Carrier 5H - Manual (Page 30)

CONDENSERS
Limitations - On most installations the condenser
is selected within the recommended conditions
that are specified in the ARI Standards. The two
main considerations are:
1. The water velocity is within a range of 3 to
10 feet per second. (The purpose of this is to
minimize corrosion and erosion.)
2. It is considered good practice to select the
condensers on the basis of a leaving terminal
difference between 6 F and 12 F. In general,
terminal differences higher than these are used
only
where the condensing water temperature
is quite low or where special conditions make
it economical to do so. A high terminal dif­
ference not only makes the effect of fouling
more pronounced but since the condenser vol­
ume is likely to be small tbe effect on non­
condensable gases will be greater.
Table 23 lists maximum water velocities as
stated in the Carrier System Design Manual.
These limits are above the ARI recommended
values but are generally accepted by industry on
jobs where ARI conformance is not specified. See
Part 5 of the Carrier System Design Manual for
further details.
Table 24 lists the condenser water quantities
for various water velocities. Higher velocities
may be calculated by use of the formulas given
under Table 24.
Table 23 - Max Condenser Tube Water Velocity
OPERATING HOURS
PER YEAR
MAXIMUM TUBE
WATER VELOCITY
(fps)
Up to 1500 12
2000 11 5
3000 11
4000 10
6000 9
8000 8
The table below gives a convenient means of
obtaining tube water velocities at various gpm
values.
Table 24 - Condenser Gpm at Various Water Velocitiest
MINIMUM PASS* MAXIMUM PASSt
Water Velocity - Fps
CONDENSER 3 5 7 9 10 3 5 7 9 10
5F20 6 11 15 20 22 3 5 8 10 11
5F30 8 15 22 29 32 4 7 11 14 16
5F40 16 27 39 50 56 8 14 19 25 28
5F60 20 35 50 65 72 10 17 25 32 36
09RH027 42 70 98 126 140 21 35 49 63 70
09RH043 63 105 147 189 210 31 5 52 5 73.5 94 5 105
09RH054 63 105 147 189 210 31,5 52.5 73.5 94 5 105
09RH070 79 131 183 236 262 39 5 65 5 91 5 118 131
09RH084 93 155 216 279 310 46 5 77.5 108 139.5 155
09RH097 93 155 216 279 310 46.5 77 5 108 139 5 155
09RH127 148 247 346 445 494 74 0 123.5 173 222 5 247
*Double circuit for 5F20 and 30.
tSingle circuit for 5F20 and 30
tWithin ARI Standard Recommendations
Water velocity formulas: (Use for velocities above 10 fps.)
V
5F20
Condenser:
5F40 thru
09RH127:
V
gpm X 0.92
~ no. of circuits
gpm X passes x 1.4
total tubes
5F30
Condenser:
V =
gpm
X
0.65
no. of circuits
SECTION
PAGE
DATE
5F,H-1XA
30
10-66 Printed in U.S.A.
S U P E R S E D E S
SECTION
5F,H-1X
PAGES 1-42
DATE 11-63