/ Marley AV Cooling Tower / User Manual 98-1514E
Contents Note This manual contains vital information for the proper installation and operation of your cooling tower. Carefully read the manual before installation or operation of the tower and follow all instructions. Save this manual for future reference. Tower Location........................................................................................ 4 Tower Shipment....................................................................................... 5 Receiving Tower.............................
Preparation The Marley AV Series cooling tower purchased for this installation represents the current state of the art in crossflow, induced draft cooling tower design. Thermally and operationally, it is the most efficient cooling tower of its class. These instructions—as well as those offered separately on motors, fans, float valves, etc.—are intended to assure that the tower serves you properly for the maximum possible time.
Preparation Note Those are only some of the safety issues that may arise in the design process. SPX strongly recommends that you consult a safety engineer to be sure that all safety considerations have been addressed.
Receiving and Hoisting Tower Shipment Unless otherwise specified, AV Series towers ship by truck (on flat bed trailers), which lets you receive, hoist, and install the tower in one continuous operation. Single-cell towers ship on one truck. Multicell towers, depending on their size, may require more than one truck. Responsibility for the condition of the tower upon its arrival belongs to the trucker—as does the coordination of multiple shipments, if required.
Installation Tower Installation Note These installation instructions are intended to help you prepare before your tower arrives. If discrepancies exist between these instructions and those shipped with the tower, the instructions shipped with the tower will govern. 1. Prior to placement of the tower, confirm that the supporting platform is level, and that the anchor bolt holes are correctly located in accordance with Marley drawings. 2.
Installation Note It is important that the cells be firmly anchored and aligned before the flume is attached to the 2nd cell. 7. Repeat steps 2 and 3 for 2nd top section on AV63000 thru AV67000 models. 8. Repeat steps 4 through 7 for any remaining cells. 9. Attach your cold water supply piping to the cold water basin outlet connection in accordance with drawing instructions, and utilizing gaskets provided by Marley.
Installation Normally, one of the following two inlet arrangements is provided: Standard distribution basin connections: There is a circular opening in the top deck of the tower near the air inlet face, drilled to accept standard 125# flat-face flange. Remove the center inlet flume assembly to gain access to attach inlet fasteners. (Refer to the AV Field Installation Manual shipped with tower.
Installation 10% higher than nameplate amps. High amps are common during tower commissioning when the tower is dry and the ambient air temperature is cool. • Do not start the motor more than six times per hour. Short cycling the tower will cause fuses, breakers or O.L.s to operate and will decrease motor life. When using a two-speed starter: • Motor rotation must be the same at slow speed and high speed. • Single winding motor requires a starter with a shorting contactor.
Installation ergy being used and provide better temperature control. In addition, it reduces the mechanical and electrical stress on the motor and mechanical equipment. Electrical savings can be large during periods of low ambient temperature when the cooling requirement can be satisfied at reduced speeds. To benefit from these advantages, it is important that the drive be installed correctly. Marley supplies VFD and VFD controls specifically designed for our cooling products.
Installation necessary, correct the alignment. See the Maintenance section for belt tensioning and sheave alignment—page 22. Warning Improper installation of the fan guard will destroy the structural integrity of the fan guard. It is essential that the fan guard be installed in accordance with the Field Installation Manual shipped with the tower. Do not force the fan cylinder out of round. 3. Momentarily energize (“bump”) the motor and observe rotation of the fan.
Operation Tower Start-Up Warning Among other sources, outbreaks of Legionnaires’ Disease have reportedly been traced to cooling towers. Maintenance and water treatment procedures that prevent amplification and dissemination of Legionella and other airborne bacteria should be formulated and implemented BEFORE systems are operated and continued regularly thereafter to avoid the risk of sickness or death. Water System: 1.
Operation balance the makeup water with tower operation. Ideally, the float valve setting will be such that no water is wasted through the overflow at pump shutdown. However, the water level after pump start-up must be deep enough to assure positive pump suction. 5. If a multicell tower installation is equipped with flow-control valves, adjust them to equalize hot water depth in the distribution basins after reaching design water flow rate.
Operation When biocidal treatment has been maintained at a satisfactory level for at least six hours, the fan may be turned on and the system returned to service. Resume the standard water treatment program, including biocidal treatment. Tower Operation General: The cold water temperature obtained from an operating cooling tower will vary with the following influences: 1. Heat load: With the fan in full operation, if the heat load increases, the cold water temperature will rise.
Operation order to prevent damage to the tower components. 4. Air flow rate: Reducing air flow through the tower causes the cold water temperature to rise. This is the approved method by which to control leaving water temperature. If your tower is equipped with a single-speed motor, the motor may be shut off when the water temperature becomes too cold. This will cause the water temperature to rise. When the water temperature then becomes too warm for your process, the motor can be restarted.
Operation Wintertime Operation: The Marley fill system used in the AV Series cooling tower has air entrance louvers that are molded integrally as part of the fill. This feature makes these towers very forgiving of cold weather operation, even at the low temperature and reduced load conditions encountered in free cooling and other low temperature applications. Nevertheless, during operation in subfreezing weather the opportunity exists for ice to form in the colder regions of the tower.
Operation produced by the entire tower would indicate. Wintertime operation of multicell towers at low cold water temperature levels requires that the operator be especially watchful. 2. As cold air enters the louvers, it causes the water flowing over the fill to be drawn inward toward the center of the tower.
Operation 4. With no heat load on the circulating water, icing cannot be controlled effectively by air control during freezing weather. Towers must not be operated with reduced water rate and/or no heat load during freezing weather. If the circulating water system cannot be shut down, water returning from the process should be made to bypass the tower. If a bypass is used, all water must be bypassed without modulation.
Operation Tower Cleaning, Water Treatment and Blowdown Maintaining Water Quality: The steel used in AV Series towers has been galvanized with a heavy zinc coating averaging 2.0 mils in thickness. AV Series towers are also available in stainless steel, which is even more corrosion resistant than galvanized steel in certain environments. Other materials used (PVC fill, drift eliminators, and louvers, aluminum fans, etc.
Maintenance Cooling Tower Cleaning: Warning Any evaporative-type cooling tower must be thoroughly cleaned on a regular basis to minimize the growth of bacteria, including Legionella Pneumophila, to avoid the risk of sickness or death. Service personnel must wear proper personal protective equipment during decontamination. Do NOT attempt any service unless the fan motor is locked out.
Maintenance concentrations. This stabilization of contaminant concentrations is usually accomplished by blowdown, which is the constant discharge of a portion of Cooling Range Number of Concentrations 1.5X 2.0X 2.5X 3.0X 4.0X 5.0X 6.0X 5° F (2.78° C) .78 .38 .25 .18 .11 .08 .06 10° F (5.56° C) 1.58 .78 .51 .38 .25 .18 .14 15° F (8.33° C) 2.38 1.18 .78 .58 .38 .28 .22 20° F (11.11° C) 3.18 1.58 1.05 .78 .51 .38 .30 25° F (13.89° C) 3.98 1.98 1.32 .98 .64 .48 .
Maintenance Sheave Alignment • The motor sheave is to be positioned as close as possible to the motor in order to minimize torque on the motor bushings. • The motor and fan sheaves may have grooves that are not used. The bottom surface of the motor and fan sheaves must be aligned within 1 ⁄8" of each other and level within 1⁄2° (1⁄8" in 12) in order to not adversely affect belt and sheave life.
Maintenance Schedule of Tower Maintenance Some maintenance procedures may require maintenance personnel to enter the tower. Each cased face of the tower has a door for access to the interior of the tower. All AV Series have a 30″ wide by 42″ high door opening. The purchaser or owner is responsible for providing a safe method for entering or exiting the access door. Protective clothing to avoid cuts from sheet metal should be worn. Wet sheet metal an/or dirt can be slippery.
Maintenance or worn out components. Use of high-pressure water may damage the eliminator and louver material. Observe operation of the float valve. Depress the operating lever to make sure that the valve is operating freely. Inspect the suction screen for plugging. Remove any debris that may have accumulated. Check for any buildup of silt on the floor of the cold water basin. Mentally make note of the amount, if any, so future inspections will enable you to determine the rate at which it is forming.
Maintenance Seasonal Shutdown Instructions When the system is to be shut down for an extended period of time, it is recommended that the entire system (cooling tower, system piping, heat exchangers, etc.) be drained. Leave the basin drains open. During shutdown, clean the tower (see Warning, page 20) and make any necessary repairs. Pay particular attention to mechanical equipment.
Maintenance lubricated before returning motor to service. Prolonged Shutdown If shutdown period is longer than seasonal, contact your Marley sales representative for additional information. SPX Cooling Technologies’ Services Our interest in your AV Series cooling tower does not end with the sale. Having conceived, designed, and manufactured the most reliable and longest-lasting cooling tower of its class, we want to make sure that you gain the maximum possible benefit from its purchase.
Maintenance Schedule Maintenance Service Monthly Semi-annually Seasonal Startup or Annually x x Mechanical–motor, fan and drive mechanism x x Makeup valve (if equipped) x x Inspect for unusual noise or vibration x x Air inlet x x PVC drift eliminators x x Distribution basin, nozzles and collection basin x x Fan motor exterior x x Collection water basin level x x Blowdown–adjust as required x x Inspect General Condition and Operation Observe Operation of: Inspect and Clean:
Troubleshooting Trouble Motor Will Not Start Unusual Motor Noise Cause Power not available at motor terminals • Check power at starter. Correct any bad connections between the control apparatus and the motor. • Check starter contacts and control circuit. Reset overloads, close contacts, reset tripped switches or replace failed control switches. • If power is not on all leads at starter, make sure overload and short circuit devices are in proper condition.
Troubleshooting Trouble Unusual Fan Drive Vibration Fan Noise Scale or foreign substance in circulating water system Cold Water Temperature Too Warm (See "Tower Operation") Excessive Drift Exiting Tower Cause Remedy Loose bolts and cap screws Tighten all bolts and cap screws on all mechanical equipment and supports. Fan Make certain all blades are as far from center of fan as safety devices permit. All blades must be pitched the same. See Fan User Manual. Clean off deposit build-up on blades.
Additional Information Increased load requirements: AV Series towers are designed such that cells of either equal or unequal capacity can be added in the future. This allows you to compensate for the load increases that normally occur with the replacement or addition of production equipment—and still retain continuity with respect to your cooling tower system. Tower rebuilding: SPX Cooling Technologies routinely rebuilds and upgrades cooling towers of all materials and manufacture.
7401 WEST 129 STREET | OVERLAND PARK, KANSAS 66213 UNITED STATES | 913 664 7400 | spxcooling@spx.com | spxcooling.com In the interest of technological progress, all products are subject to design and/or material change without notice. ©2008 SPX Cooling Technologies, Inc.
