Extra Material

Question 1

Red tin snips?

Answer 1

Right hand use and to cut straight or left

Question 2

Green tin snips?

Answer 2

Left hand use and to cut straight or right

Question 3

Yellow snips?

Answer 3

Straight cuts

Question 4

How is a lockout relay circuit wired?

Answer 4

Coil is in series with the contactor coil but parallel with the safety switches

Question 5

Fire extinguisher for combustible metals?

Answer 5

Class D

Question 6

What must be monitored in a confined space?

Answer 6

CO/O

Question 7

Journal bearing clearance?

Answer 7

1mil per inch of shaft diameter

Question 8

Crane

Raise boom?

Answer 8

Thumb up

Question 9

Crane

Lower boom?

Answer 9

Thumb down

Question 10

Crane

Hoist up/Down?

Answer 10

finger up and swirl = up

finger down and swirl = down

Question 11

Crane

Boom left and right?

Answer 11

Point left or right

Question 12

High traffic area?

Answer 12

Barricades and Flagger

Question 13

Heat anticipator is adjustable and wired in ______

Answer 13

series

Question 14

Cooling anticipator is wired in _________

Answer 14

Parallel

Question 15

CPR (CRO) is for protecting the compressor from overheating during ___________

Answer 15

hot pull downs

Question 16

General rule for adding refrigerant?

Answer 16

Follow manufacturer nameplate or 1/4oz per foot

Question 17

Briefly explain the push pull recovery method

Answer 17

Using vapour to push liquid out of the system

Question 18

When to use push-pull recovery?

Answer 18

10lb+ of refrigerant charge

Question 19

Explain the hose hook ups for push-pull recovery

Answer 19

Pull from vapour port of tank through recovery machine into vapour service port which drives liquid out of the liquid service port into the liquid port of the recovery tank

(Tank is upright)

Question 20

If your RTU blower is spinning backwards

a) reverse contactor leads
b) reverse disconnect leads

Answer 20

Reverse disconnect leads so the internal wiring stays OEM to the wiring diagram

Question 21

How many control wires in a carrier 48DD?

Answer 21

5

Question 22

What load runs continuously on carrier 48DD in heat or auto but not in cool?

Answer 22

inducer motor

Question 23

How to test concentration of brine solution?

Answer 23

hydrometer

Question 24

Carrier 48DD ______ shuts off immediately when call for heat ends

Answer 24

Blower

Question 25

Carrier 48DD forced draft relay is energized anytime the thermostat is in heat or cool? T or F

Answer 25

True

Question 26

Walk in cooler When using low pressure switch as temperature control, set the cut out ____ lower than desired box temp. Set cut in above freezing to accomplish off cycle defrost

Answer 26

15F

Question 27

Cut-out pressure = cut-in minus ________

Answer 27

differential

Question 28

What parts of an EEV may be serviced?

Answer 28

The valve body and pin

Question 29

Difference between high pressure and low pressure chillers?

Answer 29

Lower evaporator temperatures

Question 30

Low pressure chiller evaporators sometimes operate in a ______ which requires the use of ____-units to remove non-condensable

Answer 30

vacuum non-condensables

Question 31

Centrifugal compressor chillers use low-pressure refrigerants such as ______ to operate at below atmospheric pressures

Answer 31

R-123

Question 32

Screw compressor chillers have capacity up to

Answer 32

750tons

Question 33

How is capacity controlled for a screw compressor?

Answer 33

Slide valves to reduce down to 10%

Question 34

Capacity control for a centrifugal chiller?

Answer 34

Guide vanes at impeller eye

Question 35

Fall pro or safety cage needed for scaffolding over ___ high

Answer 35

16'

Question 36

Where would an EPR be used?

Answer 36

On an evaporator that requires a higher temperature than the rest

Question 37

Is an EPR a CRO or ORI?

Answer 37

ORI

Question 38

How to adjust an EPR?

Answer 38

access port on evaporator side and an adjustment screw on the top

Question 39

How to adjust an EEPR? electronically operated

Answer 39

Through an Energy management system or an Electronic control module

Question 40

Use a ____ pump to add oil to system while the compressor is operating

Answer 40

hand

Question 41

You can add oil by immersing a tube into a reservoir and using the compressor to draw oil into the crankcase. True or False?

Answer 41

True

Question 42

How to change oil on a compressor?

Answer 42

Drain from the drain plug and refill using a hand-pump

Question 43

What is a VAV?

Answer 43

Adjusts dampers based on heating/cooling needs from room thermostat

Question 44

Where is a VAV located?

Answer 44

Before the diffuser

Question 45

How is a VAV controlled?

Answer 45

Electrically or Pneumatically

Question 46

Some VAV's have terminal heaters inside? T or F

Answer 46

True

Question 47

Cooling towers lower the temperature of warm condenser water by about 10F and sends it back to the _______

Answer 47

condenser

Question 48

Is wet-bulb or dry-bulb more critical in cooling tower performance?

Answer 48

wet-bulb

Question 49

Describe blow-down in cooling towers?

Answer 49

Intentional drainage of water

Question 50

Describe drift in cooling towers?

Answer 50

Evaporated water (unintentional loss)

Question 51

Describe make-up water in cooling towers?

Answer 51

Float switch allows pump to refill what was lost

Question 52

How to increase contact between air and water in a cooling tower?

Answer 52

wet decks

Question 53

Describe an open loop cooling tower?

Answer 53

Condenser and cooling tower share the same water

Question 54

Describe closed loop cooling tower?

Answer 54

Condenser and cooling tower do not share the same water

Question 55

Cooling Tower Approach: ​ 1. Approach is the difference between the water leaving the tower and the entering wet bulb temp of the ____ 2. A 7F approach is common in HVAC systems with 78F entering wet bulb and 85F water leaving the _____ ​ (85F - 78F = 7F)

Answer 55

air water