Precision Power for Every Climate System

Heating, ventilation and air-conditioning equipment is among the most electrically demanding plant in any building. A ducted reverse-cycle system serving a large residential home can draw 20–30 A on startup alone; a commercial centrifugal chiller can demand hundreds of amperes across three phases. When that supply is under-engineered, the consequences range from nuisance circuit-breaker trips to catastrophic motor failure. StarWatt Systems designs HVAC electrical infrastructure from first principles, ensuring every conductor, switchgear component and protective device is sized for the actual load — not a rough estimate.

Our licensed electricians work directly with HVAC engineers and mechanical contractors to coordinate rough-in timing, confirm equipment specifications before materials are ordered, and deliver a finished installation that the commissioning technician can energise with confidence.

Dedicated Circuits and Sub-Board Design

Every air-conditioning unit — split system, ducted, multi-head or VRF — deserves its own dedicated circuit, correctly rated for the compressor's locked-rotor current and equipped with appropriately sized motor protection. Sharing circuits between HVAC equipment and general-purpose loads introduces voltage-drop issues and creates interference that shortens compressor life. StarWatt designs standalone sub-boards for HVAC plant, incorporating correctly rated MCBs, RCDs, isolators and surge-protection devices so each unit operates within its electrical design envelope.

• Load calculations using manufacturer data sheets, not rule-of-thumb estimates
• Dedicated circuits for each outdoor compressor and indoor air handler
• Correct conductor sizing to limit voltage drop to under 5% at full load
• Lockable isolators and safety-rated disconnect switches at each unit
• Surge-protection devices to guard inverter-driven compressors
• Sub-board labelling compliant with AS/NZS 3000 wiring rules

Three-Phase Supply for Commercial and Industrial HVAC

Rooftop packaged units, large-capacity split systems and precision air-conditioning equipment for data centres and manufacturing environments routinely require three-phase 415 V supplies. StarWatt's commercial electricians are experienced with three-phase motor starters, soft-starters and variable-speed drives used in modern HVAC plant. We install and terminate power cabling for chillers, cooling towers, air-handling units and heat-recovery ventilators, verifying phase rotation before energisation to prevent costly motor damage.

Thermostat and BMS Integration

Modern HVAC systems increasingly communicate across building management system networks — BACnet, Modbus and LON are common protocols in commercial buildings. StarWatt provides the low-voltage control wiring and data pathways these systems require, running shielded twisted-pair cables with correct termination impedances to prevent signal degradation. Our electricians install and connect room temperature sensors, zone controllers, motorised dampers, VAV boxes and central BMS panels, working from the mechanical consultant's control diagrams to ensure the control logic is implemented exactly as engineered.

• Control wiring for room thermostats, zone controllers and programmable time clocks
• BMS data cabling in BACnet/IP, Modbus RTU and LON formats
• Motorised damper and VAV box wiring and commissioning support
• Power supply for fresh-air heat-recovery ventilator control boards
• Integration with building automation front-ends and SCADA systems

Switchboard Upgrades for HVAC Retrofits

Retrofitting new air-conditioning into an older commercial building almost always exposes switchboard limitations — undersized mains, full bus bars, or protective devices that predate modern standards. StarWatt conducts a full switchboard audit before any HVAC electrical work begins, identifying capacity constraints and presenting upgrade options that meet AS/NZS 3000 while minimising disruption to occupied tenancies. Where partial energisation is required during upgrade works, we develop safe switching procedures to maintain cooling to critical areas.

Compliance, Testing and Handover

Every StarWatt HVAC electrical installation is tested and inspected to the requirements of AS/NZS 3000, with insulation resistance, earth continuity and RCD trip-time results recorded in a formal test report. We provide a Certificate of Compliance for Electrical Work (CCEW) or the equivalent state-specific compliance certificate with every installation, giving building owners, tenants and insurers documented assurance that the work meets the required standard. Commissioning checklists are completed in collaboration with the HVAC contractor so the full system handover is clean and traceable.