Unit 22 - Chapter 97

Question 0

In a gravity return system the boiler should be placed

Answer 0

Well below the lowest radiator

Question 1

The piping and heating units of a steam heating system must be so arranged that

Answer 1

Steam can flow freely to all heating units

Question 2

The Hartford loop prevents water in the boiler from

Answer 2

Dropping below a safe level

Question 3

All supply and drain lines of a steam heating system must be pitched to

Answer 3

Allow for drainage of condensate

Question 4

When starting up a steam heating boiler it should be filled to

Answer 4

1/2 of a gage glass

Question 5

If the water level falls too low during operation of a steam heating boiler the operator should

Answer 5

Shut the boiler down

Question 6

In the case of radiators and convectors, the main sources of trouble are the

Answer 6

Valves and traps

Question 7

Finned convectors should be kept free of

Answer 7

Dust

Question 8

Slow or insufficient heat throughout a building heated by steam can be caused by

Answer 8

Too low a firing rate

Question 9

Slow or insufficient heat in one or more rooms in a steam heated building can be caused by a

Answer 9

Faulty steam trap

Question 10

A pressure balancing device that prevents the boiler pressure from forcing the water in the boiler into the return line is called a

Answer 10

Hartford loop

Question 11

Steam in a two pipe, vacuum return system is supplied at a maximum pressure of

Answer 11

103 kPa

Question 12

A vacuum pump maintains a vacuum ___ kPa higher in the condensate return system than in the supply main

Answer 12

7 to 10

Question 13

Causes of insufficient steam supply to the heating units can be attributed to

Answer 13

• improper pitch
• defective radiator valve
• clogging of connections and valve

Question 14

In all systems, the horizontal steam supply pipes between boiler and heating units are called

Answer 14

Mains

Question 15

After a steam heating system has been operating for some time, you notice that some parts of the heating system are still cold. Which one of the following could be the cause of this?

Answer 15

Air is trapped in the affected sections

Question 16

The ___ system overcomes the difficulty of returning condensate back to the boiler due to insufficient static head.

Answer 16

Two pipe return trap system

Question 17

The two pipe gravity return heating system had the disadvantage that during startup, some steam could pass through a radiator without condensing and could enter other radiators via the return main, thus trapping

Answer 17

Air in the center

Question 18

In the two pipe vacuum steam heating system, the steam temperature can be varied from

Answer 18

105’C to 55’C

Question 19

The piping and heating units of a steam heating system must be so arranged that

Answer 19

Air can be expelled for the heating units and piping

Question 20

When a single main is used to carry both the steam supply from the boiler to the radiators and the steam condensate from the radiators back to the boiler the system is called

Answer 20

The one pipe gravity return system

Question 21

Which of the following would you not find in a steam heating system?

Answer 21

A cushion tank

Question 22

When the return main of a gravity return system is located below the level of the water line in the boiler it is called

Answer 22

Wet return