Test questions

Stratosphere

-10-30 miles.

What is absolute zero?

-460F

Dial of a pressure gage, when the gage is permanently installed on the high side of a refrigerating system, shall be graduated to_______times the design pressure?

1.2

Refrigeration technician is good for:

10 Tons and up.

If (2) 500 Ohm stats are connected in series, resistance will be:

1000 Ohms

If (2) 500 Ohm resistors are wired in series, total resistance will be:

1000 Ohms.

A1 refrigerants over_______lbs l. Must be discharged to atmosphere

110

522CMR9.0 has adopted for a reference ASHRAE Standard:

15

Recovery cylinder

2 Parts - liquid/ vapor.

Pressure relief valves must discharge into atmosphere at least 15' above ground and_______from windows /ventilation openings.

20

One ton of refrigeration is removal of heat at:

200 BTU/MIN, 12,000 BTU/HR, 288,000 BTU/Day ALL OF THE ABOVE.

A single pole, double pole switch requires:

3 Wires

What is the electrical rating of 1 Watt of energy?

3.4 BTU/HR.

The total amount of refrigerant to be stored in a machinery room:

330 Ibs (ASHRAE) - 300 Ibs (Mass Code).

55. A rule of thumb in A/C is how many CFM/Ton?

400.

49. Liquid refrigerant 22 enters the evaporator at 50.2 PSIG/20 F and leaves at 38 F. It's pressure as it leaves will be:

50.2

Recovery cylinder

80% ONLY!

79. A chilled water pump suction gage reads 10 psig, discharge gage reads 48 psig. What is the head in feet of water the pump is working against?

88 ft. w.g. (1PSIG = 2.31 ft. hd) 38X2.31=88

High pressure controls should not be set higher than________% of the relief valves.

90

Liquid receivers shall not occupy more than_______% at 90 F.

90

Recovery cylinder

DOT approved.

A halide torch is most useful w/ a Freon compressor system to____________

Detect leaks in the piping joints

Oil separator is always inserted in the system in the:

Discharge Line

Clearance volume:

Effects compressor capacity.

Heat is a form of:

Energy

On cooling towers, what causes the condenser water temperature to drop?

Evaporation of the water droplets.

Two basic types of evaporators are:

Flooded & direct expansion feed.

Location of a low side and high side float (top/bottom)?

Flooded evaporator.

The boiling point of a refrigerant is governed by:

A temperature / pressure relationship.

If you have a clogged filter, what does motor do?

Amperage goes up, motor overheats.

The critical temperature of a refrigerant gas occurs when:

Any increase in pressure will not liquefy the gas.

By increasing superheat setting on a TXV will do what to frost line?

Get shorter.

A cascade system is:

Two or more refrigeration circuits (ANSI/ASHRAE P. 3).

How many closing forces operate a thermostatic expansion valve?

Two.

What type of copper tubing is NOT allowed in a refrigerating system?

Type M

Transformers are rated in:

Volt-Amperes.

9. Equation for Ohms Law:

Volts = Amps x Ohms

Formula for power in a resistance

W=VXA

27. Safety requirements are not enforced when_______is the primary refrigerant.

Water

Secondary refrigerants are usually:

Water or brine

Safety requirements are not enforced when________is the primary refrigerant.

Water.

1 degree rise / Ib. of water is known as:

BTU.

Where is a pressure limiting device located?

Between compressor and condenser.

A pressure limiting control shall be located:

Between compressor and stop valve.

Suction line is located:

Between evaporator and compressor.

When you start a walk in box at 90 F, what is designed to prevent liquid slugging to the compressor?

CPR Valve??

Suction valve unloaders afford effective means of:

Capacity control.

In a low pressure chiller, what type of compressor is used?

Centrifugal.

R-407C

Chocolate Brown

The oil separator is located between:

Compressor and Condenser.

A refrigerant turns into a liquid in the:

Condenser.

On a centrifugal compressor, the stationary diffuser vanes are used to:

Convert velocity energy to pressure.

What type of metals is not suited for ammonia systems?

Copper.

1. Thermodynamics is the division of science that deals with:

Heat Energy

A pressure limiting device is:

High Pressure Control

In a walk in cooler, when temperature is lowered, what happens to humidity?

Higher relative humidity

What would be considered an institutional occupancy?

Hospital.

What would be considered a residential occupancy?

Hotel.

Humidity can be sensed with:

Human hair

Which of the following controllers are most sensitive to temperature change?

Immersion Controller

The purpose of the receiver is:

Increase the capacity that a system can hold.

R-22 Chlorodifluromethane

Light Green

R-123 DichlorotrifluorETHANE

Light Grey

R-134a TetrafluoroETHANE

Light/Sky Blue

R-134A

Light/Sky Bluen

Solenoid valve in pumpdown control system would be located in:

Liquid Line

Booster compressors connect to the_______side of the system compressor.

Low Side

When a compressor is used as a booster side of another system, the booster provide that a low pressure stage compressor of the positive displacement type is protected by a compressor is considered on the_______ side of the system, to obtain a low pressure and discharges into the suction pressure relief device.

Low.

A device for measuring small pressure differences is the_________

Manometer.

July 1, 1992

No venting CFC & HCFC.

November 15, 1995 -

No venting HFC's.

Resistance is measured in:

Ohms.

How many forces operate a thermostatic expansion valve?

One opening, Two closing.

How many opening forces operate a thermostatic expansion valve?

One.

R-11 Trichlorofluoromethane

Orange

R-404A

Orange

R-502 R-22+R-115-Charge as vapor or liquid Does na

Orchid

Compressor in which increase pressure achieved by changing internal volume of compressor chamber:

Positive Displacement Compressor Wrong: Non-positive displacement compressor, Compressor pressure limiting device, Pressure imposing device.

In the early 90's, what was the most common refrigerant used?

R-22.

A tachometer is an instrument used to measure:

RPM

21. The refrigerant storage tank that holds a surplus of refrigerant & is located below the condenser is called the:

Receiver

30. Liquid and suction line heat exchangers are used for:

Reducing flash gas (subcools).

Stop valves shall not be permitted between the system and the:

Relief valves

R-410a R-32+R-125 - Charge as liquid only- fracionates

Rose/Pink

If a condenser is on a roof and the temperature is 35 degrees and falling, the capacity will:

Run as designed assuming low ambient controls.

A liquid used for transmission of heat without a change in state or no flash point or flash point above 150F is:

Secondary coolant

Pressure Relief Valves shall be marked w/ data from:

Section VIII Division 1 of the ASME Boiler & Pressure Code

Thermometer placed in discharge air supply. This is reading:

Sensible Heat

If a thermometer is placed at the outlet of the compressor, it will measure only_______ heat.

Sensible.

R-717

Silver

How is the oil pressure adjusted on an ammonia compressor?

Spring Pressure.

Ammonia compressors uses__________to adjust oil pressure.

Spring pressure.

Flusible plugs are marked in:

Temperature

Recovery cylinder

Tested / stamped every 5 years.

Pressure limiting control shall be connected between:

The compressor & stop valve on the discharge side.

ntue0? What would be considered a public assembly occupancy?

Theatre.

When the compressor is below the condenser:

Traps are needed on the discharge line.

R-12 Dichlorodifluromethane

White

Recovery cylinder

yellow top/gray bottom.