Unit 21 - Chapter 94

Question 0

To prevent corrosion in the expansion tank it is sometimes filled with

Answer 0

Nitrogen

Question 1

Excessive pressure build up due to a rise in temperature and the resulting expansion of the water in the system is prevented by the use of

Answer 1

An expansion tank

Question 2

Improper location of circulating pump and expansion tank can cause

Answer 2

• the circulating pump to cavitation
• some points in the system to be under negative pressure
• air to be drawn into the system
• vapour bubbles to form in the circulating pump

Question 3

The expansion tank is normally attached to the

Answer 3

Boiler or hot water supply line near the boiler

Question 4

The minimum reading on an altitude gage of a boiler in a large plant is from the top of the boiler to the highest point in the system plus

Answer 4

1.2 m

Question 5

The purpose of a pressure reducing valve is to

Answer 5

Automatically reduce pressure and maintain it

Question 6

What type of boiler would you expect to find in a hot water system, incorporating a converter?

Answer 6

Steam boiler

Question 7

To regulate the flow of water to a zone circuit, a ___ is used.

Answer 7

Balancing valve

Question 8

The purpose of a pressure reducing valve is to automatically reduce pressure and

Answer 8

Maintain it

Question 9

For hot water heating systems in small buildings, the min operating pressure should be

Answer 9

83 kPa

Question 10

What chemical is not used in the cleaning of hot water systems?

Answer 10

Trisodium phosphate

Question 11

The normal type of circulating pump used in hot water heating systems is a

Answer 11

Single stage centrifugal