Modern Refrigeration Chapter 52 WB
When leak testing a newly installed system using nitrogen, the pressure-relief valve should be adjusted to open ________ above the recommended testing pressure.
1 psi to 2 psi
For tubing runs that cross a room, the tubing must be at least ________ above floor level.
7'-3"
For a large, split commercial refrigeration system, a condensing unit should be _______ the conditioned space.
As close as possible to
When an evaporator is mounted vertically, the evaporator outlet should be located _______ the inlet.
Below
To hold mounting bolts in place until the motor is aligned and the washers and nuts are started on the bolts, some technicians use _________.
Caulking compound
In a multiple-evaporator system, a(n) _______ should be included between the suction line manifold and the outlet of the coldest evaporator.
Check Valve
A slip hazard is most likely to result from a __________ Joint that has not been properly sealed.
Condensate line
According to how the liquid receiver service valve shown was installed, the valve should be in the _______ position to top off the refrigerant charge with the compressor running.
Cracked open
When performing a hot pull down on a multiple-evaporator system by throttling the suction service valve (SSV), begin with the SSV so it is ______.
Cracked open
In a multiple-evaporator system, a(n) _______ should be include between the suction line manifold and the outlet of the warmest evaporator.
EPR (Evaporator Pressure Regulator)
On a multiple-evaporator refrigeration system, different temperatures are maintained in the different evaporators primarily because of the proper operation of ___________.
EPRs
The most important criteria used to determine filter-firer size for a commercial refrigeration system are the following, EXEPT for
EXEPT -Tubing size. (Compressor horsepower, Compressor operating cycle, type and quantity of refrigerant)
True or False. During low-side charging, the high-side valve on the gauge manifold should be kept open.
False
In commercial refrigeration systems, a sight glass should be installed between the __________.
Filter-drier and the metering device
The safety device that is designed to actuate in the case of a fire is a ______.
Fusible plug
When working with wiring, avoid connecting copper and aluminum, because this will most likely result in __________.
Galvanic corrosion
When an inspector or code enforcement officer issues a _______ tag, it means that the job is complete and approved by the code authority.
Green Tag
For larger commercial evaporators, __________ is often used as the condensate tubing.
Hard PVC
Commercial refrigeration systems must be tested under pressure on the _________ and be free of leaks.
High side and the low side
In a multiple-evaporator system, an accumulator is best installed _______.
In the main suction line near the compressor
For commercial refrigeration system, plumbing work must conform to code and be done by a(n)
Licensed Plumber
For commercial refrigeration systems, electrical work must conform to code and be done by a (n)
Licensed electrician
Most codes require that installation of commercial refrigeration equipment to be done by
Licensed refrigeration contractors
Standards for wiring and electrical equipment are most often covered by
NEC National electrical code
Two important principles of installation that help to minimize hazards are durability and
Neatness
When installing a new commercial system, a standing pressure test involves pressurizing the system with _________ and letting it stand for 24 hours.
Nitrogen
A condensing unit should be installed indoors and ________ .
None of the above answers.
Which position should the suction service valve be in during low-side charging?
None of the above. (Cracked open)
For each commercial refrigeration installation, a ___________ Must be obtained.
Permit
The safety device that is used to vent refrigerant only until high pressure is reduced is a
Pressure control
When an inspector or code enforcement officer issues a ______ tag, it means that work must stop until a plan to repair code violations is approved.
Red tag
When replacing a hermetic compressor, remember to ______ the joint after brazing tubing to the new compressor.
Remove any remaining flux from
The best way to prevent the overheating of a moisture indicator when brazing the joints of a sight glass is to ___________.
Remove the moisture indicator core
When setting aside unused tubing overnight, be sure to _________.
Secure plugs or caps over the ends
Hard-drawn ACR tubing should be supported by clams or brackets every _____ feet.
Six to eight feet
On a multiple-evaporator refrigeration system, a _______ should be included in each liquid line leading to each TXV.
Solenoid valve
The safety devise that is used to stop the compressor when excessively high head pressure developed is a
Spring loaded relief valve
If a leak is determined to be in a brazed joint, __________.
Take it apart, reassemble it, and braze it.
Standards for water and other non-refrigerant piping are often covered by
The IPC International plumbing code
True or False. A high ambient temperature causes a condensing unit to operate less efficiently.
True
True or False. Adding liquid refrigerant directly into the liquid receiver is best done with the compressor running.
True
True or False. HVACR technicians are permitted to connect and service low-voltage wiring.
True
True or False. Whenever possible, the inner parts of a valve should be removed while brazing the valve.
True
True or false. Due to the labor involved it is more time-consuming to install a split system than a package system.
True
The position of a TXV's sensing bulb on a suction line depends on the ________.
Tubing size
The first thing that a technician should do before turning on any newly installed open-drive motor is ______.
Turn it by hand to see if it will rotate freely
The type of hard-drawn ACR tubing used in commercial refrigeration systems is usually Type______.
Type K
To align and mark the proper placement of hangers for a wall-mounted or ceiling-mounted evaporator, ____________.
Use a cardboard template and a plumb line.
When performing a hot pull down on a multiple-evaporator system, it is most important to monitor the compressor motor's ________ to ensure that it is not being overworked.
Voltage
If a condensing unit is placed indoors, the room must be _________
Well ventilated
An effective way of ensuring that a TXV's sensing bulb is not affected by ambient air is to
Wrap the sensing bulb in insulation
When an inspector or code enforcement officer issues a _______ tag, it means that work may proceed, but certain items must be brought up to code.
Yellow tag
When performing a hot pull down on a multiple-evaporator system, it is best to start with _________.
one evaporator shutoff valve cracked open and all others closed.