Design Guidelines
Macquarie University Property
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Conditioning / HVAC

Mechanical Cooling and Heating

Mechanical cooling refers to the use of mechanical systems to provide cooling (and heating) for a space or building. Consider district cooling and/or heating provisions in the site for any new design.

Standard Specifications

The design of Space Conditioning Systems are to be in accordance with relevant Australian Standards and the MQP Mechanical Design Standards:


Installations will typically be checked against the MCL-01 Mechanical Works Checklist:



For related ITP's, methodologies, and Test report templates, refer to the Commissioning page.


The following components are to be assessed by the designer with consideration to individual space types.

Conditioned Space

A conditioned space is a space provided with air conditioning to meet set point requirements.

Ensure dehumidification in cooling mode is considered under full and part load conditions for any new design.

Tempered Space

A tempered space may be provided with a level of mechanical cooling or heating to marginally treat or "temper" supply air into a space. Setpoint levels are unlikely to be the main factor for consideration – supply air temperature or temperature difference from ambient may be key factors in design.

Consider effects of tempering on relative humidity levels in supply air in any new design.

Unconditioned Space

An unconditioned space is not provided with mechanical cooling or heating.


Controls systems include full building management and controls – including interface with non-mechanical services. Refer to BMS guidelines.

Reed Switch To Openable Windows / Louvres

Reed switches may be required on operable windows in conditioned spaces to enable switching of air conditioning zones in response to façade elements being opened.

Standalone Conditioning

This refers to a conditioning system that is not linked with other systems in the building or site. It usually infers DX type package or split systems that require power only to operate.

24/7 Operation

Some systems may be required to operate continuously (24/7). Consider operation of thermal plant when selecting systems that require 24/7 operation.


Tolerance of systems may be nominated for specific systems and/or spaces.

Space Conditioning Other

Humidity Control

Humidity control refers to an actively controlled system whereby humidity is measured and control systems are in place to meet a targeted set point. Note that dehumidification is a by-product of the cooling process only and is not considered humidity control. Consider energy efficiency carefully in any humidity control application.

100% Redundancy

Redundancy of systems may be required for critical applications. Consider all failure points when designing overall system to avoid duplicated equipment with single point of failure.

100% redundancy refers to provision of 100% spare capacity as back up (N+N)

Duty / Standby

Duty/Standby systems are often included in designs as a means of redundancy. Typically the duty unit (fan, pump) would alternate between the nominated items on a regular basis. Ensure isolation and removal of each element is possible with alternative items running.

Heat Recovery

Heat recovery systems can be employed to reduce energy consumption of high outside air loads. System may be sensible only or full enthalpy air-to-air system. Air-to -fluid systems may be applicable in some circumstances.

Consider corrosion and cross-contamination when selecting systems/components.