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Fibreflow Cooling Towers Pty Ltd of 17

Project Issued {xx/xx/xx} Operation and Maintenance

™ OPERATION AND MAINTENANCE

FIBREFLOW COOLING TOWERS™

Copyright Fibreflow Cooling Towers P/L

Proudly Australian Owned and Manufactured

Member

™ FIBREFLOW COOLING TOWERS

Fibreflow Cooling Towers P/L of 17


CONTENTS

Note. This manual contains vital information for the Operation of Fibreflow Cooling Towers. Carefully read the manual before operation and all instructions must be followed. Save this manual for future reference.

OPERATION AND MAINTENANCE .................................................................................... 3

01 Preface. ............................................................................................ 3

02 Reference Publications. .................................................................... 4

03 Operation .......................................................................................... 4

04 Maintenance ..................................................................................... 5

05 TroubleShooting ................................................................................ 8

06 Spare Parts for Cooling Towers ........................................................ 9

07 Site Management .............................................................................. 9

MAINTENANCE SCHEDULE ............................................................................................ 11

08 Water Consumption In Cooling Towers ........................................... 12

APENDIX NO. 1................................................................................................................. 15

9 Reference Publications ................................................................... 15

APPENDIX NO. 2 .............................................................................................................. 17

10 Belt TenSion Forces ........................................................................ 17

WARNING AND DISCLAIMER

The information or advice contained in this document is intended for use only by persons who have had adequate technical training in the field to which it relates. The document has been compiled as an aid only and the information or advice should be verified before it is put to use by any person. The user should also establish the applicability of the information or advice in relation to any specific circumstances. While the information or advice is believed to be correct Fibreflow Cooling Towers Pty Ltd its employees, agents and consultants, disclaim any responsibility for any inaccuracies contained within the document including those due to any negligence in the preparation of the said document.




OPERATION AND MAINTENANCE

01 PREFACE.

The Fibreflow Cooling Tower Series have been designed to provide effective, efficient and economical cooling. In conjunction with adequate design, installation and commissioning of the associated cooling water system by the relevant parties, Fibreflow Cooling Towers will provide optimal performance. With regular maintenance and on-going site management, a long and effective service life can be achieved.

The reader of these Instructions will gain the benefit of extensive knowledge that that has been collected by technical personnel who have had in-depth experience over many years with a wide range of successful applications for cooling towers and the associated requirements. Application of this information will help ensure compliance and satisfactory operation and optimal performance to suit the particular needs of projects.

These Notes provide basic information covering the following aspects of water cooling systems:-

(i) Operation of cooling towers.

(ii) Maintenance/service of cooling towers.

(iii) Trouble-shooting

(iv) Site management of cooling water systems.

The Notes need to be read in conjunction with any requirements of the local authorities having jurisdiction concerning any relevant matters such as:-

Associated building work.

Electrical safety aspects.

Environmental and public health issues.

Environmental protection measures.

Occupational health and safety precautions.

Licensing of particular trade personnel.

Work of water supply, drainage and trade waste.

In respect of the relevant State or Territory of Australia, the requirements of the applicable principal legislation (e.g. Act) and secondary legislation (e.g. Regulation), can usually be obtained from the Internet at www.austlii.edu.au Enquire of the relevant authority as to the title for the applicable legislation.

These Notes are not exhaustive in detail and are subject to revision without notification.

A separate publication is available from Fibreflow Cooling Towers Pty Ltd covering system design and also the selection, sizing, installation and commissioning of cooling towers.

Feedback from readers would be welcome by Fibreflow Cooling Towers that could help enhance the application and use of these Notes

http://www.austlii.edu.au/




02 REFERENCE PUBLICATIONS.

The publications referenced in this document and listed in Appendix No1, are considered to be applicable to the operation, maintenance/service and site management of Cooling Towers. Attention to the matters covered by this document will help ensure correct operation and satisfactory performance of the water cooling system whilst helping to ensure compliance with relevant statutory requirements and thus minimise liability of the respective parties for any incident which may occur.

03 OPERATION

The references shown provide further information.

The strategy applied needs close attention to help ensure correct operation and satisfactory performance of the cooling tower in terms of the requirements for the project.

* AR denotes action required.

SERVICE AND PARTICULARS REFERENCE TO

REQUIREMENT/RECOMMENDATION

Mechanical Services

Cooling systems that have been shut-down on a seasonal basis or for more than 30 days, to be cleaned and water treatment reinstated before start-up.

AS/NZS 3666.2, Cls. 1.3, 2.5.4 and 2.6.1(c).

All drainage systems associated with the cooling water system to be flushed clear.

AS/NZS 3666.2, Cls. 1.3 and 2.5.1.

Measure and record the temperatures of the flow and return water and also the ambient wet bulb, preferably with a thermometer having 0.1º C graduations. Compare results with commissioning test data.

SAIA/SNZ HB 32, Sect. 6.11.3 (g).

Note any unusual noise or vibration and arrange service as necessary.

AS/NZS 3666.2, Cls. 1.3 and 2.5.1.

Note any leakage, splash-out or flooding of tower basin and arrange service as necessary.

AS/NZS 3666.2, Cls. 1.3 and 2.5.1.

Hydraulic Services

Check water level in basin against any marking and arrange service as necessary.

AS/NZS 3666.2, Cls. 1.3 and 2.5.1

Electrical Services

Note any visible overheating of motor or stoppage of fan and arrange service as necessary.

AS/NZS 3666.2, Cls. 1.3 and 2.5.1




04 MAINTENANCE

The references shown provide further information.

The strategy applied needs close attention to help ensure continued correct operation and satisfactory performance of the cooling tower in terms of the requirements for the project.

More frequent inspection and maintenance may be necessary where the tower is operating continuously and/or under harsh environmental conditions.

The high standard of construction and ease of maintenance of Fibreflow Cooling Towers simplifies the routine maintenance procedures including any prescribed cleaning and helps ensure continued satisfactory operation, optimal performance and maximum service life.

Prior to inspection and/or maintenance, the cooling water system should be shut down and the isolation switch tagged for safety reasons. The shut-down to be programmed and subject to prior approval of site owner/manager and other relevant contractors.

The tower should be maintained in good condition, as the installation may be subject to inspection at any time by the local authority.

SERVICE AND PARTICULARS REFERENCE TO


General

All inspection and maintenance/service personnel to wear appropriate personal protective equipment and comply with site safety procedures.

OH&S Reg.

AS/NZS 3666.2, Appendix A.

SAA/SNZ HB 32, Sect. 7.

When required by the local authority, all prescribed work of mechanical, electrical, plumbing/drainage and water treatment maintenance, is to be carried out by qualified personnel.

AS/NZS 3666.1, Cls. 1.3 and 1.5.15.

AS/NZS 3666.2, Cls. 1.3 and 2.2.1.

Mechanical Services

Visually inspect and clean where necessary all wetted/moistened surfaces of the tower including items such as fan and support, fan motor (externally), any attenuator, drift eliminator, any hot water basins, hot water distribution system, heat exchange fill or any condenser coil and support, internal tower casing, cold water basin/sump, air inlet/exhaust grilles, any internal walkway and also any air inlet and exhaust ducts.

The prescribed cleaning interval is not to exceed six months and the cleaning procedure to be site and item specific.

The cleanability and ease of cleaning of a Fibreflow Cooling Tower simplifies and expedites this process.

AS/NZS 3666.1, Cls. 1.3 and 1.5.12.

AS/NZS 3666.2, Cls.1.3, 2.5.1 and 2.6.1(c).

SAA/SNZ HB 32, Sects.6.11.3 (d) and (h).




Maintenance Continued

Check Tower and all components for any premature deterioration or physical damage and arrange service or repair or replacement as necessary

AS/NZS 3666.2, Cls. 1.3 and 2.5.1. Spare parts are available.

Check tower and any associated inlet and/or exhaust ductwork for any air or water leakage, undue noise or vibration and arrange service or repair as necessary.

AS 1055 AS 2659. AS/NZS 3666.2, Cls. 1.3 and 2.5.1. SAA/SNZ HB 32, Sect.6.11.3 (f).

Check the hot water distribution system within the tower for any blockage of nozzles or uneven distribution and service as necessary.

AS/NZS 3666.2, Cls. 1.3 and 2.5.1.

Check fan drive, belt tension and service as necessary.

Inspect keys, keyways and set screws and adjust as necessary.

Tighten any loose bolts.

AS 2784,Appendix B.

AS/NZS 3666.2, Cls. 1.3 and 2.5.1.

Belt tension forces are given in Appendix 2 of these Notes.

Check any gearbox for undue noise or vibration and arrange service as necessary.

AS/NZS 3666.2, Cls. 1.3 and 2.2.1.

Check condition of any physical access facility for tower and arrange service or repair as necessary.

OH&S Reg.

AS/NZS 3666.2, Cls. 1.3 and 2.2.3.

SAA/SNZ HB 32, Sect.6.11.1.

Check condition of any base or support frame for tower and arrange repair as necessary.

OH&S Reg.

AS/NZS 3666.2, Cls. 1.3 and 2.5.1.

Shell ‘Darina’ R2 high temperature grease or equal to be pumped into the fan shaft bearings via the external grease nipples provided until the grease squeezes out past both bearing seals. This is to be done whilst the bearings are turning. This action ensures that the old grease is purged whilst new grease is introduced into the bearing. Use low-pressure (hand operated) grease guns for this procedure to avoid premature damage to the bearing seals.

AS/NZS 3666.2, Cls. 1.3 and 2.5.1.

Any gearbox drive to be checked serviced and lubricated as per manufacturer’s instructions.

AS/NZS 3666.2, Cls. 1.3 and 2.5.1.

Check air-inlet and exhaust grilles are not blocked and that fan and motor function correctly. Service as necessary.

AS/NZS 3666.2, Cls. 1.3 and 2.5.1.

Check location and condition of sump thermostat and arrange service or replace as per the supplier’s instructions.

AS/NZS 3666.2, Cls. 1.3 and 2.5.1.

Provide required maintenance for any mechanical handling device used when manoeuvring fan, fan motor or any gearbox for maintenance purposes.

OH&S Reg.

AS 1418.1, Cl.16.3.

Check condition of any required OH&S and PPE safety signs on or near tower, for deterioration and arrange replacement as necessary.

OH&S Reg.

AS 1319, Cl. 4.3.

AS 1470, Cl. 10.6.4.

AS/NZS 3666.2, Cl. 1.3 and 2.2.3.




Maintenance Continued

Check condition of any labelling provided for identification purposes on cooling tower and any associated plant and equipment, for deterioration and arrange replacement as necessary.

OH&S Reg.

AS 1345.

AS 1470, Cl. 10.6.4.

Periodically review the operation and maintenance procedures for the particular cooling tower for effectiveness and revise as necessary.

SAI/SNZ HB 32, Sect. 6.11.3 (k).

Check that the Operating and Maintenance Manuals contain current information re the particular cooling tower and are readily available at the site for reference.

AS/NZS 3666.2, Cls. 2.6.2 and 2.6.3.

Electrical Services

Check speed, operation and condition of fan motor and service or replace as necessary.

AS/NZS 3666.2, Cls. 1.3 and 2.5.1.

Maintain any lightning protection system which forms part of the cooling tower.

AS 1768.

Hydraulic Services

Check the ball float valve in the make-up water line for correct operation and prescribed air-break and service as necessary. Renew the washer as necessary.

AS 2845.3, Cl. 1.1.

Provide any prescribed annual compliance report for the air-break on any ball float valve on the make-up water line.

CUPDR Code, Sect. 2.2.17 and

p 73.

AS 2845.3, Cl.2.1.

Water Treatment.

Review the maintenance/service reports for any advice regarding any deficiencies in the condition or operation of the cooling water system.

AS/NZS 3666.2, Cls.1.3, 2.6.1(e), 2.6.2 and 2.6.3.

System Cleaning

Review any reports for routine cleaning of system for any advice regarding any deficiencies in the condition or operation of the cooling water system.

AS/NZS 3666.2, Cls. 1.3, 2.6.1(e),2.6.2 and 2.6.3.

DURING WARRANTY PERIOD, A COPY OF THIS REPORT IS TO BE FAXED TO FIBREFLOW COOLING TOWERS PTY LTD




05 TROUBLESHOOTING

FAULT POSSIBLE CAUSE ACTION

Excessive Water Drift

(Rain effect)

Missing, displaced, or damaged eliminators.

Check to ensure all eliminators are present, correctly installed and free of damage.

Incorrect eliminators were fitted during any replacement.

Fit correct eliminators.

Over-pumping or under-pumping.

Reduce or increase water flow to tower design conditions.

Cold Water Too Warm.

Over-pumping Reduce water flow to tower design conditions.

Tower fill not level. Check fill with carpenters level

Transversely and longitudinally.

Tower fill not properly installed.

Check installation and spacing.

Not enough air. Check motor current and voltage to be sure of

correct rated kW.

Clean any debris from tower fill and

eliminators.

Recirculation of air from tower exhaust.

Improve ventilation for air inlet.

Tower not level. Check foundations for level (max. 3 mm in all directions).

Belt loose. Adjust or replace belt.

Unusual Motor Noise. Motor running single phase. Stop motor and attempt to start it. Motor will not start if single phase. Check controls, wiring and motor.

Electrical imbalance. Check voltages and currents of all three phases. Correct if required.

Faulty or worn bearings. Check lubrication. Replace any faulty or worn bearings.




06 SPARE PARTS FOR COOLING TOWERS

SPARE PARTS FOR COOLING TOWERS

(To be compiled)

Item Recommended Qty

Distribution nozzles 10

Fill blocks 10

Eliminators 2

Make Up Valve Assembly 1

Electric fan motor 1

Fan 1

Drive belts. 1 set Belt drive units only

Drive shaft and bearing assembly 1 assembly Belt drive units only

07 SITE MANAGEMENT

This information to be supplied to the site owner/manager for consideration in regards to the complete water cooling system of which the cooling tower is a part. The site management of cooling towers is important to help ensure their continued satisfactory operation and acceptable performance. Site management needs to check that legislative requirements are being met in respect of the operation and maintenance of the cooling water system and also that any operators and maintenance/service personnel are qualified for the work entailed. Administration of any associated maintenance contract or service agreement for the plant is another important role. The references shown below provide further information. Fibreflow Cooling Towers Pty Ltd can provide advice regarding any aspect of the on-going maintenance/service of the Towers to help ensure continued correct operation and satisfactory performance of the tower for the benefit of the end user. Arrangements can be made by Fibreflow Cooling Towers Pty Ltd for the tower to be maintained during the warranty period and for monthly reports to be supplied to site manager/owner.

Attention is drawn to the prescribed aspects of microbial control for other engineering services in buildings, which are covered by AS/NZS 3666.1 and AS/NZS 3666.2.

ROLE AND PARTICULARS REFERENCE TO


General Role of Site Management

Appoint a person who is managerially in control and who can arrange administration of any maintenance contract/service agreement or the supervision of any in-house maintenance by qualified personnel.

OH&S Reg.

AS/NZS 3666.2, Cl.1.3.

SAA/SNZ HB 32, Sect. 6.11.1.




Management should keep up to-date with the

substance and intent of the legal and regulatory

framework which applies to the site

management of maintenance of the

engineering services in buildings.

AS/NZS 3666.2, Cl. 1.3.

AS 3806.

SAA/SNZ HB 32, Sect. 8.1.

Managing Activities

Provide maintenance/service personnel with particulars of site safety and security procedures.

OH&S Reg.

AS 1470, Sect. 5.1.

AS/NZS 3666.2, Cls. 1.3 and 2.2.1.

Check that maintenance/service personnel are qualified for their activities.

AS/NZS 3666.1, Cls.1.3 and 1.5.15.

AS/NZS 3666.2, Cls. 1.3 and 2.2.1.

Check that client copy of monthly maintenance/service reports are complete, legible, signed and indicating compliance with maintenance/service requirements.

AS/NZS 3666.2, Cls. 1.3, 2.2.1, 2.6.2 and 2.6.3.

AS/NZS 3666.3, Cl. 3.7.


Periodically inspect plant and access for any obvious deficiencies or deterioration and inform the respective maintenance personnel.

OH&S Reg.

AS/NZS 3666.2, Cls. 1.3 and 2.2.3.

Seek advice on any necessary review of maintenance activities and also possible need for upgrading of system to help improve performance.

AS/NZS 3666.1, Cls. 1.3 and 4.1.5.

AS/NZS 3666.2, Cls. 1.3 and 2.6.1(e).

AS/NZS 3666.3, Cls.2.3 and 3.7.


ASHRAE HVAC Applications,

Chap. A38.

Ensure that the prescribed operating and maintenance manuals for the system, maintenance and service reports by the various contractors, are readily available on site for reference by relevant maintenance personnel and also for any inspection requested by an authorised officer, eg. Local council.

Note the authorised officer may request inspection of the system.

AS/NZS 3666.2, Cls.1.3 and 2.6.3.

SAA/SNZ HB 32, Sect.8.3.




MAINTENANCE SCHEDULE

Service

Monthly

Startup

Shutdown

Semi-annually

Inspect General Condition and Operation X X

Observe Operation of:

Mechanical equipment-motor, fan etc. X X

Makeup valve X X

Inspect and Clean as necessary:

PVC Drift eliminators X X

Collection basin X X X X

Fan motor exterior X X

Check:

Collection water basin level X X

Blowdown-adjust as required X X

Check belt drive system for:

Belt tension and condition X X

Sheave bushing fastener torque X X

Fan shaft bearing lubrication (every 3 months)

X X

Check and tighten as required:

Mechanical equipment structural bolts X X X

Motor anchor bolts X X X

Cooling tower framework structural bolts X X X

Fan assembly bolts X

Inspect metal surfaces and touchup X

Motor operation required (minimum) 3 hrs/mth




08 Water Consumption In Cooling Towers

The purpose of a cooling tower is to conserve water. It fulfills its purpose by rejecting heat to the atmosphere

by convective and evaporative heat transfer. As water cascades through the cooling tower, it comes into

contact with air that is pushed or pulled through the fill by mechanical draft fans. Some of the waste heat is

transferred from the warmer water to the cooler air by convection. The remainder of the heat is removed by

evaporation of a small percentage of the re-circulated water. The evaporation rate is determined by the

following equation:

Evaporation (E) = (0.0085) * (Recirculation rate, R) * (Temperature differential across tower, dT)

The water that is evaporated from the tower is pure; that is, it doesn’t contain any of the mineral solids that

are dissolved in the cooling water. Evaporation has the effect of concentrating these dissolved minerals in

the remainder of the tower water. If this were to occur without restriction, however, the solubility limit of the

dissolved minerals would soon be reached. When the solubility limit is reached, dissolved minerals (most

commonly calcium and magnesium salts) precipitate as an insoluble scale or sludge. This is the off-white,

mineral scale that is frequently found in heat exchangers, in the tower fill, or deposited in the sump.

To prevent the tower from over concentrating minerals, a percentage of the cooling water is discharged to

drain. The bleed or blow down rate is adjusted to control the concentration of dissolved minerals to just

below their solubility limit. This limit is commonly set and controlled by specific conductance (micromhos/cm)

or total dissolved solids (mg/l) measurements.

The water that is lost by evaporation and bleed must be replaced by fresh makeup to maintain a constant

system volume. Makeup is typically obtained from potable water sources, but it may also come from treated

wastewater or recycled water supplies (Figure 7):

Makeup (MU) = Evaporation (E) + Bleed (B) + Uncontrolled losses




One indicator of cooling tower efficiency is cycles of concentration, or concentration ratio. This is the ratio of

the makeup rate to the bleed rate, MU/B, assuming the uncontrolled losses are negligible.

Cycles of concentration are also estimated by the ratio of the specific conductance of the cooling water and

the makeup water:

Cycles of concentration (C) = MU / B

From these relationships, the amount of bleed required to maintain a specific cycle of concentration is

determined by:

B = E / (C – 1)

If E is held constant, reducing the bleed causes the cycles to increase. Conversely, increasing the bleed

causes the cycles to decrease. Operating the cooling tower at maximum cycles of concentration reduces the

amount of water sent to drain and thereby decreases the freshwater makeup demand. Overall, higher cycles

of concentration translate into greater efficiency as measured by a decrease in freshwater consumption and

wastewater discharge (Figure 8).

Cooling tower basics: Increasing the cycles of concentration or cooling tower water dissolved mineral

content will decrease the cooling tower blowdown and thereby decrease makeup water requirements.

However, increased minerals in the water can degrade tower performance over time. Source: Harfst and

Associates Inc.

The diminishing returns curve (Figure 8) indicates that major gains in water conservation can be achieved by

increasing the cycles from two to three. As we approach higher cycles, however, the incremental gains

decrease. From a practical view, windage, leaks, and other uncontrolled losses limit the cycles to a

maximum of about 10. This is a reasonable goal for most cooling towers and would further suggest that

cooling towers operating below 10 cycles of concentration are less than 100% efficient as measured by

makeup consumption and wastewater generation (see table).




Cooling tower efficiency is determined by cycles of concentration. The table data assume that 10

cycles of concentration represent 100% cooling tower efficiency for comparison purposes.

These figures suggest that cooling towers that operate at fewer than five cycles of concentration (less than

90% efficient) are not achieving their full potential and would benefit from retrofits that would reduce

freshwater consumption and decrease waste. Towers operating at six to eight cycles are acceptable for most

applications. Towers in the nine- to 10-cycles range have reached their peak. Achieving more than 10 cycles

would be difficult while deriving a reasonable return on investment, unless zero discharge is the ultimate

goal.




APENDIX NO. 1

9 REFERENCE PUBLICATIONS

The publications listed below are applicable to the operation, maintenance/service and site management

of Fibreflow Cooling Towers Pty Ltd.

Attention to these matters will help ensure correct operation and satisfactory performance of the water cooling system whilst aiming to ensure compliance with relevant statutory requirements and thus minimise liability of the respective parties for any incidents which may occur. The list is not exhaustive and is subject to revision without notice. There is a need to check for any revision of these reference publications.

I.Australian/New Zealand Standards/Handbooks:

These Standards are available from the local State Office of Standards Australia. AS 1006 (1995): Solid stem, general purpose thermometers. AS 1055 (1997): Acoustics-Description and measurement of environmental noise. AS 1319 (1994): Safety signs for the occupational environment. AS 1345 (1995): Identification of the contents of piping, conduit and ducts. AS 1470 (1986): Health and safety at work-Principles and practice.* AS 1768 (1991): Lightning protection. AS 2659 (1998): Guide to the use of sound measuring equipment. AS 2784 (2002): Endless wedge belt and V-belt drives. AS/NZS 2845.3 (1993): Water supply-Backflow prevention devices, Part 3-Field testing and maintenance. AS/NZS 3666.1 (2002): Air-handling and water systems of buildings, Microbial control, Part 1-Design, installation and commissioning.* AS/NZS 3666.2 (2002): Air-handling and water systems of buildings, Microbial control, Part 2-Operation and maintenance.* AS/NZS 3666.3 (2000): Air-handling and water systems of buildings, Microbial control, Part 3-Performance based maintenance for water cooling systems. * AS 3806 (1998): Compliance programs. SAA/NZS HB 32 (1995): Control of microbial growth in air-handling and water systems of buildings. * Referenced in most State legislation.

II. Mandatory Codes of Practice:

BCA 96: “Building Code of Australia”. ISBN 1 86264 875. Published by The Australian Building Codes Board, Canberra and referenced in legislation which is administered by the local building authority. The Code is available from the Australian Commonwealth Government Bookshops in the main capital cities. CUPDR Code of Practice: “NSW Code of Practice-Plumbing and Drainage”,(1999). Published by the CUPDR (Committee for Uniformity of Plumbing and Drainage Regulations in NSW) this operates within the NSW Department of Land and Water Conservation, Parramatta. ISBN 0-7310 6495 X

This Code is referenced in the legislation which is administered by the water supply and drainage authorities in NSW and is available from the NSW Government Information Bookshops in Sydney and Parramatta. The Code takes precedence over AS/NZS3500.1.2 and AS/NZS3500.2.2. Pages 41 and 62, detail the plumbing and drainage requirements for cooling towers.

III.NSW Health Circulars:




These Circulars are published by the NSW Department of Health and are available from the Internet at www.health.nsw.gov.au Circular No: 2001/36 issued 8 May, 2001:” Microbial Control “.

IV.Some General Reference Documents:

The following typical documents contain helpful information concerning water cooling systems. Other documents may need to be referred to for particular information.

a) AIRAH Publications:

Published by The Australian Institute of Refrigeration, Air-conditioning and Heating (Inc), Melbourne and referenced in AS/NZS3666.1.

Application Manuals DA17: Cooling Towers. ISBN 0 949436 18 6 DA18: Water Treatment. ISBN 0 949436 23 2 DA19: Maintenance of HVAC&R Systems (Includes cooling towers). ISBN 0 949436 25 9

b) ASHRAE Handbooks.

Published by The American Society of Heating, Refrigerating and Air-conditioning Engineers (Inc), Atlanta, USA and available from AIRAH. ASHRAE Handbooks:- “HVAC Systems and Equipment”, (2000)- Chapter 13 (Condenser Water Systems) and Chapter 36 (Cooling Towers). ISBN 1 883413 81 8 “HVAC Applications”,(2003)-Chapter 38(Operation and Maintenance Management). ISBN 1 931862 23 0

c) “NATSPEC Building and Services Reference Specification”. ISBN 0 9586187 6 3

Published by Construction Information Systems Australia Pty Ltd, Milsons Point, NSW and referenced in AS/NZS3666.1. Some relevant engineering services specifications:- Cooling Towers Mechanical General Requirements Water Treatment Mechanical maintenance

http://www.health.nsw.gov.au/




APPENDIX NO. 2

10 BELT TENSION FORCES Force Applied Mid-Span - 16 mm Deflection per Metre Span

Belt

Section

Small Pulley

Dia. mm

Lateral Force

Kg

SPA 100-132

140-200

2.5-3.6

3.6-4.6

SPB 112-224

236-315

4.6-6.6

6.6-8.7

SPC 224-355

375-560

8.7-11.7

11.7-15.3

Use a spring scale to measure the lateral force. Tests are to be carried out on each belt. Rotate the large pulley at least four times and recheck the tension. Repeat until the correct tension is achieved. On multiple belt drives, the average belt tension between the high and low figures should be made. It is recommended that belts from different manufacturers, not be mixed on the same drive. Wedge and V belts must not be mixed on the same drive. In order to avoid uneven distribution of load, belts running on a multiple belt drive, must be matched belts. AS2784 also includes important information in Appendix C regarding the storage and use of belts.