Trane IntelliPak Installation, Operation And Maintenance Manual page 89

minutes or until the water temperature is greater than 35°F .
Once a water temperature of 35°F or greater is achieved,
the fill solenoid is energized, the sump will continue to fill,
and a five minute timer is started.
When the timer expires, the compressor lockout will be
released and mechanical cooling will be allowed. Head
pressure control will be regulated by a variable speed fan
until the liquid line pressure from either circuit reaches the
upper limit, which is set on the Human Interface under the
setup menu 120°F default.The liquid line pressure is
converted to a temperature for display at the Human
Interface. When the temperature exceeds the upper limit,
the condenser sump pump will be energized. When the
sump pump is energized, water is pumped from the sump
and sprayed over the condenser coil. If the liquid line
pressure from either circuit falls below the lower limit the
sump pump will be de-energized.
When the sump pump is energized or de-energized a
change in state is observed from an auxiliary contactor to
ensure proper sump pump operation. A change in states
must be observed by the auxiliary contactor within 6
seconds of the command to change states or mechanical
cooling will be locked out on a sump pump failure causing
a manual reset diagnostic to be set.
The fill solenoid will remain energized and the water level
will be controlled by the mechanical float valve. If the
maximum level float ever closes, an information-only
diagnostic is set and the fill solenoid is de-energized.This
is an indication that the mechanical float is not adjusted
properly or a failure of the mechanical float valve has
occurred. If the maximum level input is open for two
continuous minutes, the diagnostic will be cleared and the
fill solenoid will be energized.
If the sump water temperature ever drops below 35°F , the
drain actuator will be controlled in order to drain the water
from the sump. If there is a call for mechanical cooling and
the outdoor air temp is greater than 10°F on units with
sump heat installed or greater than 40°F on units without
sump heat, the unit will be allowed to refill the sump.
The drain control can be configured via the Human
Interface, and by the drain actuator installation, to hold or
drain water on power loss; the default is set to drain.
Periodic purge is a cyclic opening of the drain to remove
debris and buildup from the sump and add additional
fresh water to the sump. Periodic purge has an adjustable
interval from the setup menu on the Human Interface with
a range of 1-12 hours or can be set to disabled - the default
position if periodic purge is not required.The duration of
the blowdown, or the time that the drain valve is opened,
is adjustable to a range of 5 - 255 seconds, with 60 seconds
being the default.
The optional conductivity controller also uses this timer to
open the drain, when required, based on water quality.
During this purge, the fill solenoid will remain energized to
provide fresh water to the sump to replace water being
released during the blowdown. Water treatment
blowdown is provided by shorting the designated input on
RT-SVX36K-EN
the customer-supplied terminal strip.This gives the
customer more flexibility in determining water conditions
via external controls. Once the input is detected closed, the
drain valve will be opened for a time equal to the Human
Interface adjustable periodic purge duration.
Once the duration timer expires, or if the minimum level
switch opens, the drain valve will be closed and the water
treatment blowdown input will be ignored for 15 minutes.
During this blowdown the fill relay will remain open to
provide fresh water to the sump.The adjustable duration
time period should be set so that during drain operation 1
inch of water is drained from the sump with the fill
solenoid valve closed. If the minimum water level switch
opens during a blowdown cycle, the unit will de-energize
the sump pump in order to protect the compressors and
sump heater from insufficient water levels. Once the water
level reaches the minimum level input and this input
closes for 10 seconds, the compressors and sump heater
operations will be allowed to restart.
Evaporative Condenser Drain Valve Setup
The drain valve is shipped to "Drain During Unit Power
Loss Conditions. " This means that when the unit
disconnect is turned off, the 1S2 toggle switch is turned off,
or the unit loses power, the drain will open.The valve is
spring loaded and will travel from fully closed to fully open
in approximately 25 seconds.
This is desirable in cold climates where a risk of freezing
exists. In milder climates it may be desirable to keep the
water in the sump when unit power is off to avoid
unnecessarily wasting water whenever the unit
disconnect is turned off.
To convert the unit to "Hold During Unit Power Loss
Conditions":
1. Remove power from the unit.
2. Remove the weather shield cover
3. Loosen the shaft set screw
locking clip, and remove the shaft adapter
p. 90).
4. Lift the drain valve actuator and rotate it to the "hold
during power loss" position
5. Reinstall the shaft adapter and locking clip and reinstall
the actuator onto the base. Make sure the arrow on the
shaft adapter is set to 0°.
6. Make sure the valve is in the fully closed position, then
tighten the shaft set screw.
7. Reinstall the weather shield cover.
8. Restore power to the unit.
9. At the Human Interface, press SETUP , NEXT until 'Head
Pressure Control Setup Submenu" is seen. Press
ENTER.
10. Change the "Sump Drain Valve Relay Control" from
Drain to Hold
Unit Start Up
(Figure 55, p. 90).
(Figure 55), remove the
(Figure 56,
(Figure 58, p. 90).
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