Unit installation

34
COOLER PIPING CONNECTIONS
After the unit has been leveled, the external water piping may be made up. The following piping guidelines are served
to ensure satisfactory operation of the units. Failure to follow these recommendations may cause damage to the unit
or loss of performance and may nullify the warranty.
• Water piping must be connected correctly to the unit i.e., water must enter from the inlet connection on the cooler
and leave from the outlet connection.
• A flow switch must be installed in the field piping at the outlet of the cooler (in horizontal piping) and wired back to
the unit control panel using shielded cable. There should be a straight run of piping of at least five pipe diameters
on either side of the flow switch. Paddle type flow switches can be obtained from ZAMIL which are supplied as
optional items.
A flow switch is required to prevent damage to the cooler caused by the unit
operating without adequate liquid flow. The flow switch should be connected in
the external interlock as shown in the wiring diagram in the control panel. The
flow switch MUST NOT be used to start and stop the unit.
• The chilled water pump(s) installed in the piping system should discharge directly into the unit cooler. The pump(s)
may be controlled external to the unit - but an interlock must be wired to the unit control panel (as shown in the
wiring diagram) so that the unit can start only upon proof of pump operation.
• Flexible connections suitably selected for the fluid and pressure involved should be provided as mandatory in order
to minimize transmission of vibrations to the piping / building as some movement of the unit can be expected during
normal operation. The piping and fittings must be separately supported to prevent any loading on the cooler.
The cooler must be protected by a strainer, preferably of 20 mesh, fitted as
close as possible to the liquid inlet connection, and provided with a means of
local isolation.
CAUTION
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CAUTION
!