Chapter 3 Flashcards
In a gravity return system, the boiler should be placed
A. well above the highest radiator
B. well below the lowest radiator
C. on an elevated platform
D. at the same level as the radiators
B
A pressure balancing device that prevents the boiler pressure from forcing the water in the boiler into the return line is called a
A. Pressure Equalizer
B. Bleed Vane
C. Hartford Loop
D. Pressure Control Valve
C
If the water level falls too low during operation of a steam heating boiler, the operator should
A. Lower the flame and add water to bring it up to a safe level
B. Add more water immediately
C. Operate the safety valve
D. Shut the boiler down
D
Steam in a 2-pipe vacuum return system is supplied at a maximum pressure of blank.
A. 75 kPa, [10 psi]
B. 50 kPa, [7 psi]
C. 200 kPa, [30 psi]
D. 103 kPa, [15 psi]
D
Causes of insufficient steam supply to the heating units can be attributed to
A. Improper pitch
B. Defective radiator valve
C. Clogging of connections and valves
D. All of the above
D
A method of closely controlling steam temperatures to match a varying heating load is:
a)Use of a return trap
b)Use of central humidifiers
c)A variable vacuum system
d)A pumped condensate system
c
In a pumped condensate return system, if condensate is not returned to the boiler as quickly as steam is being produced:
a)the Hartford loop will alarm
b)the boiler will flood
c)the boiler will take on make-up water
d)the float will stick
c
The “return trap system” was designed to address the difficulty of
a)low steam pressure in a two pipe system
b)low static head in a gravity return system
c)high condensate pressure
d)low condensate return in a pumped condensate system
b
The piping and heating units of a steam heating system must be arranged so that
a)Condensate can removed easily from these units and returned to the boiler
b)Steam can flow freely and in sufficient quantities to all heating units
c)Air can be expelled from the heating units and piping
d)All of the above
d
Horizontal steam supply pipes that extend between the boiler and the building’s heating units are called:
a)mains
b)risers
c)pipes
d)suppliers
a
The Hartfood Loop
a)Is typically found on a hot water heating boiler
b)Prevents back-feeding of the boiler water into the return line
c)Consists of a series of hygroscopic discs
d)Senses a reference pressure and compares it against a measured variable
b
The main sources of trouble with steam heating system radiators and convectors are:
a)Traps and valves
b)Pressure controllers
c)Corroded fittings
d)Air vents and diverter fittings
a
When steam supply mains are located below the heating units and the steam is supplied upwards through risers to the heating units, the system is called:
a)an upfeed system
b)a mains system
c)a two-pipe system
d)a risers system
a
