Bukit Batok outdoor unit clicks: fan blade warped by afternoon heat
A Bukit Batok flat had an outdoor unit that developed a faint click on every fan rotation, worse specifically in the afternoon heat. This hillside estate gets strong, direct sun exposure on its west-facing ledges. A warped fan blade is easy to miss until the clicking actually becomes noticeable.
By Team Snowflake | Reviewed 11 Jul 2026
Case summary
Midea Wall-mounted10 years oldHDBBukit Batok, Singapore
- Concern
- The homeowner worried the fan motor itself was failing badly and would need a full, costly replacement soon.
- Found
- The fan blade had warped slightly from sustained afternoon heat, clipping the housing on each rotation
- Key check
- Checked the fan blade's shape against the housing before assuming a motor fault
- Result
- The clicking stopped completely, even through the hottest afternoons, after the new blade was fitted properly. The homeowner avoided paying for motor work that the unit never actually needed in the first place.
What we were told
The homeowner said the clicking was faint in the morning but grew clearly audible by mid-afternoon, then quietened again by evening. It still cooled normally throughout the day. The ledge faces west and gets direct sun for several hours each afternoon.
What we checked
We treated the time-of-day pattern as the first lead rather than opening the fan motor. A genuine motor fault tends to click fairly consistently regardless of temperature. Clicking that tracks the hottest hours of the day usually points at a part physically changing shape with heat instead.
The fan motor itself ran smoothly throughout, with no unusual internal noise when tested in isolation.
The fan blade had a slight warp along one edge, more pronounced than the rest of the blade.
That warped edge clipped the housing audibly only once the blade had warmed and expanded further.
No wear or damage was found anywhere on the motor bearings or housing itself at all.
What we found
Years of direct afternoon sun on this west-facing ledge had gradually warped one edge of the plastic fan blade. This likely came from repeated heat cycling day after day. In cooler morning conditions the warp sat just clear of the housing. Afternoon heat expanded the blade slightly further, enough for the warped edge to clip the housing on every rotation until temperatures dropped again in the evening.
What fixed it
We replaced the warped fan blade with a new one and confirmed clearance from the housing across a full range of outdoor temperatures. We did not recommend any motor work, since the motor itself tested cleanly throughout the visit. We advised a shade check for this ledge, since direct afternoon sun is the real driver of the warping.
Outcome
The clicking stopped completely, even through the hottest afternoons, after the new blade was fitted properly. The homeowner avoided paying for motor work that the unit never actually needed in the first place.
What this case teaches us
A click that worsens in the afternoon heat often means a warped blade, not the motor
- A click that specifically worsens in the hottest part of the day often points at a warped fan blade, not a failing motor.
- West-facing hillside ledges can push plastic fan blades to warp much faster than shaded installs.
- Ask for the fan blade's shape to be checked against the housing before approving fan motor replacement.
Related reading
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