STATIONARY ENGINEERING EXAM WITH
VERIFIED QUESTIONS AND ANSWERS||
ALREADY GRADED A+ || GUARANTEED PASS ||
BEST VERSION 2025
What is an aqua stat? - ANSWER-a temperature sensing device. on a heating
system it is used to:
1) start and stop the burner
2) open a valve
3) start a fan
If you had an expansion tank on your system, where would it be located and
where would the water level be in it? Why don't all expansion tanks have sight
glasses? - ANSWER-It is usually located near the top of the system with the
water level midway in the tank. The level will go up and down as the
temperature and pressure changes. The tank may use a bladder or a diaphragm
eliminating the need for a sight glass.
If you have a water boiler and you discover the sight glass on the expansion
tank was completely full and the system pressure was higher than normal. What
will happen next and how will you correct it? - ANSWER-The relief valve will
relieve excess pressure. I would isolate and drain the tank and repair the leaks
by tightening the fittings and replacing sight glass washers before refilling the
tank.
What are pumps used for? Name 5 types of pumps? - ANSWER-Heating water,
cooling water, boiler feed, lubrication, condensing water, sumps and boosters.
1. Centrifugal
,2. Rotary
3. Injector
4. Duplex
5. Simplex
6. Vacuum
Explain how an injector works. - ANSWER-It is a device designed to lift and
force water into a boiler that is operating under pressure. It operates on the
principle of steam expanding through a nozzle imparting its velocity energy to a
mass of water.
What is lost motion? - ANSWER-It is a steam driven, double acting,
reciprocating pump with check valves on both sides of the pistons so liquid is
pumped no matter which way the piston is moving. Lost motion is the distance
between the lugs and nut on the back side of the "D" slide valve enabling the
valve to close slowly and quietly before the pump reverses the stroke.
What is an air chamber and why is it used? - ANSWER-It is located on the
intake or discharge of a reciprocating pump. It absorbs the shock and surges of
the liquid being pumped relieving the pump from excessive strains.
What is a foot valve and its purpose? - ANSWER-It is a type of check valve
located at the bottom end of a suction line to prevent pump from loosing prime
and from running backward when shut down.
What are its uses in a power plant? - ANSWER-They are either diaphragm,
piston or plunger operated positive displacement pumps used for low flow
applications. 3 features are accuracy of adjustment, capable of pumping wide
variety chemicals and high head service. They are used for injecting cooling
tower treatment, internal boiler treatment or external boiler treatment.
,What is the difference between a piston and a plunger? - ANSWER-A plunger
moves inside stationary rings installed in grooves in the cylinder. A piston has
rings installed in grooves in the piston itself.
Define volt. Define ampere. - ANSWER-a force or pressure which causes an
electron flow of one ampere through a resistance of one ohm
----
one ampere of current is said to flow when one coulomb of electricity passes a
given point in a conductor in one second
Define Ohm's Law - ANSWER--Current passing through a conductor is directly
proportional to the voltage and inversely proportional to the resistance.
If in a 240v circuit you have a 20- amp load, what will your resistance be? If
you have a 2400w heater and a 240v service, what would your amperage be? -
ANSWER-R= V/I 240v/20a= 12 ohms
I= watts/volts 2400w/240v= 10a
Using 100' long wire, which will have more resistance. A no. 12 or a no. 14
wire? - ANSWER-No. 14 because the wire is smaller.
What is alternating current? What is direct current? What are 4 advantages of
each? - ANSWER-Alternating current is a periodic current, which has an
average value or zero.
What problem do you watch for when paralleling 2 centrifugal pumps? -
ANSWER-Make sure that pump capacities stay the same so that one pump does
not hog the load.
What are the merits of a centrifugal pump? - ANSWER-1) few moving parts
, 2) uniform flow
3) easy to control
4) high capacities
5) dependable
6) long life
What would you do if your b.f.w.p. Became steam bound? - ANSWER-Throttle
the discharge a little. Cool the pump with a garden hose or maybe install a city
water tap to the suction of the pump. Then find the cause.
Is a check valve placed after a pump and why? - ANSWER-YES * a check
valve relieves the pump of start up pressure and prevents injury to the pump
from back-pressure causing pump to run backwards
Define N.P.S.H. - ANSWER-Net positive suction head. The amount of positive
pressure on the inlet of the pump when the pump is on.
How do you adjust the flow rate of a centrifugal pump? What would happen if
the discharge valve was closed on a centrifugal pump? - ANSWER-By
throttling the discharge valve or by changing the speed of the motor. Too much
throttling may require the installation of a bypass. If the valve is closed
completely or throttled too much, the pump will slowly overheat.
Why is the suction opening on a pump larger than the discharge opening? -
ANSWER-1) provide a constant capacity & volume
2) ensure a smooth flow
How is power measured? What is a watt? How many watts in a kilowatt? How
many watts in 1 horsepower? - ANSWER-Power is measured in watts.
VERIFIED QUESTIONS AND ANSWERS||
ALREADY GRADED A+ || GUARANTEED PASS ||
BEST VERSION 2025
What is an aqua stat? - ANSWER-a temperature sensing device. on a heating
system it is used to:
1) start and stop the burner
2) open a valve
3) start a fan
If you had an expansion tank on your system, where would it be located and
where would the water level be in it? Why don't all expansion tanks have sight
glasses? - ANSWER-It is usually located near the top of the system with the
water level midway in the tank. The level will go up and down as the
temperature and pressure changes. The tank may use a bladder or a diaphragm
eliminating the need for a sight glass.
If you have a water boiler and you discover the sight glass on the expansion
tank was completely full and the system pressure was higher than normal. What
will happen next and how will you correct it? - ANSWER-The relief valve will
relieve excess pressure. I would isolate and drain the tank and repair the leaks
by tightening the fittings and replacing sight glass washers before refilling the
tank.
What are pumps used for? Name 5 types of pumps? - ANSWER-Heating water,
cooling water, boiler feed, lubrication, condensing water, sumps and boosters.
1. Centrifugal
,2. Rotary
3. Injector
4. Duplex
5. Simplex
6. Vacuum
Explain how an injector works. - ANSWER-It is a device designed to lift and
force water into a boiler that is operating under pressure. It operates on the
principle of steam expanding through a nozzle imparting its velocity energy to a
mass of water.
What is lost motion? - ANSWER-It is a steam driven, double acting,
reciprocating pump with check valves on both sides of the pistons so liquid is
pumped no matter which way the piston is moving. Lost motion is the distance
between the lugs and nut on the back side of the "D" slide valve enabling the
valve to close slowly and quietly before the pump reverses the stroke.
What is an air chamber and why is it used? - ANSWER-It is located on the
intake or discharge of a reciprocating pump. It absorbs the shock and surges of
the liquid being pumped relieving the pump from excessive strains.
What is a foot valve and its purpose? - ANSWER-It is a type of check valve
located at the bottom end of a suction line to prevent pump from loosing prime
and from running backward when shut down.
What are its uses in a power plant? - ANSWER-They are either diaphragm,
piston or plunger operated positive displacement pumps used for low flow
applications. 3 features are accuracy of adjustment, capable of pumping wide
variety chemicals and high head service. They are used for injecting cooling
tower treatment, internal boiler treatment or external boiler treatment.
,What is the difference between a piston and a plunger? - ANSWER-A plunger
moves inside stationary rings installed in grooves in the cylinder. A piston has
rings installed in grooves in the piston itself.
Define volt. Define ampere. - ANSWER-a force or pressure which causes an
electron flow of one ampere through a resistance of one ohm
----
one ampere of current is said to flow when one coulomb of electricity passes a
given point in a conductor in one second
Define Ohm's Law - ANSWER--Current passing through a conductor is directly
proportional to the voltage and inversely proportional to the resistance.
If in a 240v circuit you have a 20- amp load, what will your resistance be? If
you have a 2400w heater and a 240v service, what would your amperage be? -
ANSWER-R= V/I 240v/20a= 12 ohms
I= watts/volts 2400w/240v= 10a
Using 100' long wire, which will have more resistance. A no. 12 or a no. 14
wire? - ANSWER-No. 14 because the wire is smaller.
What is alternating current? What is direct current? What are 4 advantages of
each? - ANSWER-Alternating current is a periodic current, which has an
average value or zero.
What problem do you watch for when paralleling 2 centrifugal pumps? -
ANSWER-Make sure that pump capacities stay the same so that one pump does
not hog the load.
What are the merits of a centrifugal pump? - ANSWER-1) few moving parts
, 2) uniform flow
3) easy to control
4) high capacities
5) dependable
6) long life
What would you do if your b.f.w.p. Became steam bound? - ANSWER-Throttle
the discharge a little. Cool the pump with a garden hose or maybe install a city
water tap to the suction of the pump. Then find the cause.
Is a check valve placed after a pump and why? - ANSWER-YES * a check
valve relieves the pump of start up pressure and prevents injury to the pump
from back-pressure causing pump to run backwards
Define N.P.S.H. - ANSWER-Net positive suction head. The amount of positive
pressure on the inlet of the pump when the pump is on.
How do you adjust the flow rate of a centrifugal pump? What would happen if
the discharge valve was closed on a centrifugal pump? - ANSWER-By
throttling the discharge valve or by changing the speed of the motor. Too much
throttling may require the installation of a bypass. If the valve is closed
completely or throttled too much, the pump will slowly overheat.
Why is the suction opening on a pump larger than the discharge opening? -
ANSWER-1) provide a constant capacity & volume
2) ensure a smooth flow
How is power measured? What is a watt? How many watts in a kilowatt? How
many watts in 1 horsepower? - ANSWER-Power is measured in watts.
