20
Water Piping
Piping connection
CAUTION - Evaporator Damage!
The water connections to the evaporator are to be flange type. Do not attempt to weld these
connections, because the heat generated from welding can cause microscopic and macroscopic
fractures on the cast iron water boxes that can lead to premature failure of the water box.
CAUTION - Water Strainer!
To prevent evaporator damage, pipe strainers must be installed in the water supplies to protect
components from water born debris. Trane is not responsible for equipment - only - damage caused
by water born debris.
CAUTION - Equipment Damage!
Thoroughly flush all the water piping before making the final piping connections to the unit after
external water piping installation and leakage test. Construct a temporary bypass around the unit for
flushing to prevent damage to internal components of the evaporator.
Proper system design and installation procedures should be followed closely. The system must be
constructed with pressure tight components and thoroughly tested for installation leaks. Typical chilled water
piping system, as
1.
Install field-supplied pressure gauges in the water inlet and outlet of the evaporator.
Note: for assembly unit, install pressure gauges in the water inlet and outlet of each unit.
2.
Use vibration eliminators to prevent vibration transmission through the water lines.
3.
If desired, install thermometers in the lines to monitor entering and leaving water temperatures.
4.
A field-supplied water strainer with a minimum size of 20 mesh must be installed close to the evaporator inlet
to prevent debris from damaging internal tubes of the evaporator.
5.
Install a balancing valve in the leaving water line to control water flow balance. Install shutoff valves on both
the entering and leaving water lines so that the evaporator can be isolated for service.
6.
Install flow switch in the water outlet of the evaporator with pump interlock to prove system water flow.
CAUTION - Dual water flow switch!
For assembly unit RTXC 310/330/360/400/440XE, install appropriate water flow switches at the outlet of
evaporator for both master and slave units.
7.
A vent is provided on the top of the evaporator waterbox. The evaporator can be drained by removing the
drain plugs from the bottom of the waterbox. Field- supplied drainage pipe installed should apply to all local
and national codes.
8.
Be sure to provide additional vents at high points in the piping to bleed air from the water system.
9.
Insulate all water pipings after leakage test and flushing and provide proper support for the piping.
CAUTION - Equipment Damage!
To prevent damage to chilled water components, do not allow evaporator pressure to exceed water
side maximum working pressure indicated on the evaporator nameplate.
10.
The external water piping should be cleaned before the unit is connected to prevent damage to internal
components of the evaporator. construct a temporary bypass around the unit during piping clean to prevent
damage to internal components of the evaporator.
