Hydronics & Science Day 2 Flashcards

A complete set of practice questions and answers regarding hydronic and steam heating systems, fluid science, and pump specifications based on the lecture material.

Why are Hydronic heating systems noted for their cleanliness?

They are a closed system

What should compression tanks in a forced flow hot water system contain?

Water and air

What is the name of the device used to raise the temperature of steam on a boiler by raising its pressure?

Super heater

What is designed to protect boilers against loss of water?

Hartford Loop

From where does an economizer heat exchanger recover heat?

Hot flue gas

What is the correct condensate head height in a steam system required to return condensate to the boiler system?

$$28\,inches$$

In a gravity heating system, how is circulation to the heating units accomplished?

By the difference in the weight of the water in supply and return risers

What does a closed Hydronic heating system allow for?

Higher water temperatures

What is the name of the piping in a steam heating system that is filled with condensate and water and is below the water line of the boiler?

Wet return

How much static head pressure is created per foot of water?

$$0.433 \times \text{height}$$

How is pressure defined in a hydronic system?

Force per unit area

What is the specific heat of water?

$$1$$

What is considered the most practical and economical heat transfer medium?

Water

What is the common function of all steam traps?

Remove air and condensate

Which type of reducer should be used for a horizontal line on a steam main?

Eccentric reducer flat side down

What is the name for the upward force that liquid exerts on a body submerged in it?

Buoyancy

What are circulating pumps characterized as having $1/2\,h.p.$ motors or less and operating below $12\,feet$ of pressure head?

Low head pump

What is the heat required to change ice into water without an increase in temperature called?

Latent heat

What is the amount of heat required to raise the temperature of $1\,lb.$ of any substance called?

Specific heat

Evaporation is considered a form of what type of process?

Cooling process

What is it known as when air is saturated without changing the total heat?

Adiabatic temperature

What should be installed at each heating unit and at the end of a supply main?

Air vent

How many B.T.U. does it take to raise $5\,lbs.$ of water $1\,degree\,f.$?

$$5$$

What conditions may cause a pump to become starved?

Partial vacuum on pump suction, lack of suction lift, and a clogged strainer

What substances flow through the supply loop of a steam main?

Air, steam, and condensate

What are the primary ways of transferring heat?

Radiation, Convection, and Conduction

What is the name of the device used to raise the condensate a distance in a vacuum heating system?

Lift fitting

How many cubic feet at atmospheric pressure will a pound of steam occupy?

$$26.8\,cu.\,f.t.$$

What is atmospheric pressure at sea level?

$$14.7\,psia$$

What piece of equipment should be located at the low point of the return and closest to the steam boiler?

Condensate pump

What is the weight of $1\,gallon$ of water?

$$8.33\,pounds$$

What should be used to prevent water hammer in a steam system?

Steam trap

How long should the straight run of pipe be on the suction side of a pump to ensure good entry conditions?

$$5 \times \text{diameter of the suction pipe}$$

What piece of equipment can be used instead of a long straight run of pipe on the suction side of a pump?

Suction diffuser

In a hot water heating system, an expansion tank is located at least how far above the high point?

$$3\,feet$$

A valve marked $200 \text{ WOG}$ can be used on which systems?

Water, oil, and gas

Can water boil at $150\,degree\,f.$?

True

How are relief valves set?

According to the relieving capacity of the valve

At what pressure should a pressure relief valve close if it opens at $15\,psi$?

$$12\,psi$$

What is a high head pump?

Circulating pumps having $2\,h.p.$ motor or more and operating above $12\,feet$ of head pressure