Maintenance; Cleaning The Evaporator (Rtwa And Rtua); Cleaning The Condenser - Trane R Series Installation Operation & Maintenance

RLC-SVX07A-EN

Maintenance

This section describes specific maintenance procedures which must be
performed as a part of the normal maintenance program for this unit. Be
certain that electrical power to the unit is disconnected before performing
these procedures.
WARNING
Prevent Injury!
Position all electrical disconnects in the "OPEN" position and lock
them, to prevent injury or death due to electrical shock.

Cleaning the Evaporator (RTWA and RTUA)

The evaporator water system is a part of a closed loop and should not
accumulate an appreciable amount of scale or sludge. If it is determined that
the chiller is fouled, first attempt to dislodge any foreign material by
backflushing the system several times. If this does not work satisfactorily,
chemically clean the chiller using the procedures outlined in Paragraph
"Mechanical Cleaning (RTWA)" on Page

Cleaning the Condenser

General (RTWA)
Water available for condensing frequently contains minerals or other contam-
inants that collect on the inside of the condenser tubes as carbonate scale.
Scale accumulation will accelerate with high condensing temperatures and
use of water with high mineral content. Cooling towers collect dust and
foreign material which also deposit on the condenser tubes, forming sludge.
To maintain maximum efficiency, the condenser must remain as free of these
deposits as possible. Even a very thin layer on the inside tube surfaces
reduces the heat transfer ability of the condenser. Indications of scale
deposits are decreased water flow through the condenser, reduced temper-
ature differential between entering and leaving condenser water and abnor-
mally high condensing temperatures.
There are two accepted methods of cleaning condenser tubes, as discussed
in the following paragraphs.
Mechanical Cleaning (RTWA)
The mechanical cleaning method is used primarily to remove sludge and
other loose material from the condenser tubes. Follow the steps below:
1. Turn off the chiller and condenser water supply.
2. Break piping connections at the unions.
3. Remove the condenser waterboxes.
4. Run a round nylon brush from end to end through the tubes, to loosen
deposits.
5. Flush the tubes with water. Then inspect the tubes for scale accumula-
tion. If there is no scale in the tubes, reassemble the condenser and pip-
ing.
6. If there is scale in the tubes, follow the procedures in Paragraph
cal Cleaning (RTWA)" on Page
137.
138.
"Chemi-
137