LCA
RG66000986 – Rev.00
13
ELECTRIC CONNECTIONS OF FLOW SWITCH OR DIFFERENTIAL WATER PRESSURE SWITCH
It is pre-wired in all LCA units. Frame 1, 2, 3 units feature a differential pressure switch that detects
pressure drops upstream and downstream from the evaporator (outgoing – returning water in the case
of units equipped with a pump system) ; Frame 4, 5 units have a blade-type flow switch installed in
series with water circuit.
ELECTRIC CONNECTIONS OF THE CIRCULATION PUMP
If selected on ordering, it/they is/are supplied pre-wired with all LCA units.
The pump must be started before the chiller and stopped after the latter (minimum
recommended delay: 60 seconds). If included as an option, this function is already
performed by the electric control board on the unit.
REMOTE CONTROLS
If you wish to include a remote control for switching the unit on and off, you must remove the bridge
between the contacts indicated in the wiring diagram and connect the remote ON/OFF control to the
terminals themselves [see annexed wiring diagram].
All remote controls work with a very low voltage (24 Vac) supplied by the insulating
transformer on the electric control board.
REMOTE SUMMER-WINTER SWITCHING
If you wish to include a remote control for switching the unit between the summer and winter operating
modes, you must remove the bridge between the contacts indicated in the wiring diagram and connect
the remote switching control to the terminals themselves [see annexed wiring diagram].
STARTING UP
PRELIMINARY CHECKS
-
Check that all the valves in the cooling circuit are open (liquid line).
-
Check that the electrical connections have been made properly and that all the terminals
are
securely tightened
. This check should also be included in a periodic six-month inspection.
-
Check that the voltage at the RST terminals is 400 V ± 5% and
make sure
the yellow indicator light
of the phase sequence relay is on. The phase sequence relay is positioned in the middle right part of
the electric control board; if the sequence is not duly observed, it will not enable the machine to
start.
-
Make sure there are no refrigerant leaks that may have been caused by accidental impacts during
transport and/or installation.
