Cooling towers and evaporative condensers form an integral part of the refrigeration system - in commercial, industrial and air conditioning fields. The towers, condensers, centrifugal water pumps, fans, valves and controls comprise the maintenance/repair work skills relevant to this field and must be assessed in this context.

Demonstration of competency must be in accordance relevant Australian standards, regulations and codes.

Where water treatment only is required, then revised MEM13007B (Maintain water treatment systems for cooling towers) should be considered.

Where the refitting or repair/replacement of components involves the fabrication and installation of pipework and assemblies, Unit MEM10010B (Install pipework and pipework assemblies) should be accessed.

Where any rectification, modification involves electrical disconnection and reconnection, then Unit MEM18049C (Disconnect/reconnect fixed wired equipment up to 1000 volts a.c./1500 volts d.c.) should also be selected.

Band: A

Unit Weight: 4

Path 1

MEM05006C

Perform brazing and/or silver soldering

MEM09002B

Interpret technical drawing

MEM12002B

Perform electrical/electronic measurement

MEM12023A

Perform engineering measurements

MEM18001C

Use hand tools

MEM18002B

Use power tools/hand held operations

MEM18055B

Dismantle, replace and assemble engineering components

MEM18086B

Test, recover, evacuate and charge refrigeration systems

MEM18094B

Service and repair commercial refrigeration

Path 2

MEM05006C

Perform brazing and/or silver soldering

MEM09002B

Interpret technical drawing

MEM12002B

Perform electrical/electronic measurement

MEM12023A

Perform engineering measurements

MEM18001C

Use hand tools

MEM18002B

Use power tools/hand held operations

MEM18055B

Dismantle, replace and assemble engineering components

MEM18086B

Test, recover, evacuate and charge refrigeration systems

MEM18088B

Maintain and repair commercial air conditioning systems and components

ELEMENT

PERFORMANCE CRITERIA

1. Undertake preventive maintenance checks

1.1. Legislative requirements are understood.

1.2. System components are identified.

1.3. The operational function of each component is inspected and tested.

1.4. Correct operation of each component is assessed against specification.

1.5. Visual inspection and testing with appropriate test equipment is carried out according to refrigeration principles, procedures and safety requirements.

1.6. Preventative maintenance tasks are performed to manufacturers' specifications using refrigeration techniques and practices.

2. Undertake fault finding on cooling tower/evaporative condenser water systems components

2.1. System components are identified correctly.

2.2. The characteristics and operation of each component is understood.

2.3. The operational function of each component is inspected and tested.

2.4. Correct operation of each component is assessed against specification.

3. Repair/replace cooling tower/evaporative condenser components

3.1. Faulty components are localised and malfunction is confirmed by inspection and testing using refrigeration principles, procedures and safety requirements.

3.2. Faulty components are dismantled and repaired to manufactures' specifications as required.

3.3. Replacement parts are selected from manufacturers' or other catalogues according to required specifications.

3.4. Where required, refrigerant is removed/contained following refrigeration principles and procedures to all relevant standards, codes and safety standards.

4. Return to service cooling tower/evaporative condenser components.

4.1. Components are reassembled and tested for correct operation and assessed against specification.

4.2. Where required, refrigerant is added to system, following refrigeration principles and procedures to all relevant standards, codes and safety standards.

4.3. Using refrigeration principles and system application, correct operation of the equipment is verified.

4.4. Maintenance records/service reports are completed by appropriate designated means.

Required skills

Look for evidence that confirms skills in:

using tools, techniques and equipment necessary to check cooling tower/evaporative condenser fans, valves, centrifugal pumps and components for correct operation

obtaining and interpreting specifications

comparing system and component performance/operation against specification

identifying faulty components and non-compliances

making required adjustments to achieve specifications

sourcing and using relevant catalogues/lists

removing and replacing refrigerant

applying safety procedures, standard operating procedures and legislative requirements to all work undertaken

documenting results of the adjustments

Required knowledge

Look for evidence that confirms knowledge of:

terminology of cooling towers

psychometrics

measuring instruments/equipment, specifications and procedures for checking temperature(s)/humidity/air flow

operation of centrifugal water pumps

terminology of centrifugal water pumps

field testing centrifugal pumps

operation of water valves including bypass valve either mechanical or electrical operation

procedures for testing and operation of controls

procedures for testing of fan motors

v belts

measuring instruments/equipment, specifications and procedures for checking component noise and vibration levels

procedures for reporting non-conformances

procedures and sequence for performing preventative maintenance on refrigeration and air conditioning systems

specifications, operational characteristics and process for identifying system components

process for localising and confirming faulty components

procedures and all legislative and regulatory requirements for safely removing the refrigerant and charging the system

procedures for dismantling, repairing, reassembling and testing components

procedure for removal/recharging refrigerant

procedures for selecting replacement parts

procedures for completing maintenance records/service reports

The evidence guide provides advice on assessment and must be read in conjunction with the performance criteria, required skills and knowledge, range statement and the Assessment Guidelines for the Training Package.

Overview of assessment

A person who demonstrates competency in this unit must be able to maintain and repair cooling towers and/or evaporative condensers, fans, centrifugal water pumps, valves and control equipment. Competency in this unit cannot be claimed until all prerequisites have been satisfied.

Critical aspects for assessment and evidence required to demonstrate competency in this unit

Assessors must be satisfied that the candidate can competently and consistently perform all elements of the unit as specified by the criteria, including required knowledge, and be capable of applying the competency in new and different situations and contexts.

Context of and specific resources for assessment

This unit may be assessed on the job, off the job or a combination of both on and off the job. Where assessment occurs off the job, that is the candidate is not in productive work, then an appropriate simulation must be used where the range of conditions reflects realistic workplace situations. The competencies covered by this unit would be demonstrated by an individual working alone or as part of a team. The assessment environment should not disadvantage the candidate.

This unit could be assessed in conjunction with any other units addressing the safety, quality, communication, materials handling, recording and reporting associated with the maintenance and repair of cooling towers/evaporative condensers /pumps/ fans or valves, or other units requiring the exercise of the skills and knowledge covered by this unit.

Method of assessment

Assessors should gather a range of evidence that is valid, sufficient, current and authentic. Evidence can be gathered through a variety of ways including direct observation, supervisor's reports, project work, samples and questioning. Questioning techniques should not require language, literacy and numeracy skills beyond those required in this unit of competency. The candidate must have access to all tools, equipment, materials and documentation required. The candidate must be permitted to refer to any relevant workplace procedures, product and manufacturing specifications, codes, standards, manuals and reference materials.

Guidance information for assessment

The range statement relates to the unit of competency as a whole. It allows for different work environments and situations that may affect performance. Bold italicised wording, if used in the performance criteria, is detailed below. Essential operating conditions that may be present with training and assessment (depending on the work situation, needs of the candidate, accessibility of the item, and local industry and regional contexts) may also be included.

Components

Fan motor, fan blade, pump, pump motor, sprays, condenser, valves (bypass, shut-off, temperature control valves), thermostat, drift eliminators, v belt, water strainer

Operational

How it works

Test equipment

Sling psychrometer, thermometer, refrigeration gauges, vacuum pump, leak detector, multimeter, insulation resistance tester, assorted hand tools

Manufacturers' specifications

Details supplied by manufactures

Characteristics

The design and installation of the particular component

Malfunction

Could be a fault in any of the components

Type of installation or equipment

Unit sector

Maintenance and diagnostics

This unit contains employability skills.