2.4.6
Avoid the use of sharp bends and elbows that
will restrict water flow. Loops and bends in the
lines may create air pockets, which substan-
tially reduce the flow of coolant and can
contribute to overheating.
2.4.7
Coolant and coolant supply lines should be
free of foreign material (a 500 micron water
filter is recommended). In the event that
contaminated water is used as a coolant
(not generally recommended), use of a
multi-stage filter / strainer may be desirable
to avoid the need for frequent cleaning of
fine mesh filters.
2.4.8
Figure 5 illustrates a typical closed loop liquid
to liquid coolant system. The heat
exchanger and temperature control
would be replaced with a radiator, fan
and motor in a liquid to air system.
2.4.9
The coolant supply temperature at the inlet
should be 100
o
F (38
o
C) or lower. The coolant
outlet temperature should not exceed the
values given in Table 8. However,
in no
event
should there be more than a 50
o
F
(28
o
C) temperature rise between inlet and
outlet. See Table 8 for maximum allowable
outlet coolant temperature with various
water/ethylene glycol mixtures and other
cooling media.
2.4.10
Open Loop Systems
For efficient operation of the WCB2, an
adequate supply of filtered fresh water is
required. (See 2.4.1 - 2.4.2). Excessive water
hardness promotes the formation of scale
deposits, which, in time, will affect the service
life of the WCB2 unit. Water of high acidity or
high in corrosive salts may cause electrolytic
corrosion between the dissimilar metals used in
the water cavities. Water treatment should be
considered if the properties of the water exceed
the following:
Equivalent calcium carbonate content
hardness): Maximum 100 p.p.m.
pH value: 7.0 to 9.0.
Open loop systems should be thor-
oughly flushed with clean fresh water
after operation to reduce the corrosive
effects of contaminants on internal
components.
2.4.11
Closed Loop Systems
For efficient operation of the WCB2 in a
closed loop system, ethylene glycol coolant
conforming to SAE Standard J1034 should be
used. For preparation of the proper concentra-
tion of a water/ethylene glycol mixture, use
make-up water which is low in corrosive ions
such as chlorides and sulfates.
Recommended pH value of the water/ethylene
glycol mixture: 7.5. to 10.5.
Figure 5
WCB 11070 VP 4.2 Format
11
© Copyright Eaton Corp., 2003. All rights reserved
April 2002 (Revised June 2003)
