Cvhh-Svx001G-En - Trane CVHH CenTraVac Installation, Operation And Maintenance Manual

R R e e c c o o m m m m e e n n d d e e d d M M a a i i n n t t e e n n a a n n c c e e
3. Change the filter-drier assembly.
Inspecting the Moisture Indicator
Monitor the quality of the liquid refrigerant in the
chiller by periodically inspecting the moisture
indicator. The indicator will show "wet" whenever the
chiller moisture exceeds the levels shown in the
following table. Notice that the indicator becomes
more sensitive as the temperature decreases. (The
moisture indicator normally operates at equipment
room ambient temperatures.)
A "wet" indication for more than 72 hours typically
indicates that the filter-drier is saturated and should be
replaced. In some cases in which a substantial amount
of moisture has accumulated, such as when the chiller
has been serviced, several filter-drier assembly
changes may be required before a satisfactory
moisture level is achieved. A reoccurring or persistent
"wet" indication is a sign of possible chiller air or water
infiltration.
Inspect the moisture indicator only under the following
conditions:
• The chiller is operating.
• The purge unit is operating and has been allowed
sufficient time to properly remove system moisture
(allow a minimum of 72 hours after replacing filter-
drier).
Table 28. R-1233zd refrigerant moisture content as
determined by moisture indicator
75°F
Refrigerant
(23.9°C)
moisture level
Dry
Below 20
Caution 20–50
Wet Above 50
Note: Refrigerant moisture content given in parts per million (ppm).
Maintaining the Moisture-Indicating Sight
Glass
In normal operating conditions, the moisture-indicating
sight glass should not require maintenance beyond
keeping the sight glass clean. However, the sight glass
112
100°F 125°F
(37.8°C) (51.7°C)
Below 30 Below 35
30–80 35–100
Above 80 Above 100
should be replaced after any major repair to the unit
has taken place, or if it is on a unit in which severe
moisture contamination is known to have occurred.
Be aware that it is normal for the sight glass to indicate
the presence of moisture for a period of least 72 hours
after it is installed and after it has been exposed to
atmosphere. Allow a minimum of 72 hours after sight
glass installation or filter-drier service before using the
sight glass to determine the system moisture content.
Removing Air After Servicing the Chiller
Air that leaks into a chiller during servicing needs to be
removed so that the chiller can operate normally. The
purge pump-out system, which performs this function,
may operate for a long time to remove the air before
cycling off for the first time. This is due to the large
amount of non-condensables and the relatively small
amount of refrigerant being drawn into the purge tank.
I I m m p p o o r r t t a a n n t t : : Do NOT bypass or remove the pump-out
restrictor of the EarthWise ™ purge system.
Doing so could reduce the efficiency of the
purge system. The purge system has a
faster air exhaust rate than previous purge
systems, which makes bypassing or
removing the restrictor unnecessary.
The Daily Pumpout Limit determines how long the
purge pump-out compressor can operate continuously
without generating a Purge Daily Pumpout Exceeded
diagnostic, which will shut off the purge system. You
can disable the Daily Pumpout Limit to allow the purge
to pump out for an extended period of time.
After the level of non-condensables present in the
chiller falls to a point in which an increasing amount of
refrigerant enters the purge tank, the pump-out
compressor begins to cycle on and off. As the
refrigerant in the system becomes less contaminated
with non-condensables, purge pump-out is activated
less frequently.
N N o o t t e e : : If large amounts of non-condensables are
present in the chiller, the air removal rate can be
enhanced by operating the chiller at part-load
conditions.

CVHH-SVX001G-EN