Carrier Air Handling Unit (AHU)

An air handler contains the fan, filters, coils and dampers that condition and move air through a building's duct system. It may be a large built-up plant unit or a compact cabinet serving one floor.

Service interval: Annual coil and pan service; filters quarterly or tighter Commercial HVAC

How this equipment fouls

Everything the building breathes passes through the AHU. Filter bypass — air leaking around badly seated filters — is the usual reason coils foul even when filters are being changed on schedule.

Common failures

Coil faces fouled through filter bypass around poorly seated filter banks
Drain pan holding standing water and growing biofilm
Fan belts worn or misaligned where belt drive is used
Dampers and actuators seized, so outdoor-air ratio is wrong
Access doors leaking, reducing delivered airflow across the building

Maintenance that prevents them

Inspect and reseat filter banks, not just replace the media
Clean coil faces and confirm the pan drains completely
Check belt condition and alignment where fitted
Verify access panel seals after any service visit

Operating in Montreal & Quebec

Buildings sealed tight against Montreal winters depend on the AHU for all fresh air, so coil and pan hygiene has a direct effect on indoor air complaints between December and March. Outdoor-air dampers that seize part-open through a freeze-thaw cycle also drive heating costs up without any obvious symptom other than a cold zone. Checking damper travel at the same visit as coil cleaning catches a fault that would otherwise stay invisible until the heating bill arrives.

What Climeo does on this equipment. Climeo cleans accessible coil faces, drain pans and blower assemblies where they can be reached without dismantling that requires licensed work. Damper, actuator and control faults are referred out.

About Carrier

One of the largest global HVAC manufacturers, with a broad commercial range spanning rooftop units, applied air handling, VRF and ductless equipment.

Climeo is an independent cleaning specialist and is not affiliated with, endorsed by, or an authorised dealer for Carrier. Equipment names are used only to describe the equipment serviced.

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