Crossflow Cooling Tower
Unlock Top Performance with 5 New Keys
The NC offers the highest tonnage per cell and the highest ASHRAE 90.1 performance available – up to 2189 tons (9614 kW).
Independently Validated Sound Data.
Marley towers are the only package cooling towers tested per CTI ATC-128 test code by third-party CTI-licensed test agents and certified acoustical engineers. NC sound levels are independently verified to meet published sound levels.
Lowest Drift Rates.
Lower drift means less water escapes the tower, providing cleaner surroundings. The new patent-pending MarKey™ Eliminator achieves the lowest available drift in a crossflow cooling tower.
More Vibration Protection.
New generation mechanical and solid-state vibration switches ensure smoother start up, safe operation and long service life.
Cold Water Basin Inlet Covers.
New optional SunShield™ Inlet Covers protect the cold water basin from sunlight and debris which can contribute to algae growth.
The Marley NC Cooling Tower has set the standard for high efficiency and low maintenance since its introduction in 1968. Our nearly 100 years of cooling tower engineering know-how is utilized so that the NC Cooling Tower you select today provides the broadest range of configurations and the highest cooling capacities available in a package cooling tower.
Available fully factory assembled or for field-erected installation, the Marley NC Cooling Tower incorporates Marley-engineered components specifically designed for cooling tower service with time-tested tower design – a combination that has proven effective in thousands of cooling installations around the globe.
*As compared to other leading manufacturers.
ASHRAE 90.1 compliant
Thermal Capacity: 101 – 2189 tons (444 – 9623 kW) per cell
Quiet By Design: All Marley NC Cooling Towers are designed for low sound levels using high efficiency low sound fans and heat transfer media with low splash noise characteristics. Sound data is developed and tested per CTI ATC-128 guidelines to ensure accuracy and data reliability.
- The Quiet Fan option provides sound levels that meet intermediate sound level requirements. Models are configured using premium efficiency motors, quiet gear drive reduction with matched gear sets and high solidity premium efficiency fans.
- The Ultra Quiet Fan option and Sound Attenuation components are designed for the most extreme sound level requirements.
Long Life Construction: Rugged G235 heavy mill galvanized steel is standard; Series 300 stainless steel is an optional upgrade to the tower structure and includes a 5-year limited warranty. Marley Cooling Towers are manufactured in ISO-certified facilities, attesting to our commitment to comprehensive quality processes and systems.
Performance for All Seasons: The Marley NC Cooling Tower is designed to operate year round as specified and will adapt to various energy-management approaches.
Low Maintenance/Less Downtime: The Marley NC Cooling Tower can be maintained while operating, which translates to less downtime for mission-critical facilities.
- The water distribution system may be inspected and cleaned without turning off the pumps.
- The standard gear drive system is designed to operate a full five years without oil change or efficiency loss; comparable belt-drive systems require more frequent adjustment and replacement.
Removable fan guard of welded, heavy gauge rods is hot dip galvanized after fabrication.
Eased inlet fan cylinder ensures full area, low-turbulence airflow through the cylinder.
High efficiency fan has wide chord design for maximum efficiency at low fan tip speeds.
Marley System 5 Geareducer® drive
- Requires no oil changes for five full years, providing significant maintenance costs savings.
- Marley SofTork™ MC coupling, designed specifically for Variable Frequency Drive (VFD) applications absorbs excessive shock loads at start-up.
- Marley Power Belt™ drive, for models up to 60 hp, offers 40,000-hour bearing life and easy belt replacement.
TEFC fan motor has 1.15 service factor and variable torque and is specially insulated for humid cooling tower duty and extended life.
NC air movement package, including the structural support, is guaranteed against failure for five full years. The motor is separately warranted by the motor manufacturer.
WATER DISTRIBUTION SYSTEM
Multiple piping options – the right connections for your application – include single inlet, dual inlet, top, side or bottom inlet, side outlet or bottom outlet.
Gravity flow distribution system
- Allows easy, nonrestrictive, on-line maintenance.
- Basin covers are standard and can serve as a walking surface with guardrail option.
Marley Spiral Target polypropylene nozzles deliver precise distribution of water over the fill area.
Marley MX thermoformed PVC film fill
- Is suspended from structural steel tubing.
- Integral louvers and eliminators keep circulating water confined to fill, even at low air rates.
Drift Eliminators provide drift rates as low as 0.0005% of the design flow rate.
Crossflow configuration provides easier and safer on-line maintenance.
Steel construction – G235 (Z725) heavy mill galvanized steel is standard; Series 300 stainless steel is optional.
Factory assembly ensures final field installation will be uncomplicated. The cooling tower can also ship in pieces for assembly on site.
Two large access doors provide non-confining, quick visual inspection of cold water basin, internal structure, drift eliminators and mechanical equipment in the plenum area.
High efficiency axial fan, with adjustable-pitch blades, permits maximum utilization of rated horsepower and allows field adjustments to optimize performance.
Marley System 5 Geareducer drive
- Requires no oil changes for five full years, the lowest maintenance requirements in the industry.
- Fewer oil changes reduce waste stream and environmental impact.
- Independent tests prove Marley Geareducer is up to 12 dBA quieter than gearboxes used by other cooling tower manufacturers.
Fan motor is TEFC 1.15 service factor, horizontal–shaft motor designed to Marley specifications and specially insulated for humid cooling tower duty and extended life.
SofTork MC coupling
- Is specifically designed for Variable Frequency Drive (VFD) operation.
- Forgives minor misalignment between the motor and Geareducer.
- Absorbs excessive shock loads at start-up.
Five-year total mechanical equipment warranty includes mechanical equipment support and exclusive 5-year maintenance-free System 5 Geareducer.
Single inlet connection, either side or bottom inlet, and all piping from the inlet connection to the distribution basins are part of the NC Tower package.
Guardrail and ladder provide sturdy and stable access to the top of the cooling tower. Ladder safety cages and ladder extensions are available.
Mechanical access door platform
- Facilitates mechanical access.
- Includes internal ladder to elevated bar-grating platform with guardrail.
- Exterior platform with ladder and guardrail is available for outside motor option. Modular tower only.
Outside motor location
- Is easily accessible and protects motor from constant high humidity present inside the tower plenum.
- Includes Marley full-floating stainless steel driveshaft.
Variable flow distribution basins
- Allow significant variation in flow rates while protecting the tower from the disadvantages of poor water distribution, including icing, fill scaling and erratic performance.
- Permits staging of chillers and pumps while efficiently circulating water over all cooling tower cells.
- Dramatically reduces fan horsepower for a given heat load.
Factory-installed terminal control box provides a single location for all controls wiring.
Control systems range in sophistication from standard fan starters and disconnects, to programmable logic controllers that work in conjunction with process and building systems.
Variable speed drive provides advanced temperature control, energy management, sound control and mechanical equipment longevity.
Solid-state water level control package
- Monitors basin water level with solenoid-valve water makeup.
- Configurations include makeup with high and low water level alarm and cutoff, and electric basin heater cutoff.
Welded stainless steel collection basin
- All connection basin parts exposed to the circulating water are fabricated of heavy-gauge Series 300 stainless steel.
- Includes structural members projecting into basin, attaching hardware and all basin options including sumps.
Stainless steel distribution basin provides long, trouble-free service life where corrosion is usually most aggressive. Galvanized steel tower option.
Extended Geareducer oil line, located at fan deck level near the side of the tower, includes a dipstick to check oil level.
Air inlet screens
- Keep the tower interior free of leaves and debris.
- Factory-installed, U-edged, galvanized wire mesh screens mount over the air inlets.
- Horizontal frame design allows easy access to the collection basins.