1. INSTALL AND MAINTAIN EVAPORATIVE COOLING SYSTEMS
CPCPMS3010A

2. Safety
Occupational health and safety (OH&S) requirements need to be observed in accordance with legislation.. You need to know the OH&S laws governing your job. Revision of BCPCM2003A – Carry out OH&S requirements, before commencing this unit is advisable
overalls – used for the protection of the installer when working in different conditions
boots – it is recommended that soft soled footwear is worn while working on roofs, as deep grooved footwear pick up small stones and debris that might damage or scratch the roof sheets
safety glasses or goggles to protect the eyes from injury when cutting the sheets with a power saw
ear plugs or muffs to protect the installer’s hearing from excessive noise
dust masks or respirators to protect the user from breathing in dust or fine particles when cutting the sheets with a power saw
gloves, for the protection of the installer’s hands when working with different types of pipes, tools and equipment.

3. EVAPORATIVE COOLERS HOW THEY WORK.
Warm air is drawn through the dampened wet pads
Water is evaporated into this air stream cooling & humidifying it.
This cool humidified air is distributed through the house or building via a system of ducting.
For an evaporative cooling system to work efficiently adequate ventilation must be provided.
This means doors and windows need to left ajar or open for the effective flow of air to exhaust.
E.g. approx. One M2 of open area is required for each cubic M per /sec 2 of air that the unit is delivering.

4. EVAPORATIVE COOLERS WHERE ARE THEY MOST EFFECTIVE.
They are generally use in areas of low humidity or moisture content in the air .
E.g Hot Dry heat is best , Not Queensland.
If the outside air is relatively humid already then the cooling effect is limited.
As a guide the average relative humidity for Sydney is between 60 & 70 % in summer, while in Orange it is between 40 & 50%, while evaporative cooling would work in both these areas it operates more effectively in Orange due to the lower humidity .
In the Bendigo and surrounding areas this noticeable on hot & humid muggy days when evaporative cooling is not as effective.

5. EVAPORATIVE COOLERS SIZING GUIDELINES
Sizing is based on the following factors
Air Flow required to each room & the total air flow required.
The area you live climatic limitations may apply.
The rate of air required is specified as the litres per /second or cubic metres per/ hr.
Select a cooler with the ability to fill the entire building with air every 1.5 to 2 minuets .
To calculate volume simply multiply the floor area by the ceiling height.
E.g. 200 m2 area with a 2.5 mtr high ceiling = 500 m3
If we multiply that by 2 air changes we would require a unit that can deliver 1000m3
Always check with the manufacturer for the sizing recommendations for the region you live.

6. EVAPORATIVE COOLERS TYPES OF COOLERS AVALIABLE.
Portable Units , require standard power outlet , position near open door or window, need to be filled with water regularly or hose connected. Up to 25m2
Fixed Room Unit, Permanently plumbed & wired , installed on external walls. Up from 30 to 50m2
Ducted House or Central Systems, Roof mounted , permanently wired & plumbed, existing heating ducts are smaller are generally not used for cooling, cool air is supplied via a series of insulated ducts & registers to each room or to a plenum box for commercial jobs.

7. EVAPORATIVE COOLERS CONSIDERATIONS.
Locate the unit where it is not an eye sore or noticeable .
On high humidity days run the unit on its highest fan setting with the pump turned off.
Always ensure enough air can expel from operable doors or windows , if the air cannot escape the humidity in the room will increase and make it uncomfortable.
During winter roof mounted units should be covered to reduce the loss of heat , or alternatively close the ceiling registers .
Roof mounted units are required to be a minimum of 5 metres clear of any drainage vent.
Water consumption will vary depending on the day a typical unit may use approx. 10ltrs per/ hr on a 35 degree day, while on a 40degree day the same unit may use up to 25 ltrs per/hr .

8. EffICENCY
We need to understand the difference between Wet & Dry Bulb Temperature before we can understand efficiency.
Dry Bulb is the temperature obtained by a typical thermometer .
Wet Bulb is the temperature reads the humidity in the air in relation to the dry bulb temperature.
This reading is taken with a sling thermometer which has a moistened wick, the thermometer is spun around to take a reading of the air as it is moving.
This reading will be lower than the D.B temperature due to the evaporating effect of the air passing over the moistened wick.

9. Efficiency
The difference between the Dry Bulb & Wet Bulb temperature is always dependent on the moisture content of the air or relative humidity ,simply put the more humid the day the less effective the cooling.
The efficiently of the cooler is defined as the drop of Dry Bulb temperature air trough the cooler divided by the Wet Bulb depression of the entering air .
This should be approximately between % for wetted pad coolers

10. Sizing of installations
The ideal size of an Evaporative Cooler depends on:
Climatic Conditions (Where you live)
The type of home insulation & shading.
The internal heat load of the building. ( e.g. Amount of glass facing west)
There should be approximately 30 air changes per hour in the area to be cooled or as mentioned earlier the unit should be capable of filling the entire building with air every 1.5 to 2 minuets .
The air velocity through ducts should not exceed 10 metres per second ,velocity will create noise at the registers.
If sized correctly the air noise will be unnoticeable and the occupant will feel air movement.

11. Unit construction
Large units can be fabricated around a frame incorporating slip fit panels for filters over a waterproof sump.
The sump houses the cold water makeup ball float valve, overflow and re-circulating pump.
These types of coolers usually incorporate a two speed or variable speed control for the fan so air volume can be varied.
A pump switch allows the unit to respond to varied conditions.

12. Unit construction
Evaporative coolers consist of the same basic components.
Filter Medium or pads
Pump
Sump
Fan axial or drum
Control module or board.
Water distribution system
Bleed off & dump system

13. Evaporative cooling system
The installation for a domestic dwelling consists of a steel duct that is mounted vertically through the roof structure.
The unit is mounted on the top of a vertical duct. Flexible ducting is connected to the vertical duct and extends to the ceiling diffusers
Experience shows that it is better to duct cool air directly to each room rather than have just one or two outlets.
Diffusers should be placed away from the windows to limit areas where there is reduced airflow.
The unit should be mounted above a bathroom or laundry to keep any noise away from living areas.

14. Occupational Health and safety
When working on any task you must observe the regulations and OH&S requirements in accordance with state or territories legislation. You need to be aware of OH&S laws governing your job.
Installation may require the following activities:
Working on roofs of buildings.
Take care that fall protection measures are taken. This could mean the usage of lifelines and harness, perimeter guardrails or scaffolding
Ladders should be in good condition, Inclined at 1:4, Tied at the top ,Seated squarely on the ground
The use of scaffolds or elevated platforms may need trained operator

15. Occupational Health and safety
The use of hand and power tools.
Use earmuffs and eye protection.
Use the appropriate tool for the job.
Power tools and leads must be tagged.
Beware of hazards like the presence of water.
Lifting and moving large and or heavy objects.
Use trolleys or rollers.
Crane.
Activity should be planned to avoid damage or injury.
Handling insulation materials.
Avoid contact with bare skin.
Use a respirator.

16. Preparation for installation
The following things need to be known:
Location of existing water supply
Location of electrical services
Location proposed for cooler controller
Size of rooms and ceiling height
Access to site
Type of roof covering.
Available roof space.
Position of drainage point.

17. Install evaporative cooler in a domestic dwelling
Installation can be broken down into the following activities:
Install the dropper duct.
Flash the roof.
Mount the unit.
Install ducting in the roof space.
Install ceiling diffusers
Install water supply to the unit
Install Drainage provision for evaporative coolers
Electrical (by electrician)
Commission the evaporative cooler.
Cleanup.

18. Install the dropper duct
Select a location for the unit so that the flexible ductwork is of approximately equal length.
If possible situate it over the bathroom or laundry.
Remember there needs to be clearance for the duct connections on the bottom of the dropper. It is good if the dropper can be installed on the low side of the rafter under bearer.
Part of the roof needs to be removed to provide access.
This is a good opportunity to put the flexible ducting into the ceiling space while the roof is open.
The dropper duct needs to be mounted to the roof structure.

19. install the dropper duct
If a rafter has to be cut out then trimmers have to be installed to support the end of the cut rafter. Truss roof members must not be cut.
The dropper is boxed in and screwed to the timber structure.
Ensure that the dropper is plumb and square and not in contact with the ceiling timbers. If the dropper is not square then the unit may not fit.

20. Flashing the Tile roof Tile Installation
The two most common types of roof cladding are tiles and corrugated steel.
There are different types of flashing material available and may be used for both.
In this unit we will use lead to flash the tiles and steel flashing for the corrugated cladding.
Remember lead must not be used on tray deck roofing.
The tiles are cut around the ductwork so they are a close fit.
A piece of lead is cut so it is 150 mm wider than the duct on each side.
The lead is then shaped to fit the front of the duct to make an up stand at least 75mm high
Tile Installation

21. Flashing the Tile roof
Side flashings are then made with a 75mm up stand.
Remember that when doing flashing it is best to work from the bottom up.
Tile Installation

22. Flashing the tile roof Tile Installation
Make sure that where the flashing goes under the tiles that it is supported and the edge is turned forward 15mm to prevent leakage of water that may blow up under the tiles.
The rear flashing is then made from another piece of lead with a 75mm up stand.
Remember to leave a rain gutter between the tile ends and the back of the duct. 150mm Minimum

23. Flashing the tile roof Tile Installation
To complete the job lead is siliconed and screwed to the duct and finish beating the lead into the tiles.
Remember silicone must be in the joint between the lead and the duct.

24. Corrugated iron roof:
Cut a square hole in the corrugated roof sheet next to a rafter.
Cut the hole bigger to allow for the rain gutter behind the duct.
Rain gutter should be a minimum of 75mm wide.
Extend the cut at the top of the hole to the nearest corrugation crest that is at least 150mm away from the duct

25. Corrugated iron roof:
Make up the rear flashing and fit it into the cut at the top of the hole. Box the hole and screw the dropper to the timber making sure that it is plumb.
Finish your cuts both sides on the high rib

26. Corrugated iron roof:
Make up and fit the front flashing and rivet to the duct and the roof.
Remember flashing should be made of the same material as the roof.

27. Corrugated iron roof: Make up the side flashings.
Insert them under the back flashing and over the lower front flashing.
Mitre cut the lower end silicone and rivet to the duct and to the roof.

28. Mount the unit
Use the manufacturer’s instructions for mounting the unit.
You can take apart the unit to reduce the weight.
Remember to take care when lifting the unit in place.
Get someone to help you.

29. Moulded Flashings
An alternative method of flashing is shown in the picture.
These modern poly flashings are designed to be used on both tile and iron roofs.
They are useful as they reduce your installation time.
The base flashing is installed underneath the roofing material at the top end as usual and an angled adaptor is placed over the top and cut to suit the pitch of the roof then screwed on.
The plenum box simply clips over plastic lugs on the base flashing and adaptor plates the size of the ducting required once again simply snap on with no fasteners required.

30. Ducting installation
Ducting should be installed in straight lines to the diffusers.
Changes of direction should be at least 2 times duct diameter.
Use a long radius where ductwork is connected to diffusers.
Where ‘Y’ junctions are installed, ensure that the air from the incoming duct discharges equally to the branch ducts.
Flexible ductwork should be supported. Straps and hangars should not reduce the diameter of the duct. Maximum sag between supports should not be greater than 25mm.

31. Ducting installation Ducting must be insulated.
If the outer plastic covering on flexible ducting is damaged it must be repaired to ensure that the duct is airtight.
Duct tape is used to make joints where flexible ducting is used.
The inner core should be taped onto duct starters.
Insulation pulled onto the starter then the outer covering of the duct securely taped on.
Rigid ducting should be insulated and supported on hangers or other mounts.

32. Install the ceiling diffusers
Diffusers are mounted to the ceiling cladding, usually plaster.
Appropriate holes have to be cut in the ceiling. It will be necessary to locate the exact position of these holes so timber structure in the ceiling can be avoided.
If the diffuser is larger than the spacing between the ceiling joists then a ceiling joist will have to be cut out.
Any joist that has to be cut out should be supported on both sides of the cut.
This can be done by fixing timber across the top of the joists on each side of the penetration to support the joist that has to be cut.

33. Install the ceiling diffusers
Measure out the position of the diffuser making sure that it is square to the room.
Use a template to mark the perimeter of the hole to be cut. Use a keyhole saw to cut out the hole.
Remember to take care not to mark the ceiling where it can be seen.
Pull the flexible duct through the hole in the ceiling. Use duct tape to attach the diffuser flexible duct.
Fit off the diffuser.
You will have to read the fitting instructions for the diffuser that you are using. Install diffusers in the other rooms

34. Install water supply to the unit
Water has to be provided for the cooler unit.
If there is a hot water service in the ceiling space then a connection can be made for the cooler in the ceiling space.
If there is no water supply in the ceiling then connection will have to come from a tap or other point somewhere else.
A control valve is required for the unit. Where water is of poor quality a strainer may be installed.
Ensure that any penetrations that are seen that are made for piping are neat.
In areas subject to frost exposed piping must be lagged.
Use the water supply standard for sizing and support requirements.

35. Main Water proof Control Box
Controller Options
Remote Transponder
Plugs into the control box
Loom Wire
Manual over flow hole
Cold Water Inlet Float Valve
Automatic Dump valve
By pass tube to Solenoid Valve
Inlet Water Solenoid Valve
Loom wire plugs into Control Box & Bypass tube to Dump Valve

36. Connections to the unit
The manufactures installation guide will advise you on the correct procedure of connecting all components, electrical & water
Water Connection
A 15mm copper connection is supplied on most domestic evaporative coolers, an isolation valve is required on all appliances that have a water reservoir and a pump.
The solenoid valve is install next this electronically controlled valve will only open and allow water to enter the float valve once power has been obtained from the main control box.
The solenoid valve has an electrical connection & small water bypass tube which must be connected to the Dump valve.
Once charged with water this hose activates the Dump valve forcing it closed which allows the sump to fill.
The water pressure holds the Dump Valve closed until the unit is turned off, power is stopped to the solenoid valve by the control box .
No power to the solenoid stops the water flow to the bypass tube the Dump valve opens and the water is dumped to waste.

37. Connections to the unit
The main waterproof controller box which is inside the unit houses all the electronics to control the unit.
The loom that controls the solenoid valve (runs up to through the sump via the manual overflow pipe) needs to be plugged into the socket provided.
The 3 pin plug that supply's power to the unit is already connected to the control box and needs to be installed into the dropper duct via a 50mm hole that is provided in the unit sump adjacent to the control box.
The remote transponder or manual thermostat lead (depending on the unit) also need to pass through this same hole.
All these wires now are required to pass through a grommet provided in the duct winter seal.
A 50mm hole must be drilled into the dropper duct and a grommet installed by the installer . All the wires are now passed through the grommet into the ceiling space where the remote transponder is mounted and the power is plugged into a standard power point. If the unit has a manual thermostat the wire must be ran to a position nominated by the customer .

38. Install drainage provision for evaporative coolers
Water is pumped from a reservoir in the bottom of the evaporative unit, and via a distribution system, flows over the filter pads of the evaporative cooler an as the air is drawn into the unit the air is cooled via the wetted filter pads.
Most Evaporative coolers (apart from mobile units) will have a controlled automatic ‘bleed-off’ (or drain) to discharge small volumes of water.
Other evaporative units will incorporate a ‘Dump system’, where the full volume of water in the sump of the unit is discharged to waste periodically.
The replacement with fresh make-up water reduces the amount of salinity and suspended solids build up in the water reticulation system of the unit.

39. Install drainage provision for evaporative coolers
This make up water ensures the quality of the water is maintained by replenishing & replacing the water .
Drainage provision for evaporative coolers must be provided in accordance with the Plumbing Standards Regulations.
The discharge pipe from an evaporative cooler must be sized in accordance with the manufacturer’s requirements and specifications.
The drain from an evaporative cooler may discharge over a roof gutter downpipe connection.
This prevents unnecessary ponding in the gutter

40. Install drainage provision for evaporative coolers

41. Install drainage provision for evaporative coolers

42. Install drainage provision for evaporative coolers

43. Install drainage provision for evaporative coolers

44. Install drainage provision for evaporative coolers

45. Install drainage provision for evaporative coolers

46. Install drainage provision for evaporative coolers

47. Commission the evaporative cooler
Commissioning is a very important part of the installation and includes the following points:
Set the float level in the unit.
Check belts & pulleys are tight.
Check fan rotates freely (no scraping).
Check pump operation and connections.
Check water is going to all pads.
Set the water bleed.(if required}
Set diffuser blades (if adjustable).
Check airflow to registers.
Explain operation of unit to customer

48. Balancing
Balancing the system using an anemometer or balancing hood. An anemometer will measure the velocity of the air.
Quantities may be determined by the following formula:
Volume in litres = Velocity Metres per second x Area x 1000
If sizing has been done correctly then airflows should be near correct.
If the ducting layout is such that it does not favour any one outlet then balance should be good.

49. Operation of the unit Follow manufacturer’s instructions.
Turn the pump on first to wet the pads, then the main fan on.
Windows in the rooms that are to be cooled should be opened just enough to create a good flow of air.
Do not open doors fully as this will short circuit the airflow.
The pump may be turned off if humidity is high.
In winter time diffusers should be closed and the unit covered.
Some units come with their own covers or climate weather seals that automatically close when the unit is not in use.
Also some coolers have a timer to control times of operation

50. Maintenance of Evaporative Coolers
Correct maintenance of the evaporative cooler is important for the efficiency of cooling or ventilation.
Regular maintenance enables the cooler to perform to its designed efficiency. Regular maintenance helps prevent the premature breakdown of the operating components such as the filter pads, fan, water pump, water distribution system and controls.
If regular maintenance is not done on the evaporative cooler impurities can build up in the unit from induced dust, pollen, salt and minerals (due to water evaporation).

51. Maintenance of Evaporative Coolers
These impurities can block the pump, water distribution system or the filter pads.
Maintenance is also important to ensure good water quality used in the evaporative cooler, which in turn provides good air hygiene and cooling efficiency of the unit.
Regular cleaning and disinfection of the evaporative cooler prevents the build up of dissolved salts or residue on the filter pads, algae and sediment in the water sump of the unit and discourages bacteria growth in the unit.

52. Cleaning of the evaporative cooler
Cleaning and disinfection of an evaporative cooler needs to be done at least twice a year.
The regularity of cleaning may need to be increased depending on the location of the unit, the quality and type of water supply, (bore water, dam water, river or creek, mains supply or tank storage) and weather conditions.
Normally the evaporative cooler is cleaned before use (before summer) and after a period of use (after summer).
If the unit does not incorporate an automatic dump system then after a period of no use the water in the sump may become stagnant and foul. Then cleaning and disinfection is required.

53. The evaporative cooler should be cleaned in accordance with the manufactures recommendations .
Ensure unit is turned off
Remove the filter pads or frame assembly
Wash and hose down the filter pads or frame assembly and allow to drain. This should be done in a suitable location to allow the filter pads to drain properly.
Turn off water supply and drain the sump of water by removing the drain plug of the sump.
Clean the sump and surrounds and wash thoroughly including the water distribution system
Clean the sump of the evaporative cooler, all surrounds, including the water distribution system.
Replace the drain plug and turn the water supply on to fill the sump with fresh water. Add disinfectant as required and ensure that the sump fills to the required water level.
Replace filter pads or assembly frame

54. checking the components and operation of an evaporative cooler.
Ensure unit is turned off
Check flashings and surrounds of evaporative unit for soundness
Remove filter pads or frame assembly and check for wear and or damage. Replace filter pads or frame assembly if required.
If unit is an axial fan, check soundness of fan blades and bearings. If the fan is noisy when it is turned on it may be because of worn bearings or unbalanced fan blades. Repair or replaced any damaged components.
If unit has a centrifugal fan, check the drive belt for correct tension and pulleys wear. Check the bearings on the electrical motor and fan drum for wear and replace if necessary.

55. checking the components and operation of an evaporative cooler.
Check ‘O’ rings and seals for soundness.
Check water distribution system, bleed system if required, dumping system if required and pump for blockages and wear.
Check float vale assembly for correct water level and water valve for correct operation.
Check weather seal (if fitted) for operation.
Check all ducting components for soundness.
Replace filter pads or frame assembly and turn the unit on and check for correct operation and airflow according to the manufacturers specifications.
Cleanup
Pick up all surplus material and rubbish and remove from work site.
Check that all tools have been packed away.
Make sure that the owner has warranty cards and instruction books.

56. The end
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