Electrolux E32AR75FPS, Техническое и сервисное руководство

Страница: 58 / 112

5-14
Sealed System
To achieve the required 29.9 inch (500 micron) vacuum,
a properly maintained two-stage vacuum pump in good
condition is required. A two stage pump can reach a
deeper vacuum than a single stage because the exhaust
from the first pumping stage is discharged into the
second pumping stage. This means the second stage
begins pumping at a lower pressure so a lower ultimate
vacuum can be achieved.
Figure 5-5. Two Stage Vacuum Pump
Spills or Leaks
If a large release of vapor occurs, such as from a large
spill or leak, the vapors may concentrate near the floor
or low spots and displace the oxygen available for
breathing, causing suffocation.
Evacuate everyone until the area has been ventilated.
Use blowers or fans to circulate the air at floor level.
DO NOT re-enter the affected area unless you are
equipped with a self-contained breathing apparatus or
unless an area monitor indicates that the concentration
of HFC-134a vapors in the area is below the AEL.
Always use self-contained breathing apparatus or an
air-line mask when entering tanks or other areas where
vapors might exist. Use the buddy system and a life-
line. Refer to the Material Safety Data Sheet (MSDS) for
HFC-134a information.
HFC-134a vapors have a slightly sweet odor that can be
difficult to detect. Therefore, frequent leak checks and
the installation of permanent area monitors may be
necessary in enclosed spaces. Refer to ASHRAE
Standards 15 and 34 for refrigeration machinery rooms.
To ensure safety when working with HFC-134a in
enclosed areas:
1. Route relief and purge vent piping (if present)
outdoors, away from air intakes.
2. Make certain area is well ventilated, using
auxiliary ventilation if needed to move vapors.
3. Make sure area is clear of vapors prior to beginning
work.
4. Install air monitoring equipment to detect leaks.