Factory office warm again: condenser fan blade cracked by years of grit

Daikin Cassette·11 years old·Industrial·Pioneer, Singapore

The factory office had become warm again despite regular servicing. The team wanted to know whether the compressor was failing.

We inspected the outdoor unit because the indoor side had already been serviced and the office sat near workshop air. The coil face looked only lightly fouled, which did not match how weak the airflow felt at the discharge side. That mismatch pointed at the fan itself rather than surface buildup, so we checked the blade's condition and how much air it was actually moving.

The condenser fan blade had cracked and warped after years running in oil-laden factory air. Fine grit had worked into the plastic and worn it from the inside, until the blade lost its shape and could no longer push a full volume of air across the coil. The coil face was only lightly fouled, not the thick blanket seen at dustier sites, so cleaning alone would not have fixed this. With less air moving through, the coil could not release heat properly, so the compressor ran harder to compensate. That is why the office warmed up again soon after a normal service: the fault was mechanical, not dirt.

We recommended replacing the fan blade rather than another condenser wash, since the coil did not need it. Compressor replacement was not justified by the checks. We fitted a new blade and confirmed it moved a full, even volume of air across the coil before closing the unit. We also told the office to check the fan blade's condition, not just the coil face, when warmth returns quickly in a site with heavy airborne grit.