608 Type III

When charging a low-pressure system, refrigerant should be introduced to the system as a vapor to raise the system's saturation temperature to a minimum of;

36 degrees

When leak testing a low-pressure chiller, the maximum pressure to use is;

10 psig

A low-pressure chiller used for comfort cooling must be repaired if it has an annual leak rate of ____ of the total charge.

10%

To repair a chiller operating with R-22, the technician;

must have a Type II certification.

When pressurizing a low-pressure system for leak-detection purposes, do not exceed

10 psig

How long would an equipment owner or operator have to retrofit or retire an appliance that has exceeded the threshold leak rate if the replacement appliance uses 50 pounds or more of an exempt refrigerant?

18 months

After all the liquid has been removed from an average 350-ton, low-pressure appliance, approximately how much vapor refrigerant remains in the system?

100 pounds

Which of the following refrigerants has a safety classification of B-1

HCFC-123 (R-123)

What type of equipment can be worked on with Type III certification?

Low-pressure

If a strong odor is detected during the recovery process,

a compressor burn-out may have occurred.

Which organization establishes the refrigerant safety group standard?

ASHRAE

Where is the purge unit located in a low-pressure system?

Top of the condenser

Which of the following best describes the refrigerant recovery process from an R-123 system?

Start with liquid removal and then switch over to vapor recovery.

Because a low-pressure system operates below atmospheric pressure (in a vacuum),

leaks in gaskets or fittings will cause air and moisture to enter the system.

The Standard for machine room safety is;

ASHRAE-15

When installing more than one, pressure relief valves must be installed;

in parallel with each other.

The owner must keep records of refrigerant added to a low-pressure system during service and maintenance if the system charge is;

50 pounds or greater

What can be used to pressurize a chiller system before opening the system for a non-major repair?

Controlled hot water

Under ASHRAE Standard 34, R-134a is classified as;

A1

The EPA-required evacuation level for recovery or recycling equipment used on low-pressure systems is

25 mm of Hg absolute.

In a low-pressure chiller, air and other non-condensables collect at the;

top section of condenser

The most efficient method of leak checking a charged low-pressure refrigeration unit is to;

pressurize the system using controlled hot water or heater blankets.

During evacuation of systems with large amounts of water, it may be necessary to;

increase pressure by introducing nitrogen to counteract freezing.

The rupture disk on a low-pressure chiller has a burst pressure of;

15 psig

Where is refrigerant added to a low-pressure system during the charging process?

The lowest access point on the system such as the evaporator charging valve.