AC Ducting Setup

AHU Ducting & Terminal Connection Setup: AC Ducting Setup

In the 2026 Malaysian engineering landscape, the AC Ducting Setup for an AHU is the critical "highway" that determines both the energy efficiency and the acoustic comfort of a facility. Governed by MS 1525:2024 and the Energy Efficiency and Conservation Act (EECA) 2024, modern ducting must be engineered to minimize "System Effect" losses, ensuring the AHU meets its statutory Specific Fan Power (SFP) targets.

At EKG (Malaysia) SDN BHD, we design ducting systems to be Sterile, Silent, and Statutory-Compliant, bridging the gap between high-velocity airflow and quiet indoor environments.

1. The Statutory Framework: MS 1525 & SMACNA

Under the 2026 update to MS 1525, duct leakage and static pressure management are mandatory audit points for a building's Energy Management System (EnMS).

• Leakage Class: High-pressure main ducts must meet SMACNA Leakage Class 3 or better. Excessive leakage is now categorized as "Energy Waste" under EECA 2024, potentially leading to statutory penalties.

• Insulation Standards: To prevent "Sweating" in Malaysia's high-humidity climate, supply air ducts must be insulated with a minimum of 25mm to 50mm of closed-cell elastomeric foam or fiberglass with a reinforced foil vapor barrier, maintaining a minimum R-value of 6.0.

• GITA Support: High-efficiency ducting setups that utilize low-friction fittings and high-performance insulation are eligible for the 100% Green Investment Tax Allowance.

2. Core Components of the AHU Connection

The connection between the AHU and the main ductwork is where most aerodynamic and acoustic issues originate.

3. Aerodynamic Optimization & SFP

To satisfy the EECA 2024 mandate of keeping SFP below 1.6 kW/m³/s, the ducting setup must prioritize smooth transitions:

1. Aspect Ratio: We maintain a preferred duct aspect ratio of 1:1 to 3:1. Excessive "flat" ducts (e.g., 8:1) significantly increase friction and fan energy waste.

2. Turning Vanes: Every 90° elbow in the main supply line is fitted with aerofoil turning vanes to prevent "Air Hammer" and pressure drops.

3. Static Regain Design: For long horizontal runs, we utilize static regain calculations to ensure that terminal VAV boxes receive consistent pressure regardless of their distance from the AHU.

4. The "Fire Mode" Statutory Protocol

The ducting setup is the primary path for smoke travel during an emergency. Under BOMBA (JBPM) 2026 regulations, specific "Terminal Connections" are mandatory:

• Motorized Fire Dampers (MFD): Every duct penetrating a fire-rated wall or floor slab must have an MFD hard-wired to the Fire Alarm Monitoring System (FAMS).

• Automatic Fire Signal AHU Shut-off: Upon MFD closure, the AHU VFD must receive an immediate signal to stop, preventing duct over-pressurization and potential bursting.

• BOMBA Witness Test: JBPM officers will witness the "Drop-Test" of fire dampers and the corresponding AHU shutdown during the annual Fire Certificate (FC) audit.

5. Why Partner with EKG (Malaysia) SDN BHD?

• Technical Integrity: Our ducting designs are led by mechanical specialists who perform complex Static Pressure Calculations to ensure your VFD isn't "fighting" poorly designed elbows.

• Acoustic Excellence: We specialize in internal acoustic lagging for sensitive environments like boardrooms and recording studios, ensuring zero "duct rumble."

• EECA Compliance Support: We provide the "Duct Leakage Test Report" and insulation verification required by your Registered Energy Auditor (REA) for mandatory submissions.

Is your ducting setup a source of noise and energy waste? Contact EKG (Malaysia) SDN BHD today for a specialized Ducting & Static Pressure Audit.