SPECIFICATION – TECHNICAL
AIR-CONDITIONING UNITS – SINGLE AND SPLIT (DUCTED)
(AIR COOLED PACKAGED UNIT)
MAINTENANCE TYPE: STATUTORY
1.0 SCOPE OF SERVICES
The Contractor shall provide maintenance Services for the Air Cooled Packaged Units including associated ductwork covered by this Contract. The Services shall be carried out at the intervals stated below unless otherwise stated in the Equipment and Pricing Schedule.
2.0 MINIMUM STANDARD
The minimum standards for periodic inspection and servicing shall be as stated below and in accordance with the requirements of the current editions of:
• Fire and Rescue Service Act
• Building Act and Building Fire Safety Regulations • BCA Building Code of Australia
• QDC MP 6.1 Maintenance of Fire Safety Installations
• AS 1851 Maintenance of Fire Protection Systems and Equipment • AS/NZS 3788 Pressure equipment - In-service inspection • AS 3873 Pressure equipment - Operation and maintenance
• AS/NZS 3666.2 Air-handling and water systems of buildings – Microbial control Part 2: Operation and maintenance
• HB 40 The Australian Refrigeration and Air-conditioning Code of Good Practice 3.0 MINIMUM QUALIFICATIONS
The Contractor shall ensure that it has the appropriate licences issued by the Queensland Building Services Authority to perform the services under the Contract and must provide evidence to the satisfaction of the Principal.
The Contractor shall also ensure that persons who carry out required tests, services or make logbook entries are qualified in Refrigeration, Air Conditioning and Mechanical Services, with:
a) Expertise in the servicing and repair of packaged air conditioning units b) Accreditation in the handling of Ozone Depleting Substances
The Contractor shall hold valid licences issued under the Ozone Protection and Synthetic Greenhouse Gas Management Act 1989 as follows:
• National Refrigerant Trading Authorisation in the name of the company undertaking the work of the Contract.
• National Refrigerant Handling licence in the name of each employee of the company who is likely to handle refrigerants in undertaking the work of the Contract.
The above licences shall be produced upon request by the Principal's Representative.
4.0 REFRIGERANT MANAGEMENT
• All maintenance and work practices are to be in accordance with The Australian Refrigeration and Air-conditioning Code of Good Practice (HB 40).
• All refrigerant usage is to be recorded.
• Whilst undertaking servicing, maintenance and repairs to equipment of this Contract, service personnel shall take all necessary precautions to ensure that no refrigerant is released to the atmosphere.
• All refrigerant is to be recovered using an approved recovery unit.
• It is the responsibility of the Contractor to provide a suitable recovery unit for the installations of the Contract.
• All clean recovered refrigerant may be re-used. The Contractor shall ensure that the re-use of recovered refrigerant does not cause any system malfunction due to unacceptable contamination. • Recovered contaminated refrigerant shall not be re-used.
5.0 MAINTENANCE REQUIREMENTS AND FREQUENCY
Perform all the service requirements as detailed below: 5.1 Refrigeration Compressors It e m N o . Service Item Frequency T h re e -m o n th ly Y e a rl y
1 Measure suction and discharge pressures. 2 Check all safeties and pressure gauges.
3 Ensure the unloading mechanism and controls are functioning correctly. 4 Inspect and record oil level and pressure including crankcase heater condition. 5 Inspect compressor motor coupling and / or pulleys and belts where applicable. 6 Test for and repair refrigerant and oil leakage.
7 Check for undue noise and vibration.
8 Measure and record motor amperage. Compare with nameplate rating. 9 Change sequence switch and ensure correct operation.
10 Clean compressor, base and motor casing.
11 For open compressors take an oil sample from each compressor and analyse for acid, moisture, etc. If an oil change is required, liaise with the principal's representative regarding approval.
12 Check compressor motor terminals for hot connections, undertake resistance test of windings and record readings.
13 Check operation efficiency of suction discharge valves. 5.2 Air Cooled Condensers
It e m N o . Service Item Frequency T h re e -m o n th ly Y e a rl y
1 Check operation and condition of fans including fan cycling operation for head pressure modulating.
2 Check efficiency of condenser operation by reading compressor discharge pressure and report any abnormal function.
3 Clean condenser coils by hosing with water. 4 Report abnormal high noise level.
It e m N o . Service Item Frequency T h re e -m o n th ly Y e a rl y
5 Treat and paint corrosion as necessary.
6 Measure motor amperage and compare ratings.
7 Change lead-lag sequence on fan motors and calibrate head pressure modulating device.
8 Comb all condenser fins straight.
9 Supply and replace all belts on belt drive units.
10 Report on overall condition and indicate when replacement required. 5.3 Air Handling Unit and Air Filters
It e m N o . Service Item Frequency M o n th ly T h re e -m o n th ly S ix -m o n th ly Y e a rl y
1 Clean and flush condensate trays and drains. Ensure drain is running free. Leave tray dry.
2 Inspect cooling and heating (if fitted) coils:
• Comb fins straight and clean coils as required, using biodegradable, non-toxic, water-based odour-free foaming detergent.
• Provide MSDS prior to the first service or on request.
• Rinse coils thoroughly with clean water after applying detergents.
3 Check air filters (dry media):
• Check integrity of filter seals to ensure there is no air by-pass.
• Check that restraining brackets hold the filter frames securely and that the filter media is securely fastened.
• Repair filter handles and frames as required.
• Record pressure-drop across filters. If pressure-drop is excessive, report the circumstances to the principal’s representative for further instructions.
Note: supplying washable filter media and/or washing existing filter media are not acceptable.
• If removing dirty filter media from site, take care to avoid soiling floor coverings and other furnishings etc.
• Fans are to be turned off while filters are being inspected and/or changed. After completing the work, ensure the fans are turned on and operable.
• Remove filter debris from the chamber and leave clean and tidy.
It e m N o . Service Item Frequency M o n th ly T h re e -m o n th ly S ix -m o n th ly Y e a rl y
4 Check unit and seals for air leakage.
5 Check panels, doors and fastenings for security and air leaks. Repair any air leaks.
6 Check that insulation is clean and secure. Repair as required. 7 Check that all automatic volume control dampers and linkages are
fully operable. Lubricate, using a dry lubricant, as required. 8 Check that all automatic volume control dampers seal tight when
closed.
9 Check and record air on coil, air off coil, room, return air and outside air temperatures.
10 Check complete unit for corrosion or deterioration.
5.4 Fans and Motors – Supply or Return Air used in Day-To-Day Operation
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. Item Service Item
Frequency M o n th ly T h re e -m o n th ly Y e a rl y
1 Obstructions Check there are no physical obstructions likely to impede performance.
2 Noise,
overheating and vibration
Check motor and all bearings for noise, overheating and excessive vibration.
3 Flexible connections
Check flexible connections, where fitted, for leaks, tearing or fraying.
4 Fan belts (wear) Check fan belts for wear.
5 Guards and
other safety features
Check for satisfactory condition.
6 Bearings Check lubrication of bearings and lubricate as required.
7 Couplings Check couplings for tightness.
8 Fan belts (tension)
Check for correct tension.
9 Fan blades Clean fan blades and scrolls.
10 Pulley wheels and couplings
Check pulley wheels and couplings for alignment. 11 Casing guards
and impeller
Check casing, guards and impeller for corrosion. 12 Fan belts Supply and replace all drive belts.
5.5 Ductwork It e m N o . Service Item Frequency M o n th ly Y e a rl y
1 Check ductwork for air leakage. Repair minor leaks.
2 Check external insulation for retainment. Repair as required.
3 Check and clean all fresh air intakes, return air grilles, exhaust outlets and air relief transfer grilles.
4 Report severe deterioration of ductwork, insulation, dampers, heater banks and any build up of impurities.
5 Check integrity of flashing at external penetrations.
6 Check that all automatic terminal units are fully operable and that linkages are free to move.
7 Check that manual volume control dampers are correctly positioned and are freely adjustable.
8 Check and clean the following:
• Ductwork in the vicinity of moisture producing equipment.
• Drainage facilities associated with moisture producing equipment. • Air terminal units, including air registers.
• Steam and spray humidifiers, including line strainers, valves, sparge pipes, spray nozzles and other components discharging moisture into the airstream.
5.6 Air conditioning controls
It e m n o . Service item Frequency T h re e -m o n th ly S ix -m o n th ly
1 Check for burnt wiring. 2 Check all fuses.
3 Check all meters for correct operation. 4 Check all contactors for correct operation. 5 Ensure all relays are secure.
6 Test all run and fault lights. Supply and replace faulty switchboard/panel lights. 7 Ensure all cable duct covers are in place and secure.
8 Ensure all control covers are in place and secure. 9 Clean inside of switchboard/control panel.
10 Check operation of air compressor and drain vessel where applicable.
11 Check staging controls for correct operation. Report short cycling to Principal’s Representative.
It e m n o . Service item Frequency T h re e -m o n th ly S ix -m o n th ly
12 Check all temperatures and adjust if required.
13 Ensure all room thermostat covers are in place and secure.
14 Check set points of all controls for accuracy - recalibrate as required.
15 Ensure safety controls and devices are controlling at the recommended value. 16 Test all manual over-ride switches.
17 Test operation of all test switches. 5.7 System Shutdown (where applicable)
It e m N o .
Item Service Item
Frequency Y e a rl y
1 Full simulation Fully simulate a fire/smoke situation from any device such as a sprinkler, thermal or smoke detector, to effect shut-down of all air conditioning and mechanical ventilation systems not required to operate in fire mode (see clause 18.2.4 of AS 1851).
Check all systems required to shut down are not operating. 5.8 Pressure Vessels - Internal And External Inspection (where applicable)
The minimum standards for periodic inspection and servicing shall be as stated below and in accordance with the current requirements of AS\NZS 3788.
Inspections are required for vessels that contain either:
1) Group 1 refrigerants1 when the vessel has pV > 200MPa.L 2; or
2) Any refrigerant from Group A2, A3 and B2
It e m N o . Service Item Frequency 2 Y e a rl y 1 2 Y e a rl y 5.8.1 External Inspections
1 Inspect external surfaces of vessel for pitting.
2 Inspect external surfaces of vessel for cracks or splitting. 3 Inspect vessel for distortion or bulging.
4 Inspect vessel for corrosion. Repair as required.
1Refer AS/NZS 1677.1. Group A1 refrigerants include R22, R123, R 134a and R4xx blends. Group B2 includes R717 (Ammonia) and Groups A2 and A3 contain the flammable refrigerants – Propane , butane etc
It e m N o . Service Item Frequency 2 Y e a rl y 1 2 Y e a rl y
5 Remove all deposits and debris build-up from and around vessel. 6 Inspect condition of welds.
7 Inspect condition of all sockets, studs and flanges. 8 Inspect access panels for damage and sealing integrity. 9 Inspect vessel for leaks.
5.8.2 Internal Inspections
1 Inspect internal surfaces of vessel for pitting.
2 Inspect internal surfaces of vessel for cracks or splitting. 3 Inspect vessel for distortion or bulging.
4 Remove all deposits from vessel.
5 Inspect access panels for damage and sealing integrity. 6 Inspect vessel for leaks after reinstatement of access panels. 5.8.3 General
1 Supply a complete and concise report on each internal and external inspection. 2 Contact the Principal’s Representative if further work is required.
3 On completion of inspection the Contractor shall fix an aluminium tag (business card size) to the equipment. The tag shall indicate the contractor’s name, the Date Tested and the Next Test Date for both internal and external inspections.
