Chapter 11
the size, capacity, and type of boiler determine the number and type of valves allowed by the ___ code
ASME
the surface blowdown line piping is located at the ___ of the boiler
NOWL
a condensate return system is a system used to return condensate back to the ___ after all the useful heat has been removed
boiler
a fuel oil ___ is a boiler component that provides atomized fuel oil to the boiler
burner
boilers that produce heat by combustion are made of steel or ____
cast iron
a flow ___ valve is a valve that regulates the flow of water in a hydronic heating system
central
the most common feed water pump is the ___ driven by an electric motor
centrifugal pump
a ___ gauge is a pressure gauge that indicates vacuum in inches of mercury and pressure in psi on the same gauge
compound
____ heating is heat transfer that occurs when currents circulate between warm and cool regions of a fluid
connection
a four-pipe piping system combines the return pipe for the heating and cooling system
false
a gate valve is a valve that allows flow in only one direction
false
a power steam boiler is a boiler in which steam or other vapor is used at pressures exceeding 15 psi but not exceeding 100 psi and having less than 440,000 Btu/hr heat input
false
a water column is a bent tube installed between the boiler and a boiler fitting to provide a water seal and prevent direct contact with steam
false
an air vent allows the water in a hydronic heating system to expand without raising the system water pressure to dangerous levels
false
coal-fired boilers are normally used for residential applications to millions of Btu/hr for commercial applications
false
gas cocks are normally located before the main gas valve, after the gas fuel train, and on the pilot light gas line
false
on small gas-fired boilers, the main gas valve is a fuel operated solenoid valve
false
the number of sections in a cast iron boiler determines the input rating of the boiler
false
the safety relief valve is the most important valve on a steam boiler
false
a ___ valve controls the flow of makeup water into a boiler to compensate for losses
feedwater
the ___ of a boiler contains the hot products of combustion and the waterside contains water
fire tube
a ___ boiler heats water that surrounds the fire tubes as the hot gases of combustion pass through the tubes
firetube
____ are components directly attached to a boiler and boiler devices that are required for the operation of the boiler
fittings
____ draft is mechanical draft created by air pushed through the firebox by blowers located on the front of the boiler
forced
a ____ is a warning device used to indicate extreme overheating of the boiler from a low water condition
fusible plug
a ___ valve is a metering valve that controls the volume of gas sent to a burner
gas butterfly
a ___ valve may be completely open, completely closed, or at any intermediate position in response to the control signal the valve receives
globe
on large boilers stet the main gas valves are ___ valves
hydraulic electric
the maximum amount of natural draft can be ____ with the height of the chimney
increased
____ draft is a mechanical draft created by air pulled through the boiler firebox by a blower located in the breaching after the boiler
induced
a ____ steam heating boiler is a boiler operated at pressures not to exceed 15 psi of steam
low pressure
a ___ valve allows steam to flow when the gate is lifted to the open position and the stem is up
ossy
a flow control valve is located on the ___ of a boiler
outlet piping
the more gas is heated, the faster it ____
rises
like a steam pressure gauge, the pressure control must be protected from live steam with a ___
siphon
gate valves and globe valves are used as ___ valves
step
a gauge glass is a tubular glass column that indicates the water level in the boiler
true
a hydronic heating system uses a boiler to heat water and store water
true
a pressure-temperature gauge is a gauge that measures the pressure and temperature of the water at the point on the boiler where the gauge is located
true
a steam fuel oil heater consists of a tube-and-shell heat exchanger with the steam being on the inside of the tubes
true
a terminal device is a heating system component that transfers heat from the hot water in a hydronic heating system to the air in building spaces
true
deadband is the setpoint differential when no heating or cooling is allowed because the temperature is between the two setpoints
true
during the operation of the boiler, there is a flow of air into the fuel, a flow of hot gases of combustion to the heating surface, and a flow of gases of combustion to the atmosphere
true
in a hydronic heating systems, a circulating pump moves the water through the supply piping system to the boiler and to the terminal devices
true
the amount of heat produced by a combustion boiler depends on the size of the boiler and the kind of fuel used
true
the pickup factor of a boiler can be as high as 30% to 50%
true
if the gauge glass is not functional, the second method for determining boiler water level is ___
try cocks
a ____ is a piping system that circulates the supply water in the opposite direction of the circulation of the return water
two-pipe direct-return piping system
a ____ is forced convection heater that has a blower, hot water coil, filters, controls, and a cabinet that has an opening for outdoor ventiliation
unit ventilator
return piping is connected to a centrifugal pump at the ___
water inlet
