Service Technician, VRF

DMG SC INC; Orange (CA); On-site; USD 75,000 - 95,000; Full time

Job summary

DMG SC INC is seeking a skilled HVAC Service Technician to support installation, start-up, commissioning, troubleshooting, maintenance, and repair of commercial HVAC equipment, focusing on AAON and LG systems. The role involves working directly with customers, management, controls personnel, contractors, and manufacturers to diagnose and resolve mechanical and controls-related issues.

The ideal candidate has strong commercial HVAC experience, excellent troubleshooting skills, and the ability to

Qualifications

• 3+ years of commercial HVAC service experience preferred.
• Ability to read electrical schematics and wiring diagrams.
• Strong mechanical and electrical troubleshooting skills.
• Knowledge of refrigeration fundamentals.
• Ability to use HVAC diagnostic instruments.

Responsibilities

• Diagnose and repair commercial HVAC equipment including AAON rooftop units, AAON air-handling equipment, LG VRF systems, and related components.
• Perform factory start-up and commissioning of AAON and LG equipment with proper documentation.
• Conduct scheduled preventive maintenance on various HVAC systems and document findings.
• Communicate clearly with customers, facility managers, and contractors, and provide repair recommendations.
• Complete accurate field service reports with equipment data, readings, and part numbers.

Skills

HVAC service

Troubleshooting

Electrical schematics

DX refrigeration

Customer service

System commissioning

Diagnostics instruments

Job description

About Us

We are a recognized industry leader in providing custom HVAC products and services for the commercial, industrial, healthcare/life sciences and residential building markets. We offer product expertise, technical and application support, system design and operational support thereby meeting our clients’ specific needs and requirements. As part of the Ambient Enterprises family of brands, the DMG team consists of experienced industry-leading professionals, focused on logistical, energy and cost-effective solutions to our clients.

Job Description

The AAON & LG HVAC Service Technician is responsible for the installation, support, start-up, commissioning, troubleshooting, maintenance, and repair of commercial HVAC equipment, with a primary focus on AAON and LG equipment. The technician will work directly with customers, service management, controls personnel, contractors, and manufacturers to diagnose and resolve mechanical and controls-related issues. The ideal candidate will have strong commercial HVAC experience, excellent troubleshooting skills, and the ability to work independently while maintaining a high level of customer service and professionalism.

Key Responsibilities

Service & Troubleshooting

Diagnose and repair commercial HVAC equipment, including:

• AAON packaged rooftop units
• AAON air-handling equipment
• LG VRF systems
• LG heat-pump and heat-recovery systems
• DX and refrigeration systems
• Hydronic heating and cooling systems
• VFDs, motors, compressors, fans, and associated components

Troubleshoot electrical, mechanical, refrigeration, and controls issues. Identify root causes rather than simply correcting symptoms. Perform system testing and verify proper operation after repairs.

Start-Up & Commissioning

Perform factory start-up and commissioning of AAON and LG equipment. Verify refrigerant charge, airflow, temperatures, pressures, electrical characteristics, safeties, and operating sequences. Complete manufacturer start-up documentation. Coordinate with controls technicians during BMS integration and functional testing. Assist with commissioning and troubleshooting of equipment connected to building automation systems.

Preventive Maintenance

Perform scheduled preventive maintenance on commercial HVAC equipment. Inspect coils, filters, belts, bearings, motors, compressors, electrical components, dampers, economizers, and refrigeration systems. Identify developing equipment problems and recommend corrective action. Provide customers with repair recommendations and equipment condition reports.

Customer Service

Communicate professionally with customers, facility managers, contractors, and other trades. Explain equipment problems and recommended repairs in a clear, understandable manner. Maintain a professional appearance and attitude while representing DMG. Respond to emergency and after-hours service calls as required.

Documentation

Complete accurate field service reports for every service visit. Document equipment condition, troubleshooting performed, readings, repairs, and recommendations. Include photographs, equipment information, and part numbers when appropriate. Maintain accurate labor, travel, and material records. Identify potential repair and replacement opportunities for the Service & Controls sales team.

Required Qualifications

• 3+ years of commercial HVAC service experience preferred.
• Strong knowledge of commercial HVAC systems.
• Ability to read electrical schematics and wiring diagrams.
• Strong mechanical and electrical troubleshooting skills.
• Knowledge of refrigeration fundamentals.
• Ability to use electrical and HVAC diagnostic instruments.
• Valid driver's license and acceptable driving record.
• Ability to work independently and manage multiple service calls.
• Strong written and verbal communication skills.
• Ability to work safely in commercial and industrial environments.

Preferred Qualifications

• Experience servicing AAON equipment.
• Experience servicing LG VRF systems.
• AAON factory training or certification.
• LG VRF training or certification.
• Experience with equipment start-up and commissioning.

Physical Requirements

• Ability to lift and carry HVAC tools and components.
• Ability to climb ladders and access rooftops.
• Ability to work in confined spaces and mechanical rooms.
• Ability to work outdoors in varying weather conditions.

Ambient Enterprises provides equal employment opportunities to all employees and applicants for employment and prohibits discrimination and harassment of any type without regard to race, color, religion, age, sex, national origin, disability status, genetics, protected veteran status, sexual orientation, gender identity or expression, or any other characteristic protected by federal, state or local laws.

Ambient is a national collective of HVAC firms. Our experts deliver safety, comfort, and highly efficient, sustainable solutions for spaces that matter most: healthcare, commercial, institutional, and mission-critical.