Question 1

How do I size an air-conditioning system correctly for an office space?

Accepted Answer

Correct sizing starts with a proper cooling load calculation that accounts for floor area, heat generated by equipment and occupancy, insulation quality, glazing and orientation. An undersized system will run constantly without reaching set temperature, while an oversized system short cycles and wastes energy without improving comfort. This calculation should be done by the contractor before any unit or system type is recommended, not estimated from floor area alone.

Question 2

What's the cost difference between a split unit system and a centralised VRV or VRF system?

Accepted Answer

Split units typically cost less upfront and are simpler and faster to install, making them suitable for smaller or zoned spaces. Centralised VRV or VRF systems cost more initially but offer better efficiency, individual zone control and lower long-term running costs across larger buildings. The right choice depends on building size, layout and how independently different zones need to be controlled, not on upfront price alone.

Question 3

How often should commercial HVAC systems be serviced?

Accepted Answer

Commercial HVAC systems are commonly serviced on a quarterly basis, with filter checks carried out more frequently depending on usage, occupancy and how dusty the environment is. Higher-use spaces such as F&B outlets or server rooms usually need more frequent attention than a standard office. The schedule should be adjusted based on condition history rather than fixed permanently at installation.

Question 4

Why is water leaking from the air-conditioning unit even after the drain was cleared?

Accepted Answer

If leakage continues after a drain clearance, the cause is usually somewhere other than a simple blockage, such as insufficient fall in the drain pipe, a cracked condensate tray, damaged pipe insulation causing external condensation, or a vent and trap arrangement that is not working correctly. Repeatedly clearing the drain without checking these other points typically results in the leak returning. A proper inspection should identify which of these is the actual cause before further work is done.

Question 5

Can an air-conditioning system be diagnosed or serviced while the building stays occupied?

Accepted Answer

In most cases, yes, by scheduling work in zones and around operating hours so only the area being worked on is affected at any time. Diagnostic work such as measuring airflow, temperature and drainage can usually be done without shutting the system down completely. Full isolation or safety-critical testing may still require a short planned downtime for the specific zone involved.

Air-Conditioning

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Assess Your Cooling Load Properly.