Trane IntelliPak 2 Series, Installation, Operation And Maintenance Manual

Page: 94 / 220

94 RT-SVX24Q-EN
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 120 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 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,” complete the following steps:
1. Remove power from the unit.
2. Remove the weather shield cover ( Figure 64, p. 94 ).
3. Loosen the shaft set screw ( Figure 64, p. 94 ),
remove the locking clip and remove the shaft
adapter (
Figure 65, p. 95 ).
4. Lift the drain valve actuator and rotate it to the
“hold during power loss” position ( Figure 66, p.
95 ).
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 S SE ET TU UP P, N NE EX XT T until
'Head Pressure Control Setup Submenu” is seen.
Press E
EN NT TE ER R.
10. Change the “Sump Drain Valve Relay Control” from
Drain to Hold.
Figure 64. Drain valve actuator with weather shield
Weather Shield
Shaft Set Screw
Drain Valve Actuator
U Un niitt S Stta arrttu up p