How often should commercial air conditioning be serviced?

The honest answer is that it depends on duty, environment and consequence of failure. The unhelpful answer, the one printed in most manuals, is annually. In Far North Queensland, an annual service on a hard-working commercial system is not maintenance, it is a post-mortem.

A practical schedule for FNQ commercial sites

• ·Quarterly: retail, hospitality, medical, coastal sites, kitchens, and anything running seven days
• ·Six-monthly: low-occupancy offices, inland sites with light duty, single-tenancy buildings
• ·Monthly to quarterly: cool rooms, freezer rooms and process refrigeration where stock is at risk
• ·Pre-wet-season: drainage, tray and roof-penetration checks on every site, regardless of frequency

Why the tropics change the maths

Three local factors accelerate wear. Humidity keeps latent load high, so compressors run longer hours than the same equipment further south. Coastal salt air attacks coils and cabinets, reducing heat transfer and eventually causing leaks. And the wet season loads condensate systems heavily, a partially blocked drain that would be harmless in Melbourne will put water through a ceiling here.

Add dust from dry-season conditions inland and grease loading in kitchens, and coil fouling becomes the single most common cause of capacity loss we find on site.

What a proper service includes

• ·Condenser and evaporator coil cleaning, not just a visual check
• ·Filter replacement and drain clearing with a flow test
• ·Refrigerant pressures, superheat and subcooling recorded
• ·Electrical testing: contactors, capacitors, amp draw against nameplate
• ·Belt, bearing and fan condition assessment
• ·Controls and thermostat verification
• ·A written report with photos and recommended works

The commercial case

A quarterly service costs a known amount. An emergency compressor failure on a Saturday costs the call-out, the parts, the downtime and sometimes the stock. Across the portfolios we maintain, planned servicing consistently reduces total annual mechanical spend, not because the servicing is cheap, but because the failures stop.