Super Combo

Réussis tes devoirs et examens dès maintenant avec Quizwiz!

When using recovery or recycling equipment that was made after 11-15-93 you must evacute a system containing MORE than 200 pounds of CFC-12 to ________ before making a major repair.

15 inches of HG vacuum

When using any solvent, chemical, cleaner, chemical or refrigerant you should review

MSDS (data sheets)

Atmospheric pressure

Our atmosphere extends abut 50 miles above the earth and consists of 78% nitrogen. 21& oxygen, the remaining one percent is composed of other gases.

For what refrigerant is an equipment room refrigerant monitor required under ASHRAE standard 15?

R-123

HCFC

R-22 R-123 R-124

Disposable refrigerant containers are used for ______ refrigerent

Virgin

Recycling and recovery equipment maufactured after 11-15-93 does not need an oil separator

...

A ternary refrigerant blend is a ____ part mixture

3

high pressure refrigerant

410a

To change the compressor on a system cantaining 40 pounds R-500 using a recycling machine that was manufactured AFTER 11-15-93 you must isolate the compressor then:

evacuate the isolated section of the system to 10 inches of vacuum and hold. If the system pressure does not rise, remove the compressor.

Long hoses between the unit & the recovery machine should not be used because they cause:

excessive pressure drop increased recovery time increased emissions

With an air-cooled condenser on the roof of a building and the evaporator on the first floor, recovery should first occur:

from the liquid line entering the evaporator

refrigerant that enters the compressor, under normal operating conditiona is a:

low pressure vapor

Systems charged with R410A should be leaked checked with?

pressurized nitrogen

Recovery Cylinder

yellow at the top gray at the bottom.

According to ASHRAE's 1992 refrigerant safety classification, which designations is the most safe

A-1

Non-Azeotropic refrigerants leak from a system

in uneven amounts due to different vapor pressures

defined as the force per unit area

pressure/vacuum.

When a new system has been assembled, the first thing to do is:

pressurize the system with inert gas and leak check

Heat pumps that have been retrofitted from R22 to R407C should be leak checked with:

pressurized nitrogen

Ozone layer

protects all life from the sun's harmful radiation

410a is a refrigerant for

pure on

A cyclinder with a grey body and yellow top is designed to hold:

recovered refrigerant

A compressor heater is used to:

reduce the amount of refrigerant in the lubricating oil

A system is dehydrated to:

remove water & water vapor

A system is dehydrated to:

remove water and water vapor

When operating refrigerant recovery or recycling equipment the following precautions should be taken

safety glasses & gloves along with following equipment safety precautions

System- dependent recovery equipment CANNOT be used when:

the appliance contains over 15 pounds of refrigerant

When evacuating a system the hoses should be:

equal to or larger than the vacuum pump inlet connection

When evacuating a system, the hoses should be:

equal to or larger than the vacuum pump inlet connection

When moisrture exists in an operating system which is likely to occur?

Acid will form

Which refrigerant has the highest ozone depletion potential

CFC's

To change the compressor on a system containing R-410A, you must isolate the compressor then:

Evacuate the isolated section of the system to atmospheric pressure and hold. If system pressure does not rise, remove the compressor.

Which refrigerant will not damage the stratospheric ozone

HFC

R-134a is a

HFC refrigerant

When dehydrating a system, the system can be heated to:

decrease the dehydrating time

clean air act

(EPA) regulates section 608 of the federal clean air act. Failure to comply could cost you and your company as much as $27,500. per day, per violation and there is a bounty of up to $10,000 to lure your competitors

Refrigerant leaves the condenser of an operating system as a:

high pressure liquid

The high pressure guage on service manifold sets has a contiuous scale, usall calibrated to read from:

0-500 psi.

ozone molecule

3 oxygen bonding together. Exist in a layer in the stratosphere in 10 to 30 miles above sea level.

When charging an R-12 refrigeration system that uses a water cooled condensor, you must first charge with vapor to a pressure of at least _____ , before switching to a liquid charging.

35 psig

EPA regulations require that leaking commercial or industrial process refrigeration equipment must be repaired when the leak rate exceeds______ of the charge per year.

35%

When using recovery or recycling equipment that was made BEFORE 11-15-93 technicians must evacuate a unit that has a normal charge of 10 pounds of CFC-500 to _____ before disposing of the system.

4 inches of HG vacuum

R-410A requires recovery tanks rated for at least:

400 psig

Reusable refrigerant containers that are normally under pressure above 15 psig, must be hydrostatically tested and date stamped every:

5 years

three types of refrigerants

CFC, HCFC, HFC.

the highest ozone depletion potential

CFC, and HCFC

Chloro floro carbon contains

Carbon, Chlorine , Florine , Hydrogen- green

4 things ultra violet light

Causes skin cancer, eye diseases, Reduction in crop fields, Affects small organism in the water

When using nitrogen to pressurize a system, you should always:

Charge through a pressure regulator

Compound gauge

Compound gauges that are used to measure low side pressure in air conditioning system can measure pressure both above below 0 psig.

Which refrigerant will not damage the stratospheric zone

HFC's

what type of refrigerant is clorine free

HFC's

CFC

Is released from the AC in the car from the refrigeration cycle and takes many years to travel to the stratosphere.

______ is the process of removing refrigerant in any condition from storing it in an external container without necessary testing or processing it in any way

Recovering

_______ refers to the process of cleaning refrigerant by oil seperation 7 single or multiple passes through filter driers which reduce moisture and acidity?

Recycling

it is necessary to place a refrigerant label on:

a frigerant cylinder that is being returned for reclaiming

Use _______ to remove ice from a sight glass

alcohol spray

In genreal blended refrigerants should be charged:

as a liquid

To obtain accurate vacuum readings during system evacuation, the system vacuum guage should be located:

as far from the vacuum pump as possible

Mercury barometer

atmospheric pressure will support a column of mercury 29.2 inches in the sealed tube

DOT requires youdo this when transporting cylinders

attach DOT classification tags

Prior to replacing the condenser coil in a high pressure system, the refrigerant was recovered and stored in a refillable container. The refrigerant:

can probably be charged back into the system

After refrigerant liquid has been recovered from a system, any remaining vapor is:

condensed by the recovery system

The evacuation of a system is a method of:

dehydration

A reciprocating compressor should not be energized if the

discharge service valve has closed

HCFC's

do not contain chlorine and have no ozone depletion potential.

The over-evacuation of a system:

does not occur

Which gas causes the least damage to the enviroment during a leak check?

dry nitrogen

The type of oil that is most commonly used in stationary refrigertion applications with HFC-134a refrigerant is:

ester oil

When a unit is opened for servicing the ______ should always be replaced

filter drier

The backseating of a suction shutoff valvee will close the:

guage port

Ozone depletion potential (ODP)

is a measurement of CFC's and HCFC's ability to destroy ozone

Reclaim

is the process that returns refrigerant to the new-product specifications and that requires chemical analysis.

It is illegal to

knowingly release refrigerant during the service, maintenance, repair or disposal of appliances with the exception of de minimis releases

A system can be evacuated to only atmospheric pressure when:

leaks in the appliance make the evacuation to the prescribed level unattainable

to recover liquid refrigerant you must connect one hose to the

liquid line

After refrigerant liquid transfer between recovery unit & the system being emptied ou need to avoid trapping:

liquid refrigerant between service valves

The primary water source for cooling the condenser of a water-cooled recovery unit is:

local municipal water supply

You can determine a safe pressure for leak testing a system from the:

low side test-pressure data-plate valve

When using recovery unit the fill level of the recovery tank can be controlled by

mechanical float switch electronic shutt-off device weight

the recovery of refrigerant from a system as a vapor only will minimize the loss of:

oil

When dealing with small systems, how many refrigerants may be recovered into the same cylinder?

one

When using nitrogen to pressurize a system you should:

only charge with nitrogen vapor

When evacuating a system the hoses should be:

short in length & as large in diameter as possible

Refrigerant that has been recovered can be returned to:

the same system or other systems owned by the same person without restriction

What factor affects the speed of evacuation?

the size of the equipment the ambient temperature the amount of moisture in the system

Measuring the system's final vacuum is always done with

the system isolated & the vacuum pump off

When a system will not hold a vacuum after it has been evacuated then:

the system may be leaking

When a systemwill not hold a vacuum after it has been evauated, then:

the system may be leaking

While R-410A is a high pressure refrigerant, it can be stored in the back of your service van as long as:

the temperature inside the vehicle does not exceed 125 degrees F. This is the same guidance given for R-22 and other common refrigerants.

A system is considered dehydrated when:

the vacuum indicator shows you have reached & held the required finished vacuum

Whenever dry nitrogen from a portable cyclinder is connected to a system, what item is of most importance to consider for safety?

there is a relief valve in the downstream line from the pressure regulator

Refrigerant vapors or mist should not be inhaled because

they may cause heart irregularities & or unconsciousness

ozone

three oxygen atoms bonded together.

R134

used In our newer refrigerant and cars

R22

used in residential and commercial applications

Moisture is removed a system by:

using a filter drier

Never use oxygen or compressed air to pressurize a sytem because:

when mixed with compresser oil or some refrigerants it could explode

The color code for refrigerant recovery cylinders is

yellow tops with grey bodies


Ensembles d'études connexes

AWS Academy Cloud Architecting [2606] - Module 13 Knowledge Check

View Set

Radio Frequency Fundamentals (560-15-2)

View Set

4.3: Week 3 of Tools of the Trade (Linux Command Line)

View Set

Programming the World Wide Web - Chapter 1

View Set

Module 15: Weight Status, Fitness, and Motor Competence

View Set

Chapter 20 Fill in the Blank Part A+B

View Set