This unit involves the skills and knowledge required to design complex air conditioning systems and select equipment.

It includes applying processes and methods of complex air conditioning systems, safety and relevant industry standards; developing alternative design schemes based on a design brief and customer requirements; and documenting system designs.

The skills and knowledge described in this unit may, in some jurisdictions, require a licence or permit to practice in the workplace subject to regulations for undertaking refrigeration and air conditioning work. Practice in the workplace and during training is also subject to work health and safety (WHS)/occupational health and safety (OHS) regulations.

No other licensing, legislative or certification requirements apply to this unit at the time of publication.

ELEMENTS

PERFORMANCE CRITERIA

Elements describe the essential outcomes.

Performance criteria describe the performance needed to demonstrate achievement of the element.

1

Prepare to design complex air conditioning systems

1.1

WHS/OHS requirements and workplace procedures for a given work area are identified, obtained and applied

1.2

WHS/OHS risk control measures and workplace procedures are followed in preparation for the work

1.3

Scope of the refrigeration system is determined from the design brief and/or consultations with relevant person/s

1.4

Design development work is planned in accordance with workplace procedure for timelines in consultation with others involved

2

Design complex air conditioning systems

2.1

Relevant complex air conditioning processes and methods are applied to the design

2.2

Alternative concepts for design are evaluated in accordance with the design brief

2.3

Safety, functionality and budgetary considerations are incorporated in the design specifications

2.4

System design draft is checked for compliance in accordance with the design brief and relevant industry standards

2.5

System design is documented for submission to relevant person/s for approval

2.6

Unplanned events are dealt with in accordance with problem solving techniques and workplace procedures

3

Obtain approval for complex air conditioning systems design

3.1

System design is presented to customer and/or relevant person/s

3.2

Requests for alterations to the design are negotiated with relevant person/s in accordance with workplace procedures

3.3

Final design is documented and approval obtained from relevant person/s in accordance with workplace procedures

3.4

Quality of work is monitored in accordance with workplace procedures and relevant industry standards

Evidence required to demonstrate competence in this unit must be relevant to and satisfy all of the requirements of the elements, performance criteria and range of conditions on at least one occasion and include:

developing outlines of alternative designs

developing the design within the safety, regulatory, functional requirements and budget limitations

documenting and presenting design effectively

successfully negotiating design alteration requests

obtaining approval for final design

dealing with unplanned events

applying relevant work health and safety (WHS)/occupational health and safety (WHS/OHS) requirements, including using risk control measures

designing complex commercial refrigeration system

preparing to design complex air conditioning system.

Evidence required to demonstrate competence in this unit must be relevant to and satisfy all of the requirements of the elements, performance criteria and range of conditions and include knowledge of:

complex heating, ventilation and air conditioning (HVAC) system design, safe working practices and relevant standards, codes and regulations, including:

HVAC load estimating of multiple zone and multi-storey buildings:

system design parameters:

human comfort

system requirements in accordance with AS 1668 The use of ventilation and air conditioning in buildings SAA refrigeration code

heat transfer calculations for complex structures and building components

heat and radiation transfer calculations through complex glass structures including various internal and external shading devices

indoor air quality

olfs and decipols

complex shading:

solar data, azimuth and altitude angles

shading from adjacent structures

computer software:

heat load estimating

building thermal performance analysis and simulation software

advanced psychrometrics:

complex psychrometric processes:

revise sensible cooling and heating and evaporative (adiabatic) cooling

cooling and dehumidification

cooling and dehumidification with high latent load

cooling and dehumidification all outdoor air

cooling and dehumidification all outdoor air with dehumidified air requirements less than supply air

cooling with evaporative humidification

cooling with near isothermal humidification

spray process to include cooling and dehumidification, cooling and humidification with heated spray water, heating and humidification

partial load processes

reheat

bypass of, RA only and mix of RA and OA

variable air volume

variable coil effective surface temperature

split coil, horizontal, vertical and intertwined

system performance:

saturation efficiency of sprayers

system capacity calculated from air quantity and enthalpy change

required plant capacity and airflow rates:

effects of coil bypass factor and ADP

calculation of dehumidified air quantity, using both TSH and ERSH methods

recap on psychrometrics formulae and charts:

properties of air

gas constants

derivation of air constants

combined gas laws

Dalton’s law of partial pressures

carrier’s equation

psychrometric property tables

psychrometric charts

air mixing equations

air quantity equations

indirect evaporative coolers

analysis of cooling coil selection and performance

psychrometric analysis of:

air conditioning in tropics

all outdoor air

LCV/HWF systems

psychrometric analysis using equations and tables

air conditioning system design:

design parameters for multi-storey building:

customer and objective

customer concept of environment desired

economic

client brief

relevant design criteria:

building purpose, location, orientation and shape

external environment ambient conditions

internal load diversity

thermal capacity behaviour

thermal load (full and partial)

zoning and building usage:

space and building

occupancies, single purpose and multi-purpose

system selection criteria:

economics

environment

control requirements

existing structures

new structures

system components

space for equipment and system

selection of appropriate system

system and applications:

design features, engineering procedures and controls

direct expansion - self-contained room/zone, heat pump, multi-zone fan-coils and central station

all water - room fan-coil

all-air - constant volume variable temperature, face and bypass, reheat, constant temperature variable volume, constant volume induction, dual-duct and dual-conduit

air water - induction unit and primary air fan-coil

HVAC energy conversation techniques:

heat recovery systems

night cycle

optimum stop/start

purge cycles

chiller/boiler/cooling tower sequencing

economy cycles (based on temperature or enthalpy)

supply air reset

supply water reset

condenser water temperature reset

power demand control

load limiting

load shedding

set point relaxation

ventilation cycles

plant - fixed OA to economy, boiler to electric reheat and constant volume to variable air volume (VAV)

cost-benefit (payback)

problem-solving techniques

relevant job safety assessments or risk mitigation processes

relevant manufacturer specifications

relevant WHS/OHS legislated requirements

relevant workplace budget, quality, policies and procedures

relevant workplace documentation.

Assessors must hold credentials specified within the Standards for Registered Training Organisations current at the time of assessment.

Assessment must satisfy the Principles of Assessment and Rules of Evidence and all regulatory requirements included within the Standards for Registered Training Organisations current at the time of assessment.

Assessment must occur in suitable workplace operational situations where it is appropriate to do so; where this is not appropriate, assessment must occur in simulated suitable workplace operational situations that replicate workplace conditions.

Assessment processes and techniques must be appropriate to the language, literacy and numeracy requirements of the work being performed and the needs of the candidate.

Resources for assessment must include access to:

a range of relevant exercises, case studies and/or simulations

relevant and appropriate materials, tools, facilities and equipment currently used in industry

applicable documentation, including workplace procedures, equipment specifications, regulations, codes of practice and operation manuals.

Foundation skills essential to performance are explicit in the performance criteria of this unit of competency.

Range is restricted to essential operating conditions and any other variables essential to the work environment.

Non-essential conditions may be found in the UEE Electrotechnology Training Package Companion Volume Implementation Guide.

Designing a complex air conditioning system must include at least the following:

one major component, including:

air handling plant

compressors

condenser

evaporators

circuits and/or systems

associated components and controls

Electrotechnology

Refrigeration and air-conditioning