Installation and Maintenance Manual

Installation - Mechanical
SCXG-SVX01H-EN 33
Waterside Piping Arrangements
Install a condenser water pump between the cooling tower
(either open or closed) and the self-contained unit. Lay out
the remainder of the system’s condenser piping in reverse
returns.This helps balance the system by equalizing the
length of supply and return pipes. Multistory buildings
may use a direct return system with balancing valves at
each floor.
Install the supply riser and its return in close proximity.
Furnish both with permanent thermometers to check the
waterside balance during start-up and routine
maintenance checks.
Also, include strainers at each pump inlet and unit. Install
drain valves at the riser’s base to allow drainage points for
system flushing during start-up and routine maintenance.
For condenser draining and header removal, include a
shutoff/balancing valve on the entering and leaving
waterside pipes, drain tees, and unions of each unit.
Note: Unit does not have floor drains.
Water Temperature Requirements
Do not allow the entering water temperature to go below
54°F (12.2°C) on units with constant water flow (basic
piping).This will cause the compressors to shut down and
the mechanical cooling function will lockout. However, the
economizer (if enabled) will continue to function.The
compressors will reset when the entering water
temperature reaches 58°F (15°C).
Units with variable water flow (intermediate piping) have
a modulating condensing pressure control valve that
allows compressor operation down to entering water
temperatures of 35°F (2°C).
For more information on constant and variable water flow,
see the Sequence of Operation section of this manual.
Note: Units with a waterside economizer can be set from
the human interface panel for variable or constant
water flow.
Figure 31. Direct condenser connections
Figure 32. Condenser water piping components for cooling tower system