in which the oil is
atomized by compressed air, which is forced into and through one or more streams of
oil which results in the breaking of the oil into a fine spray
✔✔AIR VENT - ✔✔A valved opening in the top of the highest drum of a boiler or
pressure vessel for venting air.
✔✔ALKALINITY - ✔✔Represents the amount of carbonates, bicarbonates, hydroxides
and silicates or phosphates in the water and is reported as grains per gallon, or ppm as
calcium carbonate.
✔✔AQUASTAT - ✔✔Water limit temperature control, a safety device often used on
boilers.
✔✔ATOMIZER - ✔✔A device by means of which a liquid is reduced to a very fine spray.
✔✔AVAILABLE DRAFT - ✔✔The draft which may be utilized to cause the flow of air for
combustion or the flow of products of combustion.
✔✔BAFFLE - ✔✔A plate or wall for deflecting gases or liquids.
✔✔BAROMETRIC PRESSURE - ✔✔Atmospheric pressure as determined by a
barometer usually expressed in inches of mercury.
✔✔BLOWDOWN - ✔✔Boiler water that is removed from the boiler in order to maintain
the desired concentration levels of suspended and dissolved solids in the boiler and
removal of sludge.
✔✔BLOWDOWN SAFETY VALVE - ✔✔The difference between the pressure at which a
safety valve opens and at which it closes.
✔✔BLOWDOWN VALVE - ✔✔A valve generally used to continuously regulate
concentration of solids in the boiler, not a drain valve. (Often called continuous
blowdown.)
✔✔BLOW-OFF VALVE - ✔✔A specially designed, manually operated, valve that
connects to the boiler for the purpose of reducing the concentration of solids in the
boiler or for draining purposes. (Often called bottom blowdown.)
✔✔BLOWER - ✔✔A fan used to force air under pressure.
