Question 1

Which term means the lowest temperature at which fuel oil will flow as a liquid?&#10;A)pour point&#10;B)flow point&#10;C)flash point&#10;D)fire point

Accepted Answer

The pour point is the lowest temperature at which fuel oil remains fluid and can still flow.

Question 2

Which boiler control prevents a low-water condition from occurring?&#10;A)aquastat&#10;B)high limit control&#10;C)low-water fuel cut-off&#10;D)temperature-limiting control

Accepted Answer

The low-water fuel cut-off is a safety device that shuts off the fuel supply to the boiler if the water level drops below a safe operating level, preventing a low-water condition.

Question 3

Which of the following problems might air cause in a hydronic system?&#10;A)noise&#10;B)rust&#10;C)inhibited flow&#10;D)all of the above

Accepted Answer

Air in a hydronic system can cause noise, contribute to rust formation, and inhibit flow, making all the options correct.

Question 4

Where is a pressure relief valve installed in a hydronic system?&#10;A)within the top 6 inches of the boiler&#10;B)within the bottom 6 inches of the boiler&#10;C)at the highest point in the system&#10;D)at the lowest point in the system

Accepted Answer

A pressure relief valve is typically installed within the top 6 inches of the boiler to ensure it can effectively relieve excess pressure from the system.

Question 5

Which control is designed to remove air that is dissolved in water from a hydronic system?&#10;A)air vent&#10;B)expansion tank&#10;C)compression tank&#10;D)air separator

Accepted Answer

An air separator is specifically designed to remove air that is dissolved in water from a hydronic system.

Question 6

Where is the one location in the hydronic system where air is desirable?&#10;A)piping&#10;B)expansion tank&#10;C)boiler&#10;D)heating element

Accepted Answer

The expansion tank is designed to accommodate the expansion of water as it heats and to maintain system pressure. It contains a cushion of air that compresses as the water expands, making air desirable in this component.

Question 7

Which type of boiler is defined as one in which steam or other vapor is generated at a pressure of more than 15 psi?&#10;A)heating boiler&#10;B)power boiler&#10;C)high-pressure, high-temperature boiler&#10;D)hot water supply boiler

Accepted Answer

A power boiler is defined as one in which steam or other vapor is generated at a pressure of more than 15 psi.

Question 8

Which control is a back-up control designed to operate when other controls fail?&#10;A)high-limit control&#10;B)aquastat&#10;C)pressure relief valve&#10;D)low-water fuel cut-off

Accepted Answer

A high-limit control is a safety device that acts as a backup to prevent overheating by shutting down the system if the primary controls fail.

Question 9

Which of the following has an impact on the sizing of an expansion tank?&#10;A)system volume&#10;B)operating temperature&#10;C)pressure&#10;D)all of the above

Accepted Answer

The sizing of an expansion tank is influenced by system volume, operating temperature, and pressure, as all these factors affect the expansion and contraction of the fluid within the system.

Question 10

A dual-element, nonsimultaneous electric water heater has two 5,000-watt heating elements. What it its heat output in BTUs?&#10;A)13,648 BTUs&#10;B)15,355 BTUs&#10;C)17,060 BTUs&#10;D)18,766 BTUs

Accepted Answer

A 5,000-watt heating element produces 5,000 watts * 3.412 BTU/hr per watt = 17,060 BTUs/hr. Since the heater is nonsimultaneous, only one element operates at a time, so the heat output is 17,060 BTUs/hr.

Deck 6: Principles of Hydronic Systems