Trane CGAD020, Installation Operation & Maintenance

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CGAD-SVN02C-EN 15
Application
Considerations
Components of the Hydraulic Tubing of
the Evaporator
The figure below shows how to proceed to
install the water tubing. An air escape valve
is placed on the top part of the evaporator
and leaving water. Provide additional air
escape valves at the highest points of the
tubing in order eliminate it from the chilled
water system.
Drain of the Evaporator
The evaporator discharge connection
should be close to an available drain in
order to empty out the evaporator even
during the service. Install a slide valve on
the drain line.
Thermometers and Pressure Gauges
The installation of thermometers (items 5
and 12 of the figure) and pressure gauges
(item 9) is essential at the inlet and outlet
of chilled water. These instruments should
be installed close to the unit and have the
maximum scale of 1
o C for thermometers
and of 0.1 kg/cm 2 for pressure gauges.
Important: In order to avoid damaging the
evaporator, do not let the water pressure
exceed 150 psig.
We recommend installing a pressure
gauge with a connection at the water inlet
and outlet similar to item 9 in the figure in
order to avoid reading errors. The
installation of the pressure gauges and
thermometers should be at a height to
avoid parallax errors*. The thermometers
should also be of glass or mercury
scaling with colored fluid for contrast
purposes and to make reading them
easier.
- The pressure gauges should be
designed with siphons.
- Install slide valves in order to isolate the
pressure gauges when they are not being
used.
Use joints on the tubing in order to
facilitate the mounting and dismounting
services.
The inlet and outlet should have slide
valves in order to insolate the evaporator
during the execution of services and a
globe valve at the outlet to regulate the flow
of water.
Flow-Switch
Check the safety interlocking, especially
the flow-switch should be installed along
straight and horizontal sections with the
fins according to the diameter of the tubing
and the distance of the curves and valves
at least five times its diameter on each
side.
Water Treatment
The use of untreated or poorly treated
water could result in the formation of
scales, erosion, corrosion, algae, and
lime. We recommend that the services of a
water treatment specialist be contracted in
order to determine the treatment and if
needed, to carry it out. Trane do Brasil
does not take any responsibility for failures
with equipment due to using untreated or
poorly treated water.
* Parallax Error: Apparent dislocation of an object when the point of observation is changed. This especially refers to the apparent dislocation of the needle of a measuring instrument when looking at it
from a vertical direction (parallax error).
Fig. 07 - Components of the Hydraulic Tubing of the Evaporator