Epa - Type 3 - Retail Ready

Front 1

How can ice be removed from a sight glass?

Back 1

Cleaned with an alcohol spray.

Front 2

How high should you pressurize an idle low pressure chiller to prevent air accumulation?

Back 2

Slightly above atmospheric pressure.

Front 3

What effect does air in a chiller have on head pressure?

Back 3

Raises head pressure.

Front 4

What system failures require taking and oil sample?

Back 4

A leak or major component failure (compressor burnout).

Front 5

Why must water be circulated through a chiller during refrigerant recovery?

Back 5

To prevent freeze-up of the water as pressure is reduced on the refrigerant.

Front 6

What is the lowest access valve on a low pressure chiller?

Back 6

The evaporator charging valve.

Front 7

Where is a centrifugal chiller's rupture disk attached?

Back 7

At the evaporator.

Front 8

What is the typical pressure setting for a low pressure chiller's rupture disk?

Back 8

15 PSIG.

Front 9

Where is the outlet of a rupture disk discharged?

Back 9

Outdoor for venting.

Front 10

How is a chiller typically charged?

Back 10

Liquid through the evaporator charging valve.

Front 11

What minimum saturation temperature needs to be achieved before liquid is charged into a chiller?

Back 11

Above freezing, typically 36 deg. F.

Front 12

To prevent freezing of water when charging a chiller, what pressure should be reached with vapor before using liquid CFC-11?

Back 12

16.9 inches of Hg.

Front 13

What could result from liquid refrigerant being charged into a chiller that is holding a 29 inch Hg. vacuum?

Back 13

Can cause system water to freeze.

Front 14

What function is served by a purge unit on a chiller?

Back 14

Minimize the effects of contamination. To remove non-condensables.

Front 15

What is the most likely cause of air leaks into a chiller refrigerant circuit?

Back 15

Gaskets and fittings.

Front 16

How is a purge unit connected on a low pressure chiller?

Back 16

The inlet of the purge unit is typically connected to the top of the condenser.

Front 17

Where is the suction of a purge unit connected?

Back 17

The inlet of the purge unit is typically connected to the top of the condenser.

Front 18

What is a high efficiency purge unit?

Back 18

It removes non-condensables that contain a low percentage of refrigerant. This adds to the value of the purge drum in refrigerant containment.

Front 19

Shaft seals on an open type compressor are susceptible to what failures?

Back 19

Refrigerant leaks.

Front 20

Purge units work best when they are not needed. How can purge unit operating time be reduced?

Back 20

By regular leak checking and repairing any leaks on a regular schedule.

Front 21

What is the maximum pressure that can be used when leak checking a low pressure chiller?

Back 21

10 PSIG on low pressure equipment that utilizes a rupture disk.

Front 22

What is the preferred method of leak checking a charged low pressure chiller?

Back 22

By increasing the refrigerant pressure using an external heat source or running hot water through the chiller tubes not to exceed 10 PSIG.

Front 23

Where should you check for leaks between a chiller refrigerant tube and the water box?

Back 23

The chiller barrel can be emptied of all water and a leak check can be made at the drain valve with the water off. If the tubes themselves require a leak check, the check can be made with a hydrostatic tube test kit.

Front 24

What is a hydrostatic tube test kit used for?

Back 24

To check for leaks in a chiller tubes.

Front 25

What leak rate is permissible on industrial and process refrigeration?

Back 25

Effective 6/14/93, any annualized leak rate of 35% or more on equipment with 50 lbs. of charge or more must be repaired. Less than 35% is permissible.

Front 26

What leak rate is permissible on equipment other than industrial and process equipment?

Back 26

For appliances with 50 lbs. of charge or more an annual leak rate of 15% or more must be repaired. Less than 15% leak rate is permissible.

Front 27

According to ASHRAE 3-1990, what rise is permitted in vacuum level during a standing vacuum test?

Back 27

Starting at 1mm of Hg., after 12 hours the vacuum reading should not increase to more than 2.5 mm of Hg.

Front 28

List two steps to reduce the run time of a purge unit.

Back 28

Regular leak checks and repair any leaks.

Front 29

Why should the water side of the evaporator and condenser be drained before recovering refrigerant from a chiller suspected of having tube leaks?

Back 29

To prevent moisture from being drawn into the refrigerant circuit.

Front 30

If a purge unit is operating excessively, what problem can you expect to find?

Back 30

Leaks.

Front 31

What condition would cause continuous excessive moisture collection in the purge unit of a low pressure refrigeration system?

Back 31

Leaks between the refrigerant circuit and the water circuit.

Front 32

Why should oil be warmed prior to removal from a low pressure chiller?

Back 32

To vaporize any liquid refrigerant that might be trapped in the oil.

Front 33

After liquid recovery, what must be done with the vapor still in the system?

Back 33

Vapor recovery must be performed.

Front 34

Is recovery of refrigerant from a low pressure appliance typically started with liquid or vapor?

Back 34

Start with liquid removal.

Front 35

Where is the connection made for the water supply used on a water cooled recovery unit?

Back 35

Local water supply.

Front 36

What should be the maximum pressure on the discharge of a recovery machine for low pressure systems?

Back 36

10 PSIG, because the rupture disk is set to open at 15 PSIG.

Front 37

What should be done with the water pumps during a recovery form a low pressure chiller?

Back 37

Turned On

Front 38

What is EPA's definition of a "major repair"?

Back 38

Any repair that involves the removal of the compressor, evaporator, condenser, or any auxiliary heat exchange coil.

Front 39

What recovery vacuum must be met on a low pressure appliance using a machine built in 1992?

Back 39

25 inches of Hg.

Front 40

Why should you wait a few minutes after reaching the required recovery vacuum on an appliance to see if pressure rises?

Back 40

To see if refrigerant is still trapped in the system.

Front 41

Under what circumstances may the recovery from an appliance be stopped without reaching the prescribed level?

Back 41

If the recovery would contaminate the refrigerant being recovered (this level cannot exceed 0 PSIG.)

Front 42

Is it a requirement that recycling and recovery equipment be capable of handling more than one refrigerant?

Back 42

No

Front 43

Is it permissible to warm the refrigerant under EPA's regulations to pressurize a low pressure system to do a non-major repair?

Back 43

Yes

Front 44

What final vacuum level is required for recovering refrigerant from a low pressure system if the technician is using recovery equipment manufactured BEFORE November 15, 1993? After November 15, 1993?

Back 44

25 inches of Hg, 25 mm of Hg. Absolute (equal to about 29 inches of Hg.)

Front 45

Are multiple relief valves connected in series or parallel?

Back 45

Parallel

Front 46

ASHRAE Standard 15 covers refrigerant level monitoring for what refrigerants?

Back 46

All

Front 47

According to ASHRAE Standard 15, what is the standard for refrigerant concentration for a machine room that must not be exceeded without activating an alarm and starting ventilation in the machine room?

Back 47

May not exceed the TLV-TWA. (Threshold limit value-Time weighted average.)

Front 48

List four safety procedures that should be followed when working with liquid low pressure refrigerant.

Back 48

1. Use refrigerant sensors in equipment room. 2. Avoid siphoning refrigerant by mouth. 3. Wear butyl-lined gloves. 4. Wear safety glasses.

Front 49

What is the toxicity and flammability rating of HCFC-123 per ASHRAE Standard 34?

Back 49

B1.