Chemically Cleaning The Evaporator - Trane RTRA Series Installation Operation & Maintenance

Chemically cleaning the evaporator

The chilled water system is a closed-loop and therefore
should not accumulate scale or sludge. If the chiller
becomes fouled, first attempt to dislodge the material by
backflushing the system. If, after several attemps, chemi-
cally clean the evaporator.
Caution : Do not use an acid type cleaning agent that will
damage steel, galvanized steel, polypropylene, or inter-
nal copper components.
With this information, water treatment firms will be able to
recommend a suitable chemical for use in this system.
A typical configuration for chemical cleaning is shown in
figure 17. The supplier of the cleaning chemicals must pro-
vide or approve :
All of the materials used in this configuration
The amount of chemicals used
Figure 17 - Chemical cleaning configuration
Shutoff valves
Circulating
pump
The length of time the chemicals are used
Any safety precautions and handling instructions
Service pumpdown
The UCM-CLD provides a one-time "Service Pumpdown"
mode with which the service engineer can start a particu-
liar compressor and run it for one minute to pump-down
the refrigerant circuit low side.
Caution : Do not use this procedure more than once. The
suction pressure must be monitored with an external gauge.
If the suction pressure drops below 1,3 bar, press the "Stop"
key to cycle off the compressor.
To evaporator water inlet
From evaporator water outlet
Cleaning solution
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