Musty smell and startup odour
When the system smells stale on startup and you need to check deeper than the filter.
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When the system smells stale on startup and you need to check deeper than the filter.
When the customer can already see dark buildup beyond the front filter area.
When the system still runs but output and room comfort have dropped.
When service history is vague or the unit is clearly overdue for proper maintenance.
When local moisture and long run periods change the maintenance picture.
When the unit serves bedrooms, clinics, gyms, childcare, offices, or long-hour rooms.