EvapORATIVE CoolING Split SysTEM

8/11/2019 EvapORATIVE CoolING Split SysTEM

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PLUMBING INDUSTRY COMMISSION

7 : M E C H A N I C A L S E R V I C E S

Current as at March 2001

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Evaporative Coolers

Drainage provisions forevaporative coolers

The discharge pipe from an evaporative cooler must besized in accordance with the manufacturers requirementsand must have continuous fall to the termination point.

The discharge pipe must have an internal diameter of noless than the internal diameter of the unit connectionprovision supplied by the manufacturer.

The following diagrams are typical and provide guidancefor evaporative cooler installers on the permitted ways todischarge the drains from evaporative coolers in accordancewith the Plumbing Standards Regulations.

1. A discharge point to aroof gutter pop outlet,providing the downpipeis not used for thecollection of waterfor potable use.

150mm min150mm min.Drain to dischargeover pop to preventponding in gutter

Downpipe

Drain

EvaporativeCooler

3. A surface stormwater drainage system.Provided the surface is graded awayfrom the building and ponding doesnot occur, and the discharge does notpresent a safety risk to pedestrians(eg. across a footpath).

Tundish

Sealed connection

Downpipe

EvaporativeCooler

Air gap 25mm

2. Direct to a downpipevia a tundish, providingthe downpipe is notused for thecollection of waterfor potable use.

Stormwater pit

Surface graded to pit

Drain

4. A sanitary drainage system via a tundish in one of thefollowing forms in accordance with AS/NZS 3500.2.2 1996 clause 4.6.7.8 & 11.22

4 (a) To a disconnector gully.

Drain

Air gap 25mm

DG

40mm trappedwaste 3.5 max.

or50mm trappedwaste 6m max.

Drain

Air gap 25mm

FWG riser Untrapped waste DN 25max. length 10m

4 (b) To a floor waste gully.

Technical SolutionsTechnical SolutionsTechnical Solutions


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Drain

Stormwater drain

Absorption pit

Earth cover

Stone, brick orlarge granular material




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4 (c) Direct to a sanitary drain.

Evaporative Coolers Cont.

Drain

Air gap 25mm

40 or 50mmtrapped waste

2.5m max. to a direct connection

min. 65mm drain

Drain

Air gap 25mm

40 or 50mm trapped waste2.5m max. to a stack

5. An absorption pit. Provided the following conditions canbe met:

Only permitted where no sanitary or surface waterdrainage is available.

The pit can only be constructed in permeable ground. Of a size appropriate for the volume of discharge. Located so the discharge water will

not cause damage to buildings bychanging moisture conditions.


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Drain

Indoor Unit300mm

min.

downpipe

Angle cut to allowfor downpipeblockage

Drain

Sealedconnection

Downpipe

Bend one pipesize bigger thandrain




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Split System Air Conditioning


Condensate drainage forsplit system air conditioners

Drain Material

The material used for the drain must be suitable for thepurpose and if a plastics material is used it must be of a typesuitable for installation in direct sunlight.

Pumped Condensate

If condensate from an indoor unit has to be pumped toits drainage termination point it is essential that the pump isinstalled in an accessible position for service/maintenancepurposes.

Termination points

The following diagramsprovide guidance on the

approved methods ofdischarge for condensatedrains from split system airconditioning.

1. On to a garden bed.

2. Concrete or paved surface.Provided the surface isgraded away from thebuilding and ponding doesnot occur, and thedischarge does not presenta safety risk to pedestrians(eg. across a footpath).

Drain

Garden bed

Indoorunit

Drain

concrete or pavinggraded away from building

Indoorunit

3. To a downpipe provided the following two points areobserved;(a) Provided there is a form of disconnection to prevent

leakage into the building from the indoor unit ifthere is a blockage in the downpipe. Figs 1 & 2.and

(b) The connection to the downpipe is a minimum of300mm below the drain outlet of the indoor unit.Fig 3.

Top of tee left opento allow for downpipeblockage

Short sectionof pipe

Drain

Sealed connectionDownpipe

Fig 1

Fig 3

Fig 2


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Drain

Air gap 25mm

FWG riser Untrapped waste DN 25max. length 10m




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Split System Air Conditioning Cont.

4. To a down pipe via a lower metal roof.

Discharge directlyover downpipe pop

Drain

Indoorunit

Continued ... /

Placement of an outdoor unit on a metaldeck roof.

The following provides guidance for the installation ofsmall domestic size outdoor units on a metal deck roof.

You must ensure that the weight of the unit is notexcessive for the design of the roof structure.

Larger units may require engineering computations toensure adequate strength of the roof structure.

If timber is to be used as a support material on a metal roofit should be redgum to minimise the possibility of stainingthe roof as it weathers. The redgum can be painted ifnecessary to further protect the timber and the roof.

It is not permitted to install timber bearers in thetray section of a steel deck roof as support for anoutdoor unit as the flow of water in the tray isimpeded.

Metal deck roof Roof drainage reducedby timber bearer

5. A sanitary drainage system via a tundish in one of thefollowing forms in accordance with AS/NZS 3500.2.2 1996 clause 4.6.7.8 & 11.22.

5. (a) To a fixture trap provided the connection is above thelevel of the water seal and the top of the tundish isabove the overflow level of the fixture.

5. (b) To a floor waste gully.

Drain

25mm Air gap

Tundish


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Split System Air Conditioning cont.


If timber bearers are to be used as a support ensure theyare placed on top of the ribs and insulated from the metalby a suitable material (eg rubber waffle pads) to preventcorrosion occurring.

Metal deck roof

Timber bearer

Insulation

Placement of an outdoor unit at groundlevel.

An outdoor unit should be mounted level on appropriateconcrete slabs and secured by means of suitable brackets toan adjacent wall.

Bracket secured to wall

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EvapORATIVE CoolING Split SysTEM