Facilities HVAC Technician

Why Castelion, Why Now

Castelion is moving incredibly fast to develop and deliver advanced defense systems at a time when execution matters more than ever. We believe focus, ownership, and excellence are decisive advantages - and we're building a world-class team to turn bold ideas into real capability.

This is a rare opportunity to join at an early stage, where you'll have significant ownership, collaborate with exceptional teammates, and make a direct, measurable impact on our mission and the future of the company - regardless of your function.

Facilities HVAC Technician

Key responsibilities

• Perform repairs and maintenance on HVAC and process cooling equipment — AHUs, chillers, cooling towers, VAVs, Heaters, Boilers, Air compressors, Air Dryers, Freezers.
• Conduct routine and periodic inspections to identify necessary repair and maintenance work before breakdowns occur
• Use hand and power tools to troubleshoot, test, inspect, and repair mechanical and refrigeration equipment
• Review and follow blueprints, sketches, wiring diagrams, and equipment specifications
• Install, service, modify, rebuild, repair, and perform preventive maintenance on HVAC and refrigeration systems in accordance with applicable building codes and safety regulations
• Document and maintain records for the Maintenance Department, including preventive maintenance activities and service reports.
• Be physically capable of working from ladders and in high places, lifting over 50 lbs., and following exacting written and verbal instructions
• Capable of installing duct work, BACnet/JACE controls, and replacing packaged units.
• Assist in managing site-wide operations and support tasks as assigned
• Work on an on‑call basis and handle responsibilities assigned by management.

Basic Qualifications

• High School Diploma or equivalent, with 4 years of experience in HVAC, chillers, cooling towers, plumbing, and mechanical systems.
• Must own Basic HVAC Tools.
• Must possess a Universal EPA certification and an Active California Driver’s License.
• Familiarity with electrical/electronic components related to air conditioning and refrigeration equipment.

Preferred Qualifications

• Written and Verbal Communication Skills.
• Strong commercial HVAC and refrigeration experience.
• Experience in Aerospace/Defense Industry.
• Strong computer, math, analytical, and planning skills.
• Experience with building maintenance management and work order tracking systems
• Knowledge of building automation control systems and troubleshooting I/O.
• Experience with Microsoft Outlook.
• Experience working on HVAC equipment in a manufacturing environment that serves production machines.

Castelion offers a generous benefits package. Please refer to the bottom of our Careers page for more details.

Other Duties

Please note this job description is not designed to cover or contain a comprehensive listing of activities, duties or responsibilities that are required of the employee for this job. Duties, responsibilities and activities may change at any time with or without notice.

Additional Eligibility Requirements

This position may require access to classified information or restricted U.S. Government sites, systems, or information, as determined by the Company and/or applicable U.S. Government requirements. If the position is so designated, your employment in the role may be contingent upon your ability to obtain and maintain the required U.S. Government security clearance or other government authorization, and to satisfy any citizenship or other eligibility requirements imposed by applicable law, regulation, executive order, or government contract requirements. You will be notified if and when such requirements apply.

Affirmative Action/EEO Statement

Castelion is an Equal Opportunity Employer. We are committed to providing equal employment opportunities to all applicants and employees without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability, genetic information, protected veteran status, or any other characteristic protected by applicable federal, state, or local law.

Castelion is committed to providing reasonable accommodations to qualified individuals with disabilities throughout the application and hiring process. If you require a reasonable accommodation to complete an application, participate in the interview process, or otherwise participate in the hiring process, please contact View email address on aiapply.co. Requests for accommodation will be considered on an individual basis and handled in accordance with applicable law.

Castelion is committed to fostering a workplace where employment decisions are based on qualifications, business needs, and the ability to perform the essential functions of the role, with or without reasonable accommodation.

EAR/ITAR Requirements

This position requires access to export-controlled information, and as such, employment (or hiring of a contractor) is contingent upon the candidate’s ability to access all applicable export-controlled information without additional export licensing being required by the Bureau of Industry and Security and/or the Directorate of Defense Trade Controls.