Chapter 4 Flashcards
The water temperature in a commercial application for a circulation system may be as high as blank.
A. 94°C, [201°F]
B. 75°C, [167°F]
C. 250°C, [482°F]
D. 100°C, [212°F]
A
Which of the following is an advantage for a hot water heating system compared to steam heating?
A. Minimum power requirement to circulate the water, especially in a large hot water heating system.
B. Lower maintenance costs with less corrosion concerns and no steam trap requirements.
C. Less damage to the heating system with the hot water leakage.
D. Air vents are not necessary because the system is completely filled with water in operation.
B
The heating coils in a snow melting system should be embedded at least blank below the concrete surface.
A. 2cm, [0.8 in.]
B. 10cm, [4 in.]
C. 7.5cm, [3 in.]
D. 5cm, [2 in.]
D
The most common type of piping system used in modern hot water heating is:
a)Two pipe direct return
b)One pipe
c)Two pipe reverse return
d)Series loop
c
A hot water heating system differs from a steam heating system in that:
a)Hot water systems use radiators and convectors
b)Hot water heating systems are intrinsically safe
c)The entire heating system including the piping and boiler is filled with water
d)Hot water heating systems are installed in commercial buildings
c
One important difference between the upfeed style hot water heating piping system and the downfeed style is that with the upfeed style the circulating pump is located on the top floor of the building
True False
false
The hot water heating system temperature difference from the boiler outlet through the system piping and back to the boiler return connection is typically:
a)20C (68F)
b)5C (41F)
c)11C (20F)
d)12 kPa (1.7 psi)
c
In a gravity hot water heating system the pipe sizing must be ________________ than in a pumped circulation system
a)Heavier wall thickness
b)Larger diameter
c)Suspended higher
d)Thinner wall thickness
b
A closed expansion tank in a hot water heating system:
a(Allows expansion and contraction of the water as its temperature changes
b)Reduces the need for diverter fittings
c)Eliminates the need for a circulating pump
d)Should be installed above the highest raditation element in the heating system
a
Heating rooms by means of warmed sections of ceilings, walls, or floor panels is considered to be:
a)Re-heating
b)Radiant panel heating
c)Impossible
d)Coil heating
b
A hydronic heating system is
a)A steam heating system
b)A vacuum heating system
c)A condensate heating system
d)A hot water heating system
d
An important advantage of hot water heating over steam heating is:
a)The Hartford Loop is much easier to pipe on a hot water boiler
b)The steam boiler’s circulating pump requires extra energy
c)The temperature of the heating water can be varied in relation to the changing outdoor temperature
d)A hot water boiler can withstand higher pressure than a steam boiler
c
The _______________________________ hot water heating system is difficult to balance because of the different circuit lengths to each convector
a)Two-pipe reverse return
b)Two-pipe direct return
c)Multi-storey upfeed
d)Split series loop
b
