Hydronics

Question 1

T or F

A compression tank is not necessary in a system if a reducing valve is used?

Answer 1

F

Question 2

T or F

It is best to connect the make-up water line into the air line going to the compression tank?

Answer 2

T

Question 3

Why is the boiler chosen for air separation?

Answer 3

Due to the lower flow rates within the conventional boiler and because this is where the highest temp in the system occurs.

Question 4

What effect does static pressure have on pump capacity?

Answer 4

Static pressure in a closed system has no effect on pump capacity

Question 5

In what three ways does the human body lose heat?

Answer 5

Radiation
Conduction and convection
Evaporation

Question 6

What effects will become immediately apparent if air is allowed to leave the compression tank and get into the system?

Answer 6

A gravity circulation between the tank and the system will occur causing the tank temp to approach that of the system

Question 7

What is the maximum working pressure of the average hot water boiler?

Answer 7

160 psig
And 30 psig.
I’m gonna put both. If I see this question.

Question 8

Why may a hot water boiler designed for hot water, never be used for steam?

Answer 8

Hot water boilers are limited to a max working temperature of 250°f. It might not be able to handle the high pressure and temp required for a steam system.

Question 9

Define the term hydronics?

Answer 9

Hydronics is the heating and or cooling system that uses water and or another fluid as a heat transfer medium to move heat from one area to another.

Question 10

List five acceptable requirements for an ASME hot water relief valve.

Answer 10

The valve is constructed in accordance with ASME requirements

It must have a tag with the proper BTU-H rated capacity

The rated capacity should match match the gross output of boiler .

It must be properly installed at correct location.
The try lever provides a means of testing.

Question 11

Explain the operation of the reverse return system.

Answer 11

The first terminal unit taken off the supply main is the last to connect to the return main.

Question 12

What happens to the water in all hot water boilers as the temperature of the water increases?

Answer 12

It begins to expand as the temperature rises.

Question 13

What is one of the basic diff between the single main and two-pipe system?

Answer 13

The 2 pipe system has a separate supply and return main that can overcome higher pressure drops than what a diversion valve can handle.

Question 14

What is pressure drop?

Answer 14

Pressure drop is the amount of pressure lost between any two points in a system.

Question 15

What are the four basic components parts of a water chiller?

Answer 15

The compressor
The evaporator
The condenser
The refrigerant

Question 16

Describe the piping arrangement of a three pipe-system .

Answer 16

A hydronic heating and cooling system consisting of a hot supply main , and a common return main.

Question 17

What causes pressure drop?

Answer 17

The friction created between the inner walls of pipe and fittings and the liquid flowing through them.

Question 18

What is the term applied to the height to which the cooling tower pump must elevate water?

Answer 18

Static discharge head = the vertical distance the liquid is being pushed as measured from the center of the pump discharge to the point of open discharge.

Question 19

Where must the expansion tank be located in a gravity hot water system

Answer 19

At the highest point usually open to atmosphere.

Question 20

Why must air never be completely eliminated from the system?

Answer 20

It acts a cushion or compressed spring which allows for thermal expansion and equal pressure to all parts of the system.

Question 21

What is a good definition of comfort.

Answer 21

The condition in which the human body feels neither warm nor cool and is at thermal equilibrium with the ambient temperature.

Question 22

List three types of hydronic piping systems.

Answer 22

Two-Pipe System
Three-pipe systems
Four pipe systems

Question 23

What causes the water to circulate in a gravity hot water heating system.

Answer 23

The heated HTF will naturally rise within a large system; whn it cools from the loss of heat it will gravitate downward creating the natural circulation.

Question 24

What must be done to the piping leading from the boiler to the compression tank.

Answer 24

It must always be pitched up and be large enough in diameter to allow water and air to pass each other at the same time.

Question 25

Why should a mixing valve not be interchanged with a diverting valve?

Answer 25

It would short cycle your terminal units if the mixing valve is in the wrong spot.

Question 26

What may be done to reduce the size of a compression tank?

Answer 26

Place it as high as possible in the system.

Question 27

Mixing valve and pipe system drawings.

Answer 27

Question 28

Mixing valve and pipe system drawings

Question 29

Mixing valve and pipe system drawings

Answer 29

Question 30

Mixing valve and pipe system drawings

Answer 30

Question 31

Mixing valve and piping system drawing

Answer 31

Question 32

Mixing valve and piping drawings

Answer 32

Question 33

2 pipe parallel flow system drawing

And

2 pipe reverse return system drawing

Answer 33