Steamfitter RED SEAL Exam 2025
Questions 100% Correct Solutions
What pipe shall not be used for flammable fluids? - ANSWER Cast iron pipe or ASTM
A53 and A120 furnace butt welded steel pipe
What pipe must be used for threaded applications in steam service at pressure
above 250psig or water service above 100psig? - ANSWER Seamless sch 80 minimum
How far above the highest point of the tubes, flues or crown sheets must the water
be in a horizontal firetube boiler be? - ANSWER 3"
What is the minimum diameter of a valve connection for test guages on a boiler?
- ANSWER 1/4"
What is a breaching? - ANSWER Where the products of combustion are allowed outside of
the boiler and are now called flue gas (location of ID fan, economizer & air heater
What additional equipment is located at the burner assembly? - ANSWER An igniter and
sensors for proof of pilot flame when the main burner has started, stopped or failed
Where is the safety valve connected on a steam boiler? - ANSWER In the steam space of
the shell
What prevents the boiler from collapsing when the boiler shuts down and begins to
loose pressure and cool? - ANSWER A vacuum breaker or thermostatic steam trap
,What configurations are water tube boilers made in? - ANSWER D, O, A
What are the upper/lower drums of a water tube boiler called, respectively? - ANSWER
Steam drum and mud drum (or water drum)
What are the deposits in the bottom drum of a water tube boiler called? - ANSWER Mud
and scale
Where are water tube boilers usually used? - ANSWER I'm high pressure
applications requiring saturated steam for heating or process work
Why are water tube boilers more cost effective in larger capacities - ANSWER The
shell on the steam drum is smaller and can be thinner
How often does the furnace walk of an oil fired boiler need to be cleaned? - ANSWER
Annually
What is the operating pressure range in a water tube boiler? - ANSWER Usually up
to 250psig
But in some cases 900psig
What equipment does the steam drum in a boiler contain? - ANSWER Feed water
distributor pipe, steam drum baffles, steam nozzles off the top of the drum, as well
as the holes for the tube attachments on the bottom portion of the drum
What is a cyclone separator - ANSWER An internal steam separator that uses
centrifugal force to remove the water from the steam-water
,What are steam main lines graded at? - ANSWER 1" per 20ft
Where is a stop valve placed on the boiler feed water piping? - ANSWER Between
the check valve and the boiler
How large must the feed water connection to the boiler be for 100sqft or less
heating surface? - ANSWER 1/2"
How large just the feed water connection to the boiler be for boilers with a
heating surface greater than 100sqft? - ANSWER 3/4"
How many full turns must a master valve on a blowdown line have? - ANSWER 5 full
turns
Why types of quick opening valves can be on a blowdown line? - ANSWER Gate or glove
valve
Order of valve opening on a blowdown line? - ANSWER Q, M, M, Q
How often are blow off systems in the mud drum operated? - ANSWER Intermittently
How often are blowdown systems in the steam drum operated? - ANSWER Continuously
TDS - ANSWER Total dissolved solids
Minimum blow off line size is 1" except where? - ANSWER Except on boilers having less
than 100sqft of heating surface, then it's 3/4"
, Maximum blow off line size? - ANSWER 2 1/2"
When must check valves be installed on blow off lines, where? - ANSWER When
there are 2 boiler blow offs connected to a common blow off header. Check valve
must be installed between header and downstream of blowdown valves
What is the maximum pressure design of a blowdown tank - ANSWER 30% of maximum
pressure up to 300psig
What temperature must effluent discharge to a draining system be? - ANSWER
Less than 75°C
What also acts as a flash steam vessel to cool condensate in the system? - ANSWER
Blowdown tank
How far up the blowdown tank does the blow off enter - ANSWER 3/4 of the way up
What is an attachment to the first nozzle or flange of a boiler called - ANSWER
Boiler trim
What does double block and bleed mean - ANSWER Bleed valve may be attached to
a nipple tee's into the pipe or may be tapped into the body of the block valve
Why are block and bleed valves used - ANSWER To prevent contaminating organisms
from entering the process
How many safety valves shall a boiler with more than 500sqft of heating surface be
equipped with? - ANSWER 2 or more
Questions 100% Correct Solutions
What pipe shall not be used for flammable fluids? - ANSWER Cast iron pipe or ASTM
A53 and A120 furnace butt welded steel pipe
What pipe must be used for threaded applications in steam service at pressure
above 250psig or water service above 100psig? - ANSWER Seamless sch 80 minimum
How far above the highest point of the tubes, flues or crown sheets must the water
be in a horizontal firetube boiler be? - ANSWER 3"
What is the minimum diameter of a valve connection for test guages on a boiler?
- ANSWER 1/4"
What is a breaching? - ANSWER Where the products of combustion are allowed outside of
the boiler and are now called flue gas (location of ID fan, economizer & air heater
What additional equipment is located at the burner assembly? - ANSWER An igniter and
sensors for proof of pilot flame when the main burner has started, stopped or failed
Where is the safety valve connected on a steam boiler? - ANSWER In the steam space of
the shell
What prevents the boiler from collapsing when the boiler shuts down and begins to
loose pressure and cool? - ANSWER A vacuum breaker or thermostatic steam trap
,What configurations are water tube boilers made in? - ANSWER D, O, A
What are the upper/lower drums of a water tube boiler called, respectively? - ANSWER
Steam drum and mud drum (or water drum)
What are the deposits in the bottom drum of a water tube boiler called? - ANSWER Mud
and scale
Where are water tube boilers usually used? - ANSWER I'm high pressure
applications requiring saturated steam for heating or process work
Why are water tube boilers more cost effective in larger capacities - ANSWER The
shell on the steam drum is smaller and can be thinner
How often does the furnace walk of an oil fired boiler need to be cleaned? - ANSWER
Annually
What is the operating pressure range in a water tube boiler? - ANSWER Usually up
to 250psig
But in some cases 900psig
What equipment does the steam drum in a boiler contain? - ANSWER Feed water
distributor pipe, steam drum baffles, steam nozzles off the top of the drum, as well
as the holes for the tube attachments on the bottom portion of the drum
What is a cyclone separator - ANSWER An internal steam separator that uses
centrifugal force to remove the water from the steam-water
,What are steam main lines graded at? - ANSWER 1" per 20ft
Where is a stop valve placed on the boiler feed water piping? - ANSWER Between
the check valve and the boiler
How large must the feed water connection to the boiler be for 100sqft or less
heating surface? - ANSWER 1/2"
How large just the feed water connection to the boiler be for boilers with a
heating surface greater than 100sqft? - ANSWER 3/4"
How many full turns must a master valve on a blowdown line have? - ANSWER 5 full
turns
Why types of quick opening valves can be on a blowdown line? - ANSWER Gate or glove
valve
Order of valve opening on a blowdown line? - ANSWER Q, M, M, Q
How often are blow off systems in the mud drum operated? - ANSWER Intermittently
How often are blowdown systems in the steam drum operated? - ANSWER Continuously
TDS - ANSWER Total dissolved solids
Minimum blow off line size is 1" except where? - ANSWER Except on boilers having less
than 100sqft of heating surface, then it's 3/4"
, Maximum blow off line size? - ANSWER 2 1/2"
When must check valves be installed on blow off lines, where? - ANSWER When
there are 2 boiler blow offs connected to a common blow off header. Check valve
must be installed between header and downstream of blowdown valves
What is the maximum pressure design of a blowdown tank - ANSWER 30% of maximum
pressure up to 300psig
What temperature must effluent discharge to a draining system be? - ANSWER
Less than 75°C
What also acts as a flash steam vessel to cool condensate in the system? - ANSWER
Blowdown tank
How far up the blowdown tank does the blow off enter - ANSWER 3/4 of the way up
What is an attachment to the first nozzle or flange of a boiler called - ANSWER
Boiler trim
What does double block and bleed mean - ANSWER Bleed valve may be attached to
a nipple tee's into the pipe or may be tapped into the body of the block valve
Why are block and bleed valves used - ANSWER To prevent contaminating organisms
from entering the process
How many safety valves shall a boiler with more than 500sqft of heating surface be
equipped with? - ANSWER 2 or more
