AS NZS 5141:2018 pdf free.Australian/New Zealand Standard Residential heating and cooling systems – Minimum applications and requirements for energy efficiency, performance and comfort criteria.
2 Design
2.1 General
The prime elements of designing residential heating or cooling systems shall be as follows:
(a) Safety—
(I) system as installed is safe to operate and does not present a hazard; and (ii) work, health and safety conformance during installation and maintenance.
(b) Comfort for the occupants.
Indoor air quality.
(d) Energy efficient design and installation.
(e) Reduction of greenhouse gas and ozone depleting substances emissions.
(f) Noise level.
(g) Access for maintenance.
2.2 Design conditions
For the purposes of this Standard, the following design conditions shall be used:
(a) Outdoor design temperature conditions: Summer and winter outdoor temperatures: As per AIRAK and IRHACE DAO9 Air conditioning load estimation.
(b) Winter indoor temperatures: 21°C dry bulb room temperature at outdoor design temperature.
(c) Summer indoor temperatures: Refrigerated cooling 24°C dry bulb, 50 percent relative humidity room temperature at outdoor design temperature.
2.3 Heat load assessment
A heat load assessment shall be undertaken to provide a heating or cooling load estimate. The assessment shall include the following:
(a) Local climate [see Clause 2.2(a)] for outdoor design temperature conditions.
(b) Volume of the conditioned space, including floor area and ceiling height.
c) Window area, glazing, orientation with respect to the passage of the sun, and shading (inside and outside).
(d) Building fabric, including floors, ceiling and walls, partition walls to unconditioned spaces and the level of insulation.
NOTE Examples of conforming heat load calculators include the following:
(a) Computer-based heat load calculators that are recognized within the Australian heating and cooling industry.
(b) Form-based heat load tools from a recognized Australian air conditioning trade or professional body.
(c) See Appendix A for an example of a heat load calculation tool.
(d) Al RA H FAI RAI R http://www.fairair.com.au/
2.4 Selection and siting of equipment
2.4.1 General
Equipment (including associated air delivery system components) shall be selected to deliver the required heating capacity or cooling capacity and airflow that has been derived from the heat load assessment.
NOTE The requirements for the minimum airflow should be met without the dumping of excess air into an unconditioned space.
In addition, for gas ducted heaters, to minimize stratification and inadequate mixing of the room air, equipment shall be selected to ensure the minimum number of air changes per hour (see Table 1).AS NZS 5141 pdf download.