South Carolina Boiler Installation Contractor Examination

Under ASME BPVC Section IV service restrictions, a heating boiler is limited to which combination of steam pressure, hot-water pressure, and hot-water temperature?

• A15 psi steam, 160 psi water, and 250°F water
• B15 psi steam, 100 psi water, and 210°F water
• C50 psi steam, 160 psi water, and 250°F water
• D30 psi steam, 200 psi water, and 300°F water

Per the 2021 International Mechanical Code, controls and safety devices for boilers shall meet ASME CSD-1 or NFPA 85 at which fuel-input breakpoint?

• AASME CSD-1 below 400,000 Btu/h and NFPA 85 at 400,000 Btu/h and above
• BASME CSD-1 below 5,000,000 Btu/h and NFPA 85 at 5,000,000 Btu/h and above
• CASME CSD-1 below 12,500,000 Btu/h and NFPA 85 at 12,500,000 Btu/h and above
• DASME CSD-1 for all packaged boilers and NFPA 85 only for field-erected watertube units

Unless otherwise approved, 2021 IMC working-clearance rules require passageways around all sides of a boiler to have an unobstructed width of not less than:

• A18 inches
• B24 inches
• C36 inches
• D12 inches

Under the 2021 IMC, how must a hot-water boiler be protected from overpressure?

• AWith a safety relief valve
• BWith an expansion tank only
• CWith a temperature-limit control only
• DWith a spring-pop steam safety valve set at 15 psi

Which 2021 IMC statement about expansion tanks on hot-water heating systems is correct?

• AAn expansion tank is required only when the boiler input exceeds 400,000 Btu/h
• BEach boiler in a multiple-boiler plant must have its own expansion tank
• CAn expansion tank shall be installed in every hot-water system, and multiple-boiler plant…
• DOpen-type tanks are prohibited; only ASME-stamped bladder tanks may be used

South Carolina’s Boiler Installation contractor classification may be obtained without the technical examination if a qualified individual of the company holds which credential?

• AAn ASME “U” stamp or a National Board “VR” stamp only
• BAn ASME “H” stamp or a manufacturer’s UL boiler listing
• CAn ASME “S” stamp or a National Board of Boiler and Pressure Vessel Inspectors “R” stamp
• DA current South Carolina master plumber license

Per 2021 IMC Table 1004.3.1, what is the minimum clearance from the top of a boiler that has a manhole on top to the ceiling or other overhead obstruction, unless a greater clearance in that table applies?

• A18 inches
• B2 feet
• C3 feet
• D7 feet

A high-pressure steam boiler has a steam-generating capacity of 6,200 pounds per hour. What minimum top clearance does 2021 IMC Table 1004.3.1 require from the top of the boiler to the ceiling?

• A2 feet
• B3 feet
• C5 feet
• D7 feet

Which 2021 IMC valve rule applies to boiler supply and return connections?

• AEvery boiler or modular boiler shall have a shutoff valve in the supply and return piping…
• BShutoff valves are prohibited on any steam boiler return
• COnly the supply connection needs a shutoff valve
• DMultiple boilers may share one pair of isolation valves on the common header

The 2021 IMC low-water-cutoff requirement for steam and hot-water boilers has which exception?

• AA low-water cutoff is not required for coil-type and water-tube-type boilers that require…
• BHot-water boilers under 1,000,000 Btu/h need no water-level or flow protection
• CA probe-type alarm may replace the cutoff on any packaged boiler
• DElectric boilers never require a low-water cutoff

A steam boiler has a maximum allowable working pressure of 125 psig. How must its bottom blowoff valves be arranged under the 2021 IMC?

• ATwo slow-opening valves in series, or one quick-opening valve and one slow-opening valve…
• BTwo quick-opening valves in parallel on a Y-base
• CA single slow-opening valve plus a check valve
• DOne quick-opening valve is sufficient at any pressure

Which installation detail is prohibited on 2021 IMC safety- and relief-valve discharge piping?

• AA rigid pipe no smaller than the valve outlet
• BA gravity, untrapped run that terminates not more than 6 inches above the floor
• CA valve or tee fitting in the discharge pipe
• DAn air break in the same room as the appliance (other than high-pressure steam)

An open-type expansion tank serving a hot-water heating system must be located not less than how far above the highest heating element, and what is the minimum overflow diameter?

• A4 feet above the highest heating element, with a 1-inch overflow
• B10 feet above the boiler, with a 2-inch overflow
• CLevel with the highest radiator, with no overflow required
• D2 feet above the boiler supply header, with a 1/2-inch overflow

A new fuel-gas piping system serving a boiler will operate at a maximum working pressure of 2 psig. What is the minimum IFGC pressure-test value?

• A3 psig
• B10 psig
• C1.5 psig
• D2 psig

What is the maximum overall length of an approved flexible gas appliance connector serving a boiler under the IFGC?

• A6 feet
• B10 feet
• C25 feet
• D3 feet

A boiler hydrostatic test will be run at 150 psi. Per 2021 IMC 1011.2, which indicating test-gage range is acceptable?

• A0 to 150 psi
• B0 to 200 psi
• C0 to 300 psi
• D0 to 1,000 psi

A boiler room contains gas-fired equipment totaling 800,000 Btu/h input. Combustion air is taken from outdoors through two permanent openings that communicate directly (or by vertical ducts) with the outdoors. What minimum free area is required for each opening?

• A80 square inches
• B160 square inches
• C200 square inches
• D400 square inches

A closed hydronic system contains 400 gallons of water, not including the expansion tank. Using 2021 IMC Table 1009.2, what is the minimum pressurized diaphragm-type expansion-tank capacity?

• A17 gallons
• B25 gallons
• C33 gallons
• D60 gallons

Fuel-gas piping serving a boiler will operate at 5 psig. What minimum IFGC test pressure must be used?

• A3 psig
• B5 psig
• C7.5 psig
• D15 psig

Yellow (non-arc-resistant) CSST gas piping serving a boiler plant must be bonded to the electrical-service grounding-electrode system with a copper bonding jumper not smaller than:

• A12 AWG
• B10 AWG
• C8 AWG
• D6 AWG

In a firetube heating boiler, where do the hot combustion gases travel relative to the boiler water?

• AThrough tubes that are surrounded by boiler water
• BThrough water-filled tubes that are surrounded by hot gases
• COnly across an external plate heat exchanger
• DDirectly through the steam drum without contacting heating surface

One boiler horsepower is defined as the evaporation of how many pounds of water from and at 212°F in one hour?

• A8.33 lb/h
• B15.0 lb/h
• C34.5 lb/h
• D33,475 lb/h

A Scotch marine boiler is best described as:

• AA cast-iron sectional watertube boiler
• BAn electric electrode boiler
• CA firetube boiler with one or more internal furnace (Morrison) tubes
• DA once-through coil steam generator

Each ASME Section IV steam heating boiler shall have one or more officially rated spring-pop safety valves identified with the V or HV symbol and adjusted to discharge at a pressure not exceeding:

• A15 psi
• B30 psi
• CThe boiler operating-control set point
• D10 psi

Why must a steam-boiler pressure gage be connected through a siphon (pigtail) or equivalent water seal?

• ATo develop and maintain a water seal that keeps steam out of the gage tube
• BTo allow the gage to be used as a low-water cutoff
• CTo vent noncondensable gases from the steam space
• DTo increase the indicated pressure by one atmosphere

Each automatically fired ASME Section IV steam heating boiler shall be protected from overpressure by how many pressure-operated controls, and what is the high-limit rule?

• ATwo pressure-operated controls; the safety limit shall cut off fuel to prevent pressure f…
• BThree controls, including a vacuum breaker
• CNo pressure controls if a 15 psi safety valve is installed
• DOne operating control set at 15 psi

In a watertube heating boiler, boiler water travels:

• AThrough tubes that are surrounded by hot combustion gases
• BThrough large firetubes inside a water-filled shell
• COnly in an external expansion tank
• DIn the chimney as water vapor mixed with flue gas

A packaged steam heating boiler is nameplated 50 boiler horsepower. Using 33,475 Btu/h per BHP, what is the equivalent heat output?

• A334,750 Btu/h
• B1,380,000 Btu/h
• C1,673,750 Btu/h
• D2,000,000 Btu/h

A 80-boiler-horsepower low-pressure steam boiler is rated from and at 212°F. What is its equivalent steam-generating rate?

• A800 lb/h
• B2,070 lb/h
• C2,760 lb/h
• D3,450 lb/h

Using the traditional heating-surface rule of 10 square feet per boiler horsepower, what is the equivalent rating of a firetube heating boiler with 400 square feet of heating surface?

• A10 BHP
• B34.5 BHP
• C40 BHP
• D400 BHP

A gas-fired firetube steam heating boiler has 300 square feet of heating surface. Using ASME Section IV Table HG-400.1, what is the minimum safety-valve relieving capacity based on heating surface?

• A1,500 lb/h
• B2,100 lb/h
• C2,400 lb/h
• D3,000 lb/h

A steam heating boiler has a maximum output of 2,500,000 Btu/h at the boiler nozzle. What is the minimum safety-valve capacity by the ASME IV maximum-output method?

• A250 lb/h
• B1,000 lb/h
• C2,500 lb/h
• D25,000 lb/h

ASME Section IV requires the dial of a steam heating-boiler pressure gage to be graduated to not less than which range?

• ANot less than 30 psi nor more than 60 psi
• BNot less than 60 psi nor more than 100 psi
• C0 to 200 psi
• D0 to 15 psi

Each automatically fired ASME Section IV hot-water heating or supply boiler shall be protected from over-temperature by:

• ATwo temperature-operated controls: a high-temperature limit that cannot be set above the…
• BA safety relief valve only
• CAn outdoor-reset control only
• DA single aquastat that both operates and limits the burner

On an automatically fired steam heating boiler, the low-water fuel cutoff shall cut off the fuel supply:

• ABefore the water surface falls below the lowest visible part of the water gage glass
• BOnly when the operating pressure control also trips
• CWhen stack temperature exceeds 400°F
• DAfter the gage glass has run completely dry for two minutes

Under ASME Section IV HG-614, an automatically fired hot-water boiler requires an automatic low-water fuel cutoff designed for hot-water service when heat input is greater than:

• A400,000 Btu/h
• B12,500,000 Btu/h
• CAny input; there is no size threshold in HG-614
• D120,000 Btu/h

What is the purpose of a Hartford loop on a gravity-return low-pressure steam heating system?

• ATo arrange the return so water in the boiler cannot be forced out below the safe water le…
• BTo replace the steam safety valve
• CTo provide combustion air to the burner
• DTo superheat the steam leaving the boiler

When a water column on a steam heating boiler is connected with pipe and fittings, ASME Section IV requires which installation detail?

• ANo shutoff valves of any type in the connecting pipe, and a cross or equivalent fitting a…
• BColumn connections not smaller than NPS 2
• CThe water connection taken from the top of the steam drum only
• DA gate valve in each column connection so the column can be isolated for service

On an ASME Section IV steam boiler, the lowest visible part of the water gage glass shall be at least:

• A1 inch above the lowest permissible water level recommended by the manufacturer
• B6 inches below the normal water line
• CAt the centerline of the boiler shell
• DLevel with the crown sheet or tubes

An electric steam heating boiler has an input of 160 kW. Using the ASME Section IV electric-boiler factor of 3½ lb/h per kW, what is the minimum safety-valve relieving capacity?

• A160 lb/h
• B480 lb/h
• C560 lb/h
• D1,600 lb/h

A hot-water heating boiler has a safety relief valve set at 30 psi. Per ASME HG-611, the mechanical pressure-gage dial shall be graduated to not less than 1.5 nor more than 3.5 times that set pressure. What is the acceptable full-scale window?

• A0 to 30 psi
• B0 to 40 psi
• C45 psi to 105 psi
• D0 to 200 psi

A low-pressure steam system has 1,200 square feet of Equivalent Direct Radiation (EDR). Using 240 Btu/h per square foot of steam EDR, what net boiler output is required?

• A144,000 Btu/h
• B216,000 Btu/h
• C288,000 Btu/h
• D360,000 Btu/h

A closed hot-water heating system has a calculated load of 600,000 Btu/h and is designed for a 20°F temperature drop. What flow rate is required?

• A30 GPM
• B48 GPM
• C60 GPM
• D120 GPM

With the burner at maximum firing rate, ASME Section IV requires that the pressure in a steam heating boiler cannot rise more than 5 psi above MAWP. If MAWP is 15 psi, what is the maximum permitted accumulation pressure, and what blowdown range is required of the safety valve?

• A20 psi accumulation and a controlled blowdown of 2 psi to 4 psi
• B22.5 psi accumulation and no specified blowdown
• C30 psi accumulation and 2 psi to 4 psi blowdown
• D16.5 psi accumulation and 10 percent blowdown

Which boiler falls under ASME BPVC Section I (Power Boilers) rather than Section IV?

• AA steam heating boiler operating at 12 psi
• BA hot-water heating boiler operating at 30 psi and 180°F
• CA steam boiler with an allowable working pressure of 100 psi
• DA hot-water supply boiler operating at 120 psi and 210°F

What is the function of a superheater on a high-pressure steam boiler?

• ATo condense exhaust steam for return to the boiler
• BTo remove dissolved solids by continuous blowdown
• CTo preheat feedwater with flue gas
• DTo add heat to steam after it leaves the steam drum, raising its temperature above satura…

An economizer on a high-pressure boiler is installed to:

• AReduce superheater outlet temperature
• BSeparate steam from water in the steam drum
• CPreheat combustion air with flue gas
• DPreheat feedwater with residual heat in the flue gas