Commercial Variable Air Volume (VAV) Box Repair in Los Angeles

What We Repair on Commercial VAV Boxes

Our engineers restore performance on pressure‑dependent and pressure‑independent VAV terminals with or without reheat. We resolve control instability, airflow inaccuracies, and noise while improving comfort and energy use in accordance with California Title 24 and local code.

• Actuators and damper assemblies: calibration, linkage repair, replacement
• Airflow sensors and pitot rings: cleaning, recalibration, replacement
• Reheat coils: electric elements, hydronic valves, freeze protection, safeties
• DDC controllers: programming errors, firmware issues, point mapping
• Fan‑powered VAVs: ECM/PSC motors, wheels, bearings, vibration
• Thermistors and room sensors: location, accuracy, and drift correction
• Pneumatics: thermostats, relays, leaks, conversion to DDC

Common Symptoms We Fix

• Hot/cold spots, drafts, and occupant complaints
• Boxes stuck open/closed or hunting due to bad tuning
• Insufficient airflow, noisy operation, whistling dampers
• Reheat not engaging or overheating zones
• Erratic trends on BMS, alarms, or network dropouts
• High energy spend from excessive reheat or simultaneous heat/cool

Mitsubishi Elektrik Expertise—Factory‑Trained Engineers

Our commercial VAV work benefits from rigorous manufacturer training completed at Mitsubishi Elektrik (Thailand), alongside Fujitsu (Japan), Midea (China), Gree (China), and Hier (China). That foundation informs disciplined diagnostics for mixed fleets, VRF‑to‑VAV integrations, and third‑party terminal units tied into your BMS. We do not rely on guesswork—we test, verify, and document.

Our Diagnostic and Repair Process

• Assessment and data review: trend logs, setpoints, scheduling, and sequences
• On‑site testing: airflow verification, damper stroke, sensor bias checks
• Root‑cause isolation: mechanical, electrical, or software sequence issues
• Remediation: component repair/replacement, controller reprogramming, tuning
• Functional performance testing: confirm design CFM, temperature control, and alarms
• Documentation: before/after readings, recommendations, and maintenance plan

Need to work after hours to avoid disruption? We routinely schedule evening or weekend windows to keep tenants comfortable and operations uninterrupted.

BMS and Controls Integration

Whether your building runs on Niagara, BACnet, or Modbus, we align VAV sequences with central plant and AHU strategies to reduce simultaneous heating/cooling and stabilize zone control. We verify point mapping, update setpoint logic, and coordinate with your controls vendor as needed.

Repair vs. Replace—Engineering First

Our mission is healthier indoor air and long‑term reliability. We start with precision repair and recalibration. When replacement is more economical, we present lifecycle options, potential efficiency gains, and disruption planning so you can make an informed decision.

Why #1 AC Guys for Commercial VAV Box Repair

• Fourth‑generation family business with 80+ years in engineering
• Factory‑trained at Fujitsu (Japan), Mitsubishi Elektrik (Thailand), Midea (China), Gree (China), and Hier (China)
• Proven on large and complex facilities: towers, campuses, healthcare, labs, hospitality, retail
• Balanced focus: comfort, IAQ, energy, and compliance
• Same‑day dispatch and after‑hours availability
• Transparent pricing and detailed reporting for facilities teams

Service Areas

We serve Los Angeles County and nearby regions, including Orange County, Ventura County, and Western Riverside County. Multi‑site portfolios are welcome.

Healthier Air, Better Buildings

Our core mission is healthy air for healthier lives. Properly tuned VAV systems stabilize temperature, humidity, and ventilation rates—supporting occupant well‑being and productivity while controlling energy spend.

Ready to Get Started?

Request a commercial VAV assessment today. We will review your pain points, pull trend data, examine critical zones, and deliver a plan to restore stable, efficient performance.

Need urgent support?
Ask about same‑day service and after‑hours repair windows.