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Defects
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Probable causes for the defect
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Design for Maintainability (DfM) Guidelines
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| Insensitive thermostat |
- Wrong location doesn’t allow it to sense the room temperature.
- Sensors are not recalibrated at regular interval. May be due to poor accessibility or poor maintenance practises.
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Design
Construction
Maintenance
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Fungal growth / stains on walls or ceiling
 Mould growth on ceiling |
- Moisture entry from fresh air inlet.
- Infiltration of external warm air – short circuiting.
- Moisture carry over from cooling coil.
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Design
Construction
Maintenance
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Excessive noise from machinery spaces
AHU near occupant space
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- Location of AHU plant room within occupancy space.
- Poor acoustical insulation of the mechanical room.
- The installation on isolator is not levelled.
- Worn out isolator or lack of lubrication of AHU, FCU or chiller plant equipment.
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Design
Construction
Maintenance
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| User dissatisfied, sick (SBS) |
- Air from cooling tower gets sucked by air intakes. It may cause legionella infection.
- Mould growth in return air plenum. Using ducts, grilles and regular cleaning can prevent such problem.
- Dumping of cold air or malfunction of VAV terminal / FCU (often poor access for maintenance).
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Design
Construction
Maintenance
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References
[1]
Normative References/Standards Referred to for Indoor Environment