Delta TM-105312 User Manual

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PVC Solvent Cementing Instructions

The following procedure is recommended for the preparation and cementing of internal and external piping for Delta Cooling Towers:

Cut ends of pipe square using a handsaw and miter box. Tube cutters with wheels designed for use with PVC are acceptable, providing they do not leave a raised bead on the outside diameter of the pipe.

Use a chamfering tool or file to put a 10° to 15° chamfer on the end of the pipe. Lightly sand the area to be cemented to remove gloss. Using a clean rag, wipe pipe surface and fitting socket to remove dirt, moisture and grease. Acetone or similar solvent is recommended for cleaning.

Check "dry fit" of pipe and fitting by inserting pipe at least 1/3 of the way into the fitting. Position pipe and fitting to assure alignment. Pipe and fitting should be at same temperature condition.

Using a clean, natural bristle brush about 1/2 the size of the pipe diameter, apply a primer to the fitting socket. Apply primer with a scrubbing motion until the surface is penetrated. Primer should never be applied with a rag. Repeated applications may be necessary to achieve the desired dissolving action. In the same manner, apply primer to the pipe surface equal to the depth of the fitting socket, making sure the surface is well penetrated. Reapply primer to the fitting socket to make sure it is still wet.

While both surfaces are still wet with primer, use a clean brush to apply a liberal coat of solvent cement to the male end of the pipe. The amount should be more than sufficient to fill any gap. Next apply a light coat of solvent cement to the inside of the socket, using straight outward strokes to keep excess cement out of the socket.

While both surfaces are still wet with solvent cement, insert the pipe into the socket with a quarter-turntwisting motion. The pipe must be inserted the full length of the socket. The application of solvent cement to pipe and fitting, and the insertion of the pipe into the fitting, should be completed in less than one minute. If necessary, two persons should apply solvent cement to the pipe and fitting simultaneously.

Hold the joint together for approximately 30 seconds until both surfaces are firmly gripped. After assembly, a properly made joint will usually show a bead of cement around its entire perimeter. This should be brushed off. It is recommended that the joint be allowed to cure for 24 hours before pressure testing or operation.

Revised 1-8-2007

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Operation and Maintenance of Your TM Series Cooling Tower

Safety in Operation of the Fan

NEVER operate the fan when the access panel or the entire fan guard is removed.

NEVER remove access manhole cover while fan is in operation.

NEVER operate fan when any work, access, maintenance,trouble-shooting,etc. is being performed on the inside of the fan ring assembly or inside the tower plenum.

Normally, electrical codes dictate a disconnect box at the cooling tower.

The handle of the disconnect box must be locked in the off position and an OSHA DANGER tag

(DO NOT OPERATE) must be attached to handle securely.

Note: Removing fuses from the disconnect box may provide further assurance, but only when done by qualified personnel.

The foregoing precautions apply when any type of internal access to the tower is required, including the following examples:

Checking, maintenance or replacement of any fan assembly component.

Checking, maintenance or replacement of the water distribution system inside the tower.

Cleaning of the fill.

Any work that necessitates removal of any access door, the fan guard or the manhole cover.

Water Distribution System

Water distribution is accomplished by a low pressure, non-rotating,spray nozzle system designed to accommodate the specified flow rate.

IMPORTANT:

The flow rate of the cooling tower must be as close to the design gpm as possible. The water distribution system, including spray nozzles, is provided for the design flow condition. Under-pumpingorover-pumpingwill cause the cooling tower to perform inefficiently.

Design pressure at the inlet connection must be maintained for proper water distribution.

If the pressure is less or greater than the design, proper water dispersion over the internal wet decking will be impaired. If inlet pressure is low, water spray will not cover the entire wet decking surface. This causes channeling of air, and does not make maximum use of the heat transfer media. High inlet pressures will cause the water to over-spraythe wet decking media, hit the internal side walls of the tower shell and drop in a vertical flow along the shell walls without the opportunity for water / air contact through the heat exchange media. Excessive high spray pressure may also cause wet decking fatigue and damage.

The operating inlet pressure should be between 4.0 and 5.5 psi at the tower inlet.

Revised 1-8-2007

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The maximum operating inlet water temperature should not exceed 140° F.

CAUTION:

When stepping on top of the fill, distribute the body weight by means of two plywood plates as described earlier in these instructions.

Fan and Mechanical Drive System and Its Maintenance

Safety

Follow all safety instructions previously discussed.

Motor:

The standard motor is a totally enclosed motor , Class F insulation, 1.15 minimum service factor, epoxy coating on outside frame, and is specifically designed for cooling tower duty to the exclusive specifications of Delta Cooling Towers.

Should there be a problem with the motor, which may be covered under our standard warranty, the motor must only be inspected and serviced by an authorized motor manufactures warranty shop, and Delta Cooling Towers, Inc. must be notified, otherwise the warranty is void.

If the motor bearings have grease fittings, follow the lubrication recommendations as outlined in instructions from motor manufacturer. The majority of motors do not require greasing.

Start-upInstructions

Complete all start-upinstructions before applying heat load.

Clean any accumulated debris or packaging material from inside tower sump.

Check to be sure that the fan motor is properly wired for correct rotation as viewed from the top of the fan. Reverse leads will cause incorrect rotation and reverse direction of airflow.

Note: Fan rotation should always agree with rotation labels. Standard fan rotation is clockwise, (C.W.) however; non-standardfans may be designed to rotate counter clockwise, (C.C.W.)

Check for free rotation of the fan and fan blade tip clearance.

Fill the cooling tower sump or the cold water storage reservoir on gravity drain applications.

Water recirculation pump should be primed and all piping below the tower sump filled with water. Check pump for proper shaft rotation.

Start water recirculation pump and adjust flow to design. A flow metering device installed in the inlet is recommended but if not available, use the pressure differential across the pump in conjunction with the pump curve.

Revised 1-8-2007

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Check spray pattern from nozzles to be sure there is no clogging. Remove drift eliminators for nozzle inspection, then return to proper position.

Start up fan motor and check amperage and voltage against motor nameplate data.

The standard make-upvalve assembly is shipped with the plastic float ball strapped against the tower side to prevent damage. To set the ball for proper operation, loosen the screw in the fulcrum arm, lift or depress the arm with the plunger pressed against the valve seat and tighten. Repeat until the proper operating level is obtained (Refer to operating level table below). It is recommended that ashut-offvalve be installed in themake-upline.

After 24 hours of operation:

Check spray nozzles for clogging.

Check tower sump water level.

Water Level in Tower Sump

When the cooling tower is being operated with pump-suction,themake-upvalve assembly with float ball should be adjusted to set the water operating level as follows:

Tower Model #

Operating level (from

 

bottom of sump)

All Towers

10 inches

 

 

Access the make-upvalve through the window louver marked “Access Panel”.

A lower water level than recommended may cause air to be drawn into the tower outlet piping and cause pump "cavitation."

A water level higher than recommended will cause continuous overflow and waste of water as a result of potential “pull-down”from the piping when the system is shut down.

The overflow should NEVER be capped, or its elevation altered by raising external piping.

Note: On gravity drain cooling tower(s), make-upassembly, overflow, drain and vortex breaker are not provided.

Revised 1-8-2007

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Cold Weather Operation

Cold Weather Protection

The cooling tower may require protection against freezing at light heat loads when the wet-bulbtemperature is under 32°F., or during shutdown when the temperature drops below 32°F.

The following methods are recommended for use in Delta Cooling towers for protection during cold weather conditions. Recommended equipment is optional and may be ordered from the factory. Consult the factory for further information on which equipment to choose for your specific application.

Separate Indoor Sump

This method is virtually a foolproof antifreeze protection system with the added advantage of minimum maintenance. The indoor sump tank should be large enough to fill the entire recirculation system without danger of pump cavitation. As a general rule, the tank should be sized to hold three times the rate of circulation in gallons per minute (gpm).

The tank should be provided with properly sized overflow, make-updrain and suction connections. When a separate sump is ordered with a cooling tower, the watermake-upvalve assembly and the overflow and drain connections are installed in the indoor sump only.

When a sump tank is used, the cooling tower should be located high enough above it to allow free cold water gravity drain. A bottom outlet can be provided for gravity drain to indoor sump tank installations.

Reverse siphoning is a back flow of non-potable,recirculating water into a potable water system, which can occur through themake-upfloat valve assembly located in the water reservoir. Should the valve malfunction, blockage of the overflow or outlet lines would cause water level to rise in the reservoir, and themake-upwater pressure could drop below the atmospheric pressure creating a vacuum at themake-upinlet. Although precautions to prevent reverse siphoning are incorporated in the cooling tower design, we also recommend installing a check valve in the watermake-upsupply line, as a backup precaution.

Electric Immersion Heater

Cooling towers can be ordered with an anti-freezeimmersion heater systems, which consist of a 6KW heating element, water level sensor, adjustable thermostat and contactor. Components are factory installed, but will require field wiring.

Thermostatic On/Off Control

A thermostatically controlled fan for on/off operation, should be considered as an energy saving feature, for capacity control during winter operation. The thermostatic control can be field set to insure automatic fan shut-downwhen cold water drops below design temperatures, as well as fanstart-upwhen cold water rises to design temperature.

A thermostatic control provides excellent cooling tower anti-freezeprotection while reducing operating costs throughout cold weather operation.

Revised 1-8-2007

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PVC Distribution System

To prevent damage to the PVC distribution system during cold weather shut-down,install an automatic or manual drain line from the hot water inlet piping as close to the cooling tower inlet as possible. The entire inlet and distribution system must be drained forshut-downin subfreezing weather.

Piping

When the cooling tower is located outdoors, adequate measures including the use of heating tapes and insulation should be considered to protect water lines from freezing.

Operation at Sub-freezingAmbients

See Thermostatic On/Off control

1. Insure that the cooling tower is operating at the maximum possible heat load - An operating cooling tower will continuously extract heat from the circulating water. Without a heat load, the water will end up either at the air wet bulb temperature, or as ice, whichever occurs first.

2.Maintain Design Water Flow Rate Over The Fill - Reducing water flow over the fill area can produce semi-dryregions that are subject to rapid freezing.

3.Make sure a thermostat is installed to control fan operation to off at low cold-watertemperatures.

4.If tower is equipped with two speed motors, operate at low speed to increase leaving water temperature.

5.Cycle fans periodically to prevent ice from forming on louvers.

6.It may also be necessary to reverse fans for a short period of time to help melt ice by forcing warm water into tower.

De-energizethe fan(s) for two full minutes before reversing.

Reverse fan(s) no more than 2 minutes at a time (repeat as necessary). Extended reverse operation can cause ice to form on fan blades causing an out-of-balancecondition.

If the tower is equipped with a two-speedmotor, reverse only at low speed.

On multi-celltowers, fans immediately adjacent to reversed fans should be shut off during reversal.

After reversal, let fan(s) stand idle 5 to 10 minutes before forward operation.

Monitor the tower closely for unusual vibrations or sounds.

7.Frequent visual inspections and routine maintenance during sub-freezingoperation is very important and should not be overlooked.

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Trouble-ShootingGuide For TM Series

Induced Draft Cooling Towers

Problem

Possible Causes

Corrective Actions

Increase in the leaving water

1.

Excess water flow; over pumping.

1.

Adjust to the design flow.

temperature

2.

Recirculation of hot discharge air, back into

2.

Eliminate obstructions which impede air discharge.

 

 

the cooling tower air intakes. Obstructed air

 

For proper location of cooling tower(s), see Delta

 

 

intakes

 

dwgs. Baffle air discharge, if necessary.

 

3.

Proximity of other heat source or discharge

3.

Remove source or relocate tower.

 

 

of moist air.

4.

See water distribution system instructions.

 

4.

Improper operation of spray system.

 

 

A. Orifices clogged.

 

A. Flush spray nozzles, clean orifices, clean

 

 

B. Actual water flow is lower than design

 

system, install outlet strainer.

 

 

sprinkler rating.

 

B. Install properly rated spray nozzles or increase

 

 

 

 

to design flow.

 

5.

Clogged fill.

5.

Clean the fill.

 

6.

Damaged fill.

6.

Replace the fill.

 

7.

Additional heat load on system.

7.

Contact Delta for possible upgrade or addition of

 

 

 

 

another cooling tower selected for additional load.

 

8.

Wet-bulbtemperature higher than design.

8.

None required if condition is temporary. Otherwise

 

 

 

 

consult Factory for upgrade.

Drop in the water flow rate.

1.

Blockage of spray Nozzle orifices.

1.

Flush spray nozzle. Clean whole system. Install

Low water flow rate

 

 

 

outlet strainer.

 

2.

Low water level in sump causing air to be

2.

Adjust float valves. Be sure the system is flooded

 

 

drawn into pump and piping.

 

and balanced.

 

3.

Improper selection of water circulating

3.

Replace with proper size pump designed for flow

 

 

pump.

 

and head requirements. Check pump “Net positive

 

 

 

 

suction head.”

 

4.

Blockage of strainers.

4.

Backwash or clean.

 

5.

Pump malfunction.

5.

Consult pump specialist.

Noise and vibration

1.

Loose bolts.

1.

Recheck and tighten all bolts to specified torque.

 

2.

Mechanical interference of rotating parts.

2.

Inspect propeller for free rotation. Check propeller

 

 

 

 

for mechanical interference. Adjust, repair or

 

 

 

 

replace, as necessary.

 

3.

Fan propeller damaged or out of balance.

3.

Replace components, as necessary and check

 

 

 

 

balance. Install vibration cut-outswitch.

 

4.

Air intake at pump.

4.

Check basin water level and irregular piping design.

 

 

 

5.

Match pump NPSH with system hydraulics.

 

5.

Pump cavitation.

6.

Check and replace motor.

 

6.

Damaged motor bearings.

 

 

Sudden or short term irregularities of

1.

Peculiarities of specific system and its

1.

Inspect system and review operation procedures.

cold water level in basin

 

operation.

 

Correct, as applicable valve settings, loss of water in

 

 

 

 

system, fill system to flooded capacity.

Excessively high water level in sump on

1. Gravity flow restrictions due to insufficient

1.

 

gravity drain installation

 

head differential.

A. Outlet piping should terminate below sump tank

 

 

 

 

water level.

 

 

 

B. Increase discharge pipe size.

 

 

 

C.

Increase head by mean other than A.

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Problem

Possible Causes

Corrective Actions

 

2.

Airlock.

2.

Install an air bleed valve at highest point

 

3.

Unnecessary obstruction of waterflow

 

of piping, usually at a vertical angle.

 

 

(i.e., partially closed valve).

3.

Remove obstruction.

 

4.

Undersized piping.

4.

Increase pipe size.

 

5.

Horizontal pipe run too long.

5.

Shorten, if possible.

 

6.

Improper hydraulic pipe design.

6.

Correct design.

 

7.

Outlet vortex breaker provided.

7.

Remove vortex breaker.

Excessively high water level in tower basin

1.

Make-upvalve float set too high.

1.

Readjust float arm.

on closed loop system installations

2.

Valve or float damaged or

2.

Repair or replace.

 

 

malfunctioning.

3.

Reduce pressure or contact Delta for

 

3.

Make-upwater pressure too high.

 

 

 

 

alternate solutions.

Uneven water level in tower basins of multi-

1.

Unbalanced system hydraulics.

1.

A. Install equalizer line with isolation

cell installations

 

 

 

valves between modules.

 

 

 

 

C. Adjust inlet water flow to insure equal

 

 

 

 

distribution to each cooling tower

 

 

 

 

module.

 

 

 

 

D. Review outlet header hydraulics and

 

 

 

 

correct piping design, if applicable.

 

 

 

 

E. Contact Delta for assistance.

 

2.

More than one make-upvalve

2.

A. Adjust float level settings relative

 

 

operating, and set for different water

 

To one another.

 

 

levels.

 

B. Shut-offand or/throttle flow to

 

 

 

 

one or more valves.

 

 

 

 

C. Installation of equalizers is

 

 

 

 

highly recommended.

Excessive water carry over (drift)

1.

Surfaces of top layer of fill damaged

1.

Replace top layer. Protect fill when working

 

 

causing “pooling” of water.

 

inside tower.

 

2.

Eliminator(s) not in place.

2.

Reinstall.

 

3.

Damaged eliminator.

3.

Replace.

 

4.

Excess water flow.

4.

Reduce water flow or install spray nozzles

 

 

 

 

designed for the actual operating flow.

 

5.

Orifices in spray nozzles clogged

5.

Install outlet strainer. Clean whole system

 

 

causing improper water dispersement.

 

and spray nozzles.

 

6.

Blockage of fill.

6.

Clean fill.

Premature or excessive corrosion of fan

1.

Excessive drift.

1.

See “ Excessive Water Carry Over (Drift)”

drive components

 

 

 

above.

 

2.

Presence of corrosive chemicals in air

2.

Remove source of corrosion or contact Delta

 

 

or water that was not known at time of

 

for alternative materials, premium coatings

 

 

supply.

 

or other precautions.

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Motor Trouble Shooting Guide (General)

Problem

Possible Causes

Corrective Actions

High current draw (all 3 phases)

1.

Low line voltage (5 to 10% lower

1.

Consult power company.

 

 

than nameplate).

2.

Change to 230V motor.

 

2.

200V motor on 230/240V system.

 

3.

230V motor on 208V system.

3.

Change to 200V or 280V motor.

 

4.

Incorrect propeller.

4.

Consult factory.

 

5.

Incorrect pitch if adjustable

5.

Reduce pitch / consult factory

Low motor current draw

1.

Incorrect propeller.

1.

Consult factory

 

2.

Incorrect pitch if adjustable.

2.

Increase pitch / consult factory

Unbalanced current

1.

Unbalanced line voltage due to:

1.

Consult power company and/or

(5% from average)

 

A.

Power supply.

 

electrician.

 

 

B.

Unbalance system loading.

 

 

 

 

C.

High resistance connection.

 

 

 

 

D.

Undersized supply lines.

2.

Replace motor.

 

2.

Defective Motor.

Excessive voltage drop

1.

Inadequate power supply.

1.

Consult power company.

(2 or 3% of supply voltage)

2.

Undersized supply lines.

2.

Increase line sizes.

 

3.

High resistance connections.

3.

Check motor leads and other

 

 

 

 

 

connections.

Overload relays tripping

1.

Overload.

1.

Reduce load on motor or increase

 

 

 

 

 

motor size.

 

2.

Unbalanced input current.

2.

Balance supply voltage.

 

3.

Single phasing.

3.

Eliminate.

 

4.

Excessive voltage drop.

4.

Eliminate (see above).

 

5.

Frequent starting or intermittent

5.

Reduce frequency of starting and

 

 

overloading.

 

overloading or increase motor size.

 

6.

High ambient starter temperature.

6.

Reduce ambient temperature.

 

7.

Wrong size relays.

7.

Correct size per nameplate current

 

 

 

 

 

and service factor.

 

8.

Improper overload settings of

8.

Readjust to motor FL Amps x S.F.

 

 

adjustable relays.

 

 

Motor runs very hot

1.

Overloaded.

1.

Reduce overload.

 

2.

Blocked ventilation.

2.

Fouled fill or air restriction.

 

3.

High ambient temperature.

3.

Reduce ambient temperature.

 

4.

Unbalanced input current.

4.

Balanced supply voltage.

 

5.

Single phased.

5.

Eliminate.

Motor will not start

1.

Single phased.

1.

Shut power off – eliminate.

 

2.

Rotor or bearings locked.

2.

Shut power off – check shaft

 

 

 

 

 

rotation.

Excessive vibration (Mechanical)

Out of balance

1.

Check to be sure motor mounting

 

1.

Motor mounting.

 

 

 

 

 

hardware is tight.

 

2.

Motor.

2.

Replace motor.

Note: Consult Warranty page prior to replacing or repairing any cooling tower components. Delta recommendation and consent to remedy material and workmanship defects is necessary, to avoid breach of Warranty.

18

TM Series Optional Accessories

TM Series Optional Accessories Available

Aluminum Ladder(s) with a step platform and railing at the fan elevation custom designed for the cooling tower.

Safety cage(s).

Two speed motor(s) designed for cooling tower duty to the exclusive specifications of Delta Cooling Towers.

Vibration cut-outswitch provides for fan motor circuit disconnect for shutdown protection should abnormal fan vibration develop during service. Installation of vibrationcut-outswitchesare recommended as good design practice.

Thermostat on/off control of fan operation through sensing the temperature of water leaving the tower. Basin anti-freezesystem for cold weather operation.

Custom designed top platform with handrails.Pre-wiredcontrol panels.

Elevated mounting frame structures. Pumps

Polyethylene Sump tanks up to 2,000 gallons for indoor installation for anti-freezeprotection during winter operation.

Motor space heaters are recommended for unusually high relative humidity conditions where extreme day to night temperatures can cause excessive condensation in the motor, when in operation during this period. Plastic outlet sump strainer.

Plastic equalizer fittings.

Variable frequency drive on fan motors, controlled by temperature controller. High sump level switch

Automatic drain valve

Consult factory or a Delta representative for further information and an updated list of accessories.

TM Series Recommended Replacement Parts

To avoid costly cooling tower downtime, the following replacement parts should be carried in inventory at the installation site:

Make-upfloat, or completemake-upvalve assembly.

Cartridge of recommended moisture resistant lubricant.

Fan Motor.

Spray Nozzles.

When ordering, include model number and serial number of the cooling tower as it appears on the tower nameplate. Under normal conditions, shipment of factory replacement parts is made within one day after the order is received. Spare pumps and pump parts, as well as control panel components, such as fuses and heaters for magnetic starters, are also available.

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