Quality is everyone's responsibility. |
Air-Conditioning Servicing. Do it right, do it well.Why do we service our AC units?
- because it is not working - because we want clean air - because it is a contractual obligation to do so Regardless of intents (other than the last one), we will want a clean and working AC unit after each service. After all, we are breathing in the air that it recycles. Airconreviewed produced this comprehensive list of steps for general routine service for two reasons. We want users to understand and appreciate good services, and hopefully, we can all have a good standard of service. |
General & Routine Service
Recommended Steps
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1. Pre-Service Checks
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1. Pre-Service Checks
Check controller for error codes.
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The Average Contractor: ✓ Airconreviewed Recommends: ✓
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Check FCU return and off-coil temperature with a thermometer.
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The Average Contractor: X Airconreviewed Recommends: ✓
~ To determine optimal operating temperature, contractors usually use their experience and hands to feel. Accuracies are questionable.
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Check the air-flow with an air-flow meter.
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The Average Contractor: X Airconreviewed Recommends: ✓
~ To determine before-and-after service air-flow performance.
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1. Check full-load refrigerant operating pressures with manifold gauges.
2. Check full-load operating current with a multimeter. |
The Average Contractor: X Airconreviewed Recommends: ✓
~ Obtaining operating parameters are basic engineering practises, and these figures can show if the equipment is operating normally.
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Visual checks on conditions of condenser brackets (if applicable), refrigerant pipes, power and connecting cables, insulations, signs of condensations or any other abnormalities.
Suggest recommendations, if necessary. |
The Average Contractor: X Airconreviewed Recommends: ✓
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2. FCU (Indoor Unit) Service
Clean FCU cover.
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The Average Contractor: ✓
Airconreviewed Recommends: ✓
~ Cleaning must be as detailed as possible, and any traces of moulds or dirts should be removed. Why else would you want to clean it?
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Clean filters.
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The Average Contractor: ✓ Airconreviewed Recommends: ✓
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Clean drain pan.
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The Average Contractor: ✓
Airconreviewed Recommends: ✓
~ Cleaning must be as detailed as possible, and any traces of moulds or dirts should be removed. Why else would you want to clean it?
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1. Vacuum drainage pipe.
2. Air purge drainage pipe. |
The Average Contractor: ✓ Airconreviewed Recommends: ✓
~ Pipe vacuuming, coupled with pipe purging, will be more effective in removal of grime. Most contractors do not do pipe purging.
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Vacuum evaporator coil.
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The Average Contractor: ✓ Airconreviewed Recommends: ✓
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Flush evaporator coil.
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The Average Contractor: X Airconreviewed Recommends: ✓
~ Few contractors flush the evaporator coil. Vacuuming alone cannot remove the deep-seated dirts.
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Brush fan blower.
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The Average Contractor: ✓
Airconreviewed Recommends: X
~ Brushing cannot clean the blower wheel thoroughly. It can only remove dirts on the surface.
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Dismantle and flush fan blower.
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The Average Contractor: X
Airconreviewed Recommends: ✓
~ The only way to clean a fan blower wheel thoroughly. Moreover, dirts and moulds hidden behind the blower wheel can be reached once it is removed.
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1. Check electrical terminals and printed circuit boards.
2. Tighten all electrical terminals. 3. Remove dust. 4. Check fan motor conditions. |
The Average Contractor: X Airconreviewed Recommends: ✓
~ Loose cables are fire hazards. Dust on the printed circuit boards can damage the boards.
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3. Condenser (Outdoor Unit) Service
1. Vacuum condenser coil.
2. Flush condenser coil. |
The Average Contractor: X Airconreviewed Recommends: ✓
~ Condenser coil must be cleaned and maintained to ensure optimal heat exchanges. A dirty coil will affect cooling, and can damage the compressor.
However, flushing of the condenser coil can be tricky in HDBs, condominiums or office towers. Seek advice from service technicians. |
Check and clean condenser fan blade and fan motor.
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The Average Contractor: X Airconreviewed Recommends: ✓
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1. Check electrical terminals, printed circuit boards, compressor and all electrical components.
2. Tighten all electrical terminals. 3. Remove dust. |
The Average Contractor: X Airconreviewed Recommends: ✓
~ Loose cables are fire hazards. Dust on the printed circuit boards can damage the boards.
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Clean condenser casing.
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The Average Contractor: X Airconreviewed Recommends: ✓
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1. Check condenser mountings, brackets, bolts and nuts.
2. Paint all rusty parts. |
The Average Contractor: X Airconreviewed Recommends: ✓
~ Condensers are often installed outdoors at height. It is important to ensure all mounting structures are sound and secured.
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4. Testing, Commissioning & Reporting
1. Record full-load refrigerant operating pressures.
2. Record full-load operating current. |
The Average Contractor: X Airconreviewed Recommends: ✓
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Record FCU off-coil temperature.
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The Average Contractor: X Airconreviewed Recommends: ✓
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Record air flow.
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The Average Contractor: X Airconreviewed Recommends: ✓
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Reporting:
1. Findings 2. Recommendations 3. Before-and-after technical datas 4. Conclusions 5. Photos |
The Average Contractor: X Airconreviewed Recommends: ✓
~ Reports are used to document before-and-after events. Documented details provide a source of reference for the next service or troubleshooting.
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Housekeeping
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The Average Contractor: ✓ Airconreviewed Recommends: ✓
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Our comprehensive list of steps to service an AC system will require additional effort, patience and time. We expect cost of service to be higher, but also a much cleaner unit nonetheless.
Notes:
1. There are a few brands and models of AC units that cannot be taken apart to such extent to be cleaned. These units will need to be taken down to be serviced.
2. This is not a scope for chemical cleaning.
3. This list is not exhaustive, and we may make changes when necessary.
4. This scope of work is drafted and recommended by airconreviewed.
airconreviewed. 30 November 2017
Rev(1) 07 April 2018
1. There are a few brands and models of AC units that cannot be taken apart to such extent to be cleaned. These units will need to be taken down to be serviced.
2. This is not a scope for chemical cleaning.
3. This list is not exhaustive, and we may make changes when necessary.
4. This scope of work is drafted and recommended by airconreviewed.
airconreviewed. 30 November 2017
Rev(1) 07 April 2018