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7.3 - Flow control
Evaporator flow switch and chilled water pump interlock
IMPORTANT: On 30XW-V/30XWHV units, the unit
water flow switch must be energised. Failure to follow this
instruction will void the Carrier guarantee.
The water flow switch is installed on the evaporator water
inlet and adjusted by the control, based on unit size and
application. If adjustment is necessary, it must be carried
out by qualified personnel trained by Carrier Service.
7.4 - Evaporator and condenser water box bolt
tightening
The evaporator (and condenser) are of the shell and tube
type with removable water boxes to facilitate cleaning.
Re-tightening or tightening must be done in accordance
with the illustration in the example below.
Water box tightening sequence
Legend
1 Sequence 1: 1 2 3 4
Sequence 2: 5 6 7 8
Sequence 3: 9 10 11 12
Sequence 4: 13 14 15 16
2 Tightening torque
Bolt size M16 - 171 - 210 Nm
NOTE: Before this operation we recommend draining the
circuit and disconnecting the pipes to be sure that the bolts
are correctly and uniformly tightened.
Legend
Master unit
Slave unit
Control boxes of the master and slave units
Water inlet
Water outlet
Water pumps for each unit (included as standard for units with hydronic
module)
Additional sensors for leaving water control, to be connected to channel 1
of the slave boards of each master and slave unit
CCN communication bus
Connection of two additional sensors
7.5 - Operation of two units in master/slave mode
The control of a master/slave assembly is in the entering
water and does not require any additional sensors (standard
configuration). It can also be located in the leaving water.
In this case two additional sensors must be added on the
common piping.
All parameters, required for the master/slave function must
be configured using the MST_SLV menu.
All remote controls of the master/slave assembly (start/
stop, set point, load shedding etc.) are controlled by the
unit con-figured as master and must only be applied to the
master unit.
Each unit controls its own water pump. If there is only one
common pump, in cases with variable flow, isolation valves
must be installed on each unit. They will be activated at the
opening and closing by the control of each unit (in this case
the valves are controlled using the dedicated water pump
outputs). See the Touch Pilot Control IOM for a more
detailed explanation.
30XW-V/30XWHV with configuration: leaving water
control
1
2
