Maintenance, Belt tensioning – SPX Cooling Technologies Cooling Tower Marley MD User Manual
Page 21
21
table shows the minimum amount of blowdown (percent of flow) required
to maintain different concentrations with various cooling ranges*:
* Range = Difference between hot water temperature coming to tower and cold water
temperature leaving tower.
EXAMPLE: 700 GPM circulating rate, 18°F cooling range. To maintain
4 concentrations, the required blowdown is 0.458% or .00458 times 700
GPM, which is 3.2 GPM.
If tower is operated at 4 concentrations, circulating water will contain four
times as much dissolved solid as the makeup water, assuming none of the
solids form scale or are otherwise removed from the system.
When water treatment chemicals are added, they should not be in-
troduced into the circulating water system via the cold water basin
of the cooling tower. Water velocities are lowest at that point, which
results in inadequate mixing.
Belt Tensioning
Always shut off electrical power to the tower fan motor prior to
performing any inspections that may involve physical contact with
the mechanical or electrical equipment in or on the tower. Lock out
and tag out any electrical switches to prevent others from turning
the power back on. Service personnel must wear proper personal
protective clothing and equipment.
On the MD5008 and MD5010, the fan motor and belt adjustment mecha-
nism is located outside the tower. Remove the motor protection hood by
loosening the two thumbscrews on top and hinge the hood up and out of
the way. Also, remove the motor sheave safety bracket and set aside. See
the following images.
Maintenance
Warning
Note
e
g
n
a
R
g
n
il
o
o
C
s
n
o
it
a
rt
n
e
c
n
o
C
f
o
r
e
b
m
u
N
X
5
.
1
X
0
.
2
X
5
.
2
X
0
.
3
X
0
.
4
X
0
.
5
X
0
.
6
)
C
°
8
7
.
2
(
F
°
5
8
7
.
8
3
.
5
2
.
8
1
.
1
1
.
8
0
.
6
0
.
)
C
°
6
5
.
5
(
F
°
0
1
8
5
.
1
8
7
.
1
5
.
8
3
.
5
2
.
8
1
.
4
1
.
)
C
°
3
3
.
8
(
F
°
5
1
8
3
.
2
8
1
.
1
8
7
.
8
5
.
8
3
.
8
2
.
2
2
.
)
C
°
1
1
.
1
1
(
F
°
0
2
8
1
.
3
8
5
.
1
5
0
.
1
8
7
.
1
5
.
8
3
.
0
3
.
)
C
°
9
8
.
3
1
(
F
°
5
2
8
9
.
3
8
9
.
1
2
3
.
1
8
9
.
4
6
.
8
4
.
8
3
.
.
e
t
a
r
r
e
t
a
w
g
n
it
a
l
u
c
ri
c
e
h
t
f
o
%
2
0
.
0
f
o
tf
ir
d
n
o
d
e
s
a
b
e
r
a
s
r
e
il
p
it
l
u
M