Seasonal Unit Start-Up; Daily Unit Shut-Down; Seasonal Unit Shut-Down - Trane CVHE Installation, Operation And Maintenance Manual

S S t t a a r r t t - - u u p p a a n n d d S S h h u u t t - - d d o o w w n n
flow is proven. Next, the control panel checks the
leaving evaporator water temperature and compares it
to the chilled water setpoint. If the difference between
these values is less than the start differential setpoint,
cooling is not needed.
If the control panel determines that the difference
between the evaporator leaving water temperature and
chilled water setpoint exceeds the start differential
setpoint, the unit enters the initiate Start Mode and the
oil refrigerant pump and the condenser water pump
are started. If flow is not initially established within
4 minutes 15 seconds of the condenser pump relay
energization, an automatically resetting diagnostic
"Condenser Water Flow Overdue" shall be generated,
which terminates the prestart mode and de-energizes
the condenser water pump relay. This diagnostic is
automatically reset if flow is established at any later
time.
N N o o t t e e : : This diagnostic does NOT automatically reset if
Tracer ® AdaptiView ™ is in control of the
condenser pump through its condenser pump
relay, since it is commanded off at the time of
the diagnostic. It may reset and allow normal
chiller operation if the pump was controlled from
some external source.
When less than 5 seconds remain on the restart inhibit,
the pre-start starter test is conducted on wye-delta
starters. If faults are detected, the unit's compressor
will not start and a diagnostic will be generated. If the
compressor motor starts and accelerates successfully,
Running appears on the display. If the purge is set to
AUTO, the purge will start running and will run as long
as the chiller is running.
N N o o t t e e : : If a manual reset diagnostic condition is detected
during start-up, unit operation will be locked out
and a manual reset is required before the start-
up sequence can begin again. If the fault
condition has not cleared, the control panel will
not permit restart.
When the cooling requirement is satisfied, the control
panel originates a Shutting down signal. The inlet
guide vanes are driven closed for 50 seconds, the
compressor stops, and the unit enters a 3-minute post-
lube period. The evaporator pump may continue to run
for the amount of time set using Tracer® AdaptiView™.
After the post-lube cycle is done, the unit returns to
auto mode.

Seasonal Unit Start-up

1. Close all drain valves, and reinstall the drain plugs
in the evaporator and condenser headers.
2. Service the auxiliary equipment according to the
start-up and maintenance instructions provided by
the respective equipment manufacturers.
82
3. Fill and vent the cooling tower, if used, as well as
the condenser and piping. At this point, all air must
be removed from the system (including each pass).
Then, close the vents in the condenser waterboxes.
4. Open all of the valves in the evaporator chilled
water circuit.
5. If the evaporator was previously drained, fill and
vent the evaporator and chilled water circuit. After
all air is removed from the system (including each
pass), close the vent valves in the evaporator
waterboxes.
6. Lubricate the external vane control linkage as
needed.
7. Check the adjustment and operation of each safety
and operating control.
8. Close all disconnect switches.
9. Perform instructions listed in
up," p. 81.

Daily Unit Shut-down

N N o o t t e e : : Also refer to Figure 53, p.
1. Press STOP.
2. After compressor and water pumps shut down, the
operator may turn Pump Contactors to OFF or open
pump disconnects.

Seasonal Unit Shut-down

I I m m p p o o r r t t a a n n t t : : Control power disconnect switch must
remain closed to allow oil sump heater
operation. Failure to do this will allow
refrigerant to condense in the oil pump.
1. Open all disconnect switches except the control
power disconnect switch.
2. Drain the condenser piping and cooling tower, if
used. Rinse with clean water.
3. Remove the drain and vent plugs from the
condenser headers to drain the condenser. Air-dry
bundle of residual water.
4. Once the unit is secured for the season, the
maintenance procedures described
and Table 23, p. 85 should be performed by
qualified Trane service technicians.
N N o o t t e e : : During extended shut-down periods, be sure to
operate the purge unit for a two-hour period
every two weeks. This will prevent the
accumulation of air and non-condensables in the
machine. To start the purge, change the purge
mode to ON in the unit control "Settings Purge"
menu. Remember to turn the purge mode to
"Adaptive" after the two-hour run time.
"Daily Unit Start-
74.
Table 22, p. 84
CVHE-SVX02M-EN