■Proven Performance. CTI Certified. Plus SPX stands by
its responsibility for reliable thermal performance. We
designed it. We rate it. We guarantee it!
■Induced-Draft Design. Save on fan power. The fan will
operate in a warm atmosphere even in winter, so you’ll
never have to work on frozen mechanical equipment.
■Crossow Design. Save on pump power because you
only pay to move the water to the top of the tower. Gravity
does the rest. The mechanical equipment and water
distribution system are out where you can easily maintain
them.
■All-Season Reliability. Aquatowers perform as specified
in the heat of summer. They respond well to energy
management techniques in the spring and fall and
with appropriate fan controls, they can operate virtually
ice-free in the dead of winter. Plus they offer simple
maintenance all year long.
■Proven Corrosion Protection. Thousands of users
over more than 40 years confirm the value of heavy
galvanizing. And Marley’s Z-600 is the most effective
galvanizing used in the industry.
■ PVC Film Fill with Integral Drift Eliminators and
Louvers. If you’ve ever had to replace deteriorated
eliminators or louvers, you’ll appreciate this advantage.
Now those components are molded right in the PVC fill
sheets. Integral honeycomb louvers keep the circulating
water inside your tower—and off your roof!
■Select Your Aquatower on Our Website. The Marley
UPDATE web-based selection software—available at
www.spxcooling.com—provides Aquatower model
recommendations based on your specific design
requirements
■Simple, Flexible Installation. Just mount the motor, belts
and belt guard, install the outlet connection that suits
your needs—both side suction and bottom outlet are
provided, complete with screens—and adjust the float
valve. Attach air-inlet screens on models 494A and larger
and your Aquatower is ready for operation.
Page 3
3
/ The Marley Difference /
Today’s Aquatower may be the most space/energy-
efficient cooling tower available. Your needs have dictated
constant technological improvement. Thousands of
Aquatower users enjoy the benefits of eight major redesigns
and dozens of minor improvements in the past 40 years. For
example, PVC film-fill enables the Aquatower to reject more
heat per unit size. We also put the air inlet louvers and drift
eliminators right on the fill sheets. This new arrangement
saves you fanpower by improving airflow through the tower.
The Aquatower is a maintenance delight! You’ll
appreciate the way the Aquatower simplifies maintenance.
No hidden spray systems, tiny nozzles, or enclosed basins
here! You can easily replace and align V-belts from outside
the tower. You won’t have the chore and expense that goes
with high-power, blower fan towers.
All primary components of the Aquatower are open to
view. You can easily remove any debris from the upper basin
or nozzles while the tower is in operation.
Heavy mill galvanizing on all steel components prevents
base metal corrosion. You won’t have to worry about paint
chips clogging your strainers and nozzles, because there is
no paint to flake off. Heavy galvanizing also protects much
better than paint.
Above all, the Aquatower is readily available. You won’t
have to wait around—or accept second best—when you
need a cooling tower. We maintain an impressive stock of
completed towers at our own plants. A growing number of
local distributors can draw from that stock.
Contact your local distributor or Marley representative.
They’ll be glad to help you choose the proper model for
your needs. They can also help you with your layout and
piping.
You’ll enjoy single source responsibility and reliability
because we design and manufacture virtually all major
cooling tower components.
All Marley components are designed and selected to
be a part of an integrated system. For example, the spray
pattern from nozzles and the pressure drop through drift
eliminators both affect a fill’s heat transfer capacity. So, we
include that impact in our thermal analysis.
Drift eliminators must be effective at the air velocities
where fill is most efficient. So, we’ve carefully designed
both components to work together efficiently.
How many other cooling tower companies can offer
you this assurance? They may use Brand “A” nozzles with
Brand “B” fill and Brand “C” drift eliminators. When they all
come together, the whole may be less than the sum of the
parts.
Our total system approach assures that all the
parts work together to provide you the greatest total
performance.
And because we design specifically for cooling towers,
all our components will provide many years of service with
minimal maintenance.
Every Aquatower cooling tower carries a full one-year
warranty. The Aquatower you buy from us will work on
your job or we’ll make it right. Your warranty includes
thermal performance and every component of the tower.
The SPX Cooling Technologies warranty is your assurance
of performance—for a full year.
The Aquatower has inspired many imitators. Only
SPX Cooling Technologies can offer you the original.
Page 4
4
/ Schematic /
USE FOR
STATIC LIFT
L
INLET
C
L
TOWER
OUTLET
C
L
C
L
C
L
TOWER
W
D
S
E
C
B
H
MOTOR
INLET PIPING
(BY OTHERS)
A
SIDE OUTLET
BOTTOM OUTLET
TOWER COLLECTION
BASIN
VERTICAL
DISCHARGE
(OPTION-NOTE 3)
AIR INLET ELEVATION
Tower
Nominal Tons
Model
490A8902129216104 02175610
490B10902129216104021756101318.752"2" F
492A221206154322484322411219
492B281206154322484322411219203195 61.54"4" M
493A361816154922484322411524
493B421816154922484322411524203195 62.24"4" M
494A511816197227436082921829325123524031.56"6" MC
494B571816197227436082921829325123524032.26"6" MC
494C681816197227436082921929325123524033.76"6" MC
495A802426197527436082922134325123524033.76"6" MC
495B91242619752743608292213 4325123524035.56"6" MC
496A1113035198429535892922743334523526103.76"6" MC
496B1263035198429535892922743334523526105.56"6" MC
1. Nominal tons are based upon 35°C HW, 29.5°C CW, 25.5°C WB
and .68 m
note1
LWHABC note2DES
3
/hr per ton. The Marley UPDATE web-based selection
software provides Aquatower model recommendations based
on specific design requirements.
2. Minimum clearance for adequate air supply. Consult your Marley
sales representative or your local distributor if this clearance is
impractical for your job.
3. Vertical discharge hood is for applications in restrictive enclosures
or other locations where horizontal discharge is not desirable. CTI
Certification does not apply when this option is selected. Available
Dimensions
note3note6
note3
note3
4. Motors are 400 volt, 3-phase TEFC.
5. Motor, belt and belt guard ship uninstalled. Installation by others.
6. Outlet sizes shown are side outlets. All models except 490A and
490B have connections for both side and bottom outlet. Install the
desired connection and seal the unused opening with the coverplate provided. Pump suction should use side outlet. See page 9
for size and flow capacities of bottom outlets.
7. Overflow is a 2" F connecton located in side of collection basin.
8. Drain is a 2" F connection located in collection basin floor.
9. Makeup valve connection is 3/4" M located in tower side.
SIDE ELEVATION
Piping
Motor
kW
1318.252"2" F
203195 6.754"4" M
203195 61.54"4" M
Connection
Inlet
Outlet
note6
only on models 494A and larger.
Page 5
5
/ Support /
F
16mm DIAMETER HOLES
A
G
H
H
L
W
ANCHOR
BOLT
NORMAL
GAUGE
25mm
TOWER
COLLECTION BASIN
AIR INLET FACEAIR INLET FACE
25mm
25mm
ANCHOR
BOLT
C
L
C
L
F
L
ANCHOR
BOLT
25mm
25mm
ANCHOR
BOLT
C
L
C
L
ANCHOR
BOLT
ANCHOR
BOLT
C
L
C
L
G
H
H
W
ANCHOR
BOLT
ANCHOR
BOLT
C
L
C
L
SUPPORT
(BY OTHERS)
TOWER
COLLECTION
BASIN
16mm DIAMETER HOLES
TOWER
COLLECTION BASIN
B
NORMAL
GAUGE
MIN. BEARING WIDTH
AT EACH ANCHOR BOLT
51
SUPPORT
(BY OTHERS)
TOWER
COLLECTION
BASIN
SUPPORTING STEEL PLAN
OPTION ONE
Dimensions
Models with Vertical Discharge Hood Option
Tower
Model
490A-490B902101985191552
492A-492B120612601156106797
493A-493B181612061765106797
494A-49B181616801765152478
495A-495B2426168023751524787971294437338213
496A-496B3035168029 851524789512155539497290
LWFGH
494A-494C1816168017651524788161519380316234
495A-495B2426168023751524789681920480338234
496A-496B3035168029 8515247811782382596497290
1. Use this bulletin for preliminary layouts only. Obtain current drawings from your Marley sales representative or your local distributor.
2. Purchaser to provide tower supports complete with holes and bolts
for anchorage. All supports must be framed flush and level at top.
Maximum deflection to be 1/360th of span, not to exceed 13mm.
3. Maximum weight occurs with basin full to overflow level at shutdown.
Actual operating weight varies with flowrate and piping scheme.
4. Wind loads are based on 1.4 kPa and are additive to operating
loads. Reactions due to wind loads exceed those resulting from
seismic loads based on the 1997 UBC code, Zone 4 and an Importance Factor of 1.00 per Section 1634—Towers Not on a Building.
Shipping Weight
kg
198343
337633
445
634
Use this data for preliminary layouts only.
Obtain current drawing from your Marley sales
representative.
The Marley UPDATE web-based selection software
—available at spxcooling.com provides
Aquatower model recommendations based on
customer's specific design requirements.
SUPPORTING STEEL PLAN
OPTION TWO
VIEW BSECTION A
Max. Vertical
Reaction at
Anchor
Wind Load kg
Maximum
Operating
kg
905226238
1337334252161
Maximun
Operating Load
at Anchor
kg
8482
15816195
Max. Horizontal
Reaction at
Anchor
52
129
Page 6
6
/ Construction And Components /
■ Water Distribution System
Warm water flows through external piping (not included
with the tower) into a splash box chamber at the top of the
Aquatower. A splash box prevents the incoming water from
spilling out of the basin and helps provide uniform water
distribution. Water then flows by gravity from the basin
through nozzles to the fill.
■ Fill/Louvers/Drift Eliminators
Fill sheets include integral louvers and drift eliminators,
designed to minimize resistance to airflow. This patented
arrangement prevents water from escaping the fill sheets,
assuring proper heat transfer throughout wide variations in
airflow. Users find this fill operates ice-free even in extremely
cold weather.
The thermoformed .4mm thick PVC fill sheets withstand
hot water temperatures as high as 52°C. Fill sheets are
immune to biological and corrosive decay and their flame
spread rating is less than 25 per ASTM E-84. Galvanized
structural tubes support and stabilize the fill. They also hold
the bottom of the fill sheets above the cold water basin
floor to simplify basin cleaning. Removable 25 x 25 mesh
galvanized air inlet screens keep larger airborne trash out of
the collection basin and fill area.
Eliminator air-seal removed showing distribution area above fill
Hot water distribution basin covers are provided as
standard equipment to keep the distribution basin free from
airborne debris and to reduce the likelihood of biological
growth.
All Aquatowers use Marley “Spiral Target” nozzles.
These inert polypropylene nozzles are evenly spaced
thoughout the distribution basin to assure uniform water
distribution over all portions of the fill. Their large openings
resist clogging. Nozzles are easy to remove and replace if
you ever want to change the design water flow rate.
Spiral-target distribution nozzle
MX Fill
■ Cold Water Collection Basin
The Aquatower’s collection basin reduces operating
weight, simplifies basin cleaning, and assures proper
outflow. Water flows from the elevated area under the fill
into the basin’s rear depressed section, where side suction
piping connects. A bottom outlet is also available for gravity
flow applications.
Standard equipment on each tower basin includes:
a screened suction connection; a threaded overflow
connection; a threaded and plugged drain connection;
and a float-operated make-up valve. Models 492A through
496B also include a bottom outlet conforming to flat flange
specification. A blank cover plate is provided to seal the
outlet connection not used.
Page 7
7
/ Construction And Components /
■ Mechanical Equipment
Belt-driven propeller fans insure design airflow at
minimum power. Fans are supported by an oil-lubricated
tapered roller bearing assembly with remote oil reservoir.
For ease of maintenance all drive components are
accessible from outside the tower.
Fan drive motor showing adjustable base and belt guard
■ Hoisting and Handling
Hoisting instructions on each tower explains how to use
a spreader-bar and slings beneath the cold water basin floor
to hoist the Aquatower. The tower’s design also allows easy
handling with a forklift.
Fan and fan guard. Guard is easily removed for access to
fan and drive belts
Fan drive motors are TEFC designed specifically for
cooling tower use. Kilowatts and electrical characteristics
appear in the table on page 4. Other types of motors are
available.
Caution
The cooling tower must be located at such distance and
direction to avoid the possibility of contaminated tower
discharge air being drawn into building fresh air intake
ducts. The purchaser should obtain the services of a
Licensed Professional Engineer or Registered Architect
to certify that the location of the tower is in compliance
with applicable air pollution, re, and clean air codes.
■ Safety
Standard Aquatower safety features include fan guards
and belt guards. Fan guards consist of welded heavy gauge
steel wire hoops and spokes, hot dip galvanized after
fabrication. The galvanized steel belt guard encloses both
belts and pulleys. Guards are easily removed for servicing.
■ Construction and Finish
Aquatowers offer the corrosion protection of Z-600
galvanized providing long term protection for the steel.
Assembly hardware is also galvanized.
Page 8
8
/ Freeze Prevention /
When the ambient air temperature falls below 0°C, the
water in a cooling tower can freeze. Marley Technical Report
#H-003“Operating Cooling Towers in Freezing Weather”
describes how to prevent freezing during operation. Ask your
Marley sales representative for a copy or download from our
website.
Water collects in the cold water basin during shutdowns,
and may freeze solid. You can prevent freezing by adding
heat to the water left in the tower. Or, you can drain the tower
and all exposed piping at shutdown.
■Electric Basin Heaters
Provide an electric immersion heater for each cell of the
tower to prevent freezing of water in the collection basin
during periods of shutdown. The rod type heater is installed
in the side of the cold water basin.
Each heater will include an integral thermostat, set
point nominally 4°C but adjustable to suit local operating
requirements.
Any exposed piping that is still filled with water at
shutdown —including the makeup water line—should be
electrically traced and insulated (by others).
■Indoor Tank Method
In this type of system, water flows from an indoor tank,
through the load system, and back to the tower, where it is
cooled. The cooled water flows by gravity from the tower to
the tank located in a heated space. At shutdown, all exposed
water drains into the tank, where it is safe from freezing.
The table on page 9 lists typical drain-down capacities
for all Aquatower models. Although we do not produce
tanks, many of our representatives offer tanks supplied by
reputable manufacturers.
The amount of water needed to successfully operate
the system depends on the tower size, flow and the volume
of water contained in the piping system to and from the
tower. You must select a tank large enough to contain those
combined volumes—plus a level sufficient to maintain
a flooded suction on your pump. Control makeup water
according to the level where the tank stabilizes during
operation.
You should always use a bottom outlet for this type of
piping system. The following table lists the flow capacities for
bottom outlets.
Basin Heater Selection
Tower
Model
490A2 kW3 kW2 kW3 kW
490B2 kW3 kW2 kW3 kW
492A2 kW3 kW2 kW3 kW
492B2 kW3 kW2 kW3 kW
493A2 kW3 kW3 kW3 kW
493B2 kW3 kW3 kW3 kW
494A2 kW3 kW4 kW3 kW
494B2 kW3 kW4 kW3 kW
494C2 kW3 kW4 kW3 kW
495A3 kW3 kW6 kW4.5 kW
495B3 kW3 kW6 kW4.5 kW
496A3 kW4.5 kW6 kW6 kW
496B3 kW4.5 kW6 kW6 kW
-12°C Ambient-25°C Ambient
Tank Heater
Component
Heater
Tank Heater
Component
Heater
1. Required kw is the amount of heat needed to maintain +4.5°C basin
water temperature at the indicated ambient air temperature.
2. Tank heaters shown are 220 volts, single-phase.
3. Com p one nt hea ter s s how n a re 400 vo lts , t hre e-p has e.
Options or special heater selections may add several weeks to
delivery.
4. Heaters do not operate continuously. Heaters cycle on and off
automatically as basin water temperature dictates.
5. Contact your Marley sales representative for selections appropriate
for other ambient conditions than those shown here.
Page 9
9
/ Field Assembly /
Drain-Down Capacity
Tower Model
490A
490B
492A
492B
493A
493B
494A
494B
494C
495A
495B
496A
496B
Range of Tower Design m3/hr
3.4 - 5.9106
6.2 - 11.6114
11.8 - 19.3125
19.5 - 34.7136
4.77 - 12185
12.6 - 209204
21 - 34.3227
34.5 - 47.9246
7.5 - 18.8291
19 - 32.7318
32.9 - 54356
54.2 - 74.5382
13.6 - 32507
32.3 - 51.5549
51.7 - 85.4613
85.6 - 127.8674
18.6 - 43.6689
43.8 - 61.3727
61.5 - 116.5829
116.7 - 173.3912
23.6 - 44.5863
44.7 - 64.9920
65.1 - 112.81026
113.1 - 218.71211
Maximum Drain-Down
litres
Volumes shown are maximums for the flowrate ranges indicated.
Actual volumes will usually be less. Contact your local Marley sales
representative for more specific information.
Bottom Outlet Maximum m3/hr
Tower
Model
492A - 492B275151na
493A - 493B276179na
494a - 494B - 49 4C327079142
495A - 495B327079193
496A - 496B327079193
4"6"8"10"
Outlet Diameter
1. Maximum m3/hr applies to both pump and gravity flow piping systems. The outlet piping on gravity flow systems must have sufficient
vertical drop to overcome all other head losses in the system.
2. Bottom outlet is not available on Models 490A and 490B.
Note: For economical transportation, Aquatowers are normally
packaged unassembled when shipped from the UK by sea or air
freight.
■Field Assembly
If you choose to assemble your Aquatower at the job site,
your Aquatower will be shipped unassembled with complete
assembly instructions.
The following table shows the sizes and weights of the
largest Aquatower components for each model. You can
use this information to plan your rigging and transportation
needs.
Unassembled tower shipment may add 3 to 5 weeks to
normal lead times. Your Marley sales representative will be
glad to help you plan for your unique needs.
Component Sizes and Weights
Tower Model
490A
490B
492A
492B
493A
493B
494A
494B
494C
495A
495B
496A
496B
ComponentSize mmWeight kg
Collection Basin End305 x 330 x 9147
Collection Basin Floor76 x 762 x 81311
Front Panel51 x 914 x 11210
Casing Panel51 x 102 x 13220
Distribution Basin203 x 406 x 8138
Collection Basin End356 x 406 x 12211
Collection Basin Floor76 x 914 x 11217
Front Panel51 x 122 x 17324
Casing Panel51 x 66 0 x 160016
Distribution Basin203 x 406 x 11211
Collection Basin End356 x 406 x 18317
Collection Basin Floor76 x 914 x 172726
Front Panel51 x 940 x 18316
Casing51 x 660 x 160016
Distribution203 x 406 x 17317
Collection Basin End457 x 457 x 182922
Collection Basin Floor102 x 864 x 172726
Front Panel51 x 1117 x 182919
Casing Panel51 x 1016 x 193029
Distribution Basin203 x 711 x 172724
Optional Discharge Side51 x 1041 x 195617
Optional Discharge Floor229 x 1143 x 172721
Collection Basin End457 x 457 x 243829
Collection Basin Floor102 x 864 x 233834
Front Panel51 x 1118 x 243826
Casing51 x 1016 x 193029
Distribution Basin203 x 711 x 233732
Optional Discharge Side51 x 1041 x 195617
Optional Discharge Floor229 x 1143 x 160019
Collection Basin End457 x 457 x 304836
Collection Basin Floor102 x 864 x 294643
Front Panel51 x 1168 x 304833
Casing Panel51 x 1016 x 213432
Distribution Basin203 x 711 x 29 4640
Optional Discharge Side51 x 1143 x 195617
Optional Discharge Floor229 x 1143 x 195625
Page 10
10
/ Options /
OptionDescriptionOptionDescription
Field Assembly
Where unique space restrictions or
rigging conditions demand, Aquatowers
can be shipped ready for field assembly
by others. Complete step-by-step
assembly instructions are provided.
Stainless Steel
Construction
Control System
All Aquatower models are available
with stainless steel structure. Or you
can choose a galvanized tower with
a stainless steel cold water collection
basin. Your Marley sales representative
can help you choose the amount of
corrosion resistance necessary for your
installation.
Factory-installed control center in
IP55,IEC enclosure mounted on tower
casing. Complete with thermostat controller for single or two-speed motors to
maintain chosen cold water temperature.
Vertical
Discharge
Hood
This option is available on Models 494A
and larger. It provides vertical discharge
of the air leaving the tower. Hoods are
galvanized steel. They ship separately
for installation by others. A large access door provides entry to the fan and
mechanical equipment.
For use in restrictive enclosures or other
site situations where horizontal discharge
is not desirable. CTI Certification does
not apply when this option is selected.
Page 11
11
/ Specifications /
Base: Furnish and install an induced-draft, crossflow, factory-
assembled, steel cooling tower of ____ cell(s), as shown
on plans. Tower shall be similar and equal in all respects
to Marley Series 4900 Aquatower, Model _______. Tower
must be warranted by the manufacturer for one year from
date of shipment.
3
Performance: Tower shall cool ____ m
/hr of water from ____ °C
to ____ °C at a design entering air wet-bulb temperature
of ____ °C and its thermal rating shall be certified by the
Cooling Technology Institute.
Construction: Structural components of the tower, including
the cold water basin, framework, mechanical equipment
supports, casing, hot water basin, and fan cylinder shall
be fabricated of heavy-gauge steel, protected against
corrosion by Z-600 galvanizing per BS EN 10327:2004.
All components subjected to factory welding shall be hot
dip galvanized after fabrication per BS EN 150 1461:1999.
Cold galvanizing is not acceptable.
Motor: Motor(s) shall be ____ kW, Totally Enclosed, specially
insulated for cooling tower duty. Speed and electrical
characteristics shall be 1500 (or 1500/750) RPM, single-
winding, ____ phase, ____ hertz, ____ volts. The motor
must be located out of the saturated discharge air
stream.
Mechanical Equipment: Fan(s) shall be adjustable-pitch
propeller type. Fan shall be driven through V-belt(s) with a
minimum service factor of 1.5 based on full motor kW and
protected with a belt guard. The fan and fan pulley shall
be supported by oil lubricated tapered roller bearings in
a cast iron housing with externally accessible remote oil
reservoir for easy maintenance.
Fill, Louvers and Drift Eliminator: Fill shall be film-type,
thermoformed PVC, with louvers and drift eliminator
formed as part of each fill sheet. Fill shall be suspended
from hot dip galvanized structural tubing supported from
the upper tower structure, and shall be elevated above
the floor of the cold water basin to facilitate cleaning. Air
inlet faces of the tower shall be free of water splash-out.
Guaranteed drift losses shall not exceed 0.005% of the
design flow rate.
Hot Water Distribution System: An open basin above the fill
bank shall receive hot water piped to each cell of the
tower. The basins shall be equipped with removable
covers to keep out debris. This basin shall be installed and
sealed at the factory. Water shall enter the basin through
a removable wave-suppressor splash box. The basin
shall be no less than 162mm deep to provide adequate
freeboard against overflow and splash-out. Removable
and replaceable polypropylene nozzles installed in the
floor of the basin shall provide full coverage of the fill by
gravity flow. Nozzles must all have the same orifice size
and be spaced symmetrically in both longitudinal and
transverse directions.
Cold Water Basin and Accessories: The cold water basin shall
be factory sealed. For maximum installation flexibility,
basin accessories shall include both a side suction
connection and a hole and bolt circle in the basin floor
suitable for gravity flow. Both connections shall include
a debris screen and anti-cavitation device. A factory-