Senior HVAC Mechanic - Washington, DC

M.C. Dean is Building Intelligence®. We design, build, operate, and maintain cyber-physical solutions for the nation’s most recognizable mission critical facilities, secure environments, complex infrastructure, and global enterprises. The company’s capabilities include electrical, electronic security, telecommunications, life safety, automation and controls, audio visual, and IT systems. M.C. Dean is headquartered in Tysons, Virginia, and employs more than 7,000 professionals who engineer and deploy automated, secure, and resilient power and technology systems; and deliver the management platforms essential for long-term system sustainability.

Why join M.C. Dean? Our people are inspired by the way engineering and innovation enhance customer outcomes, improve lives, and change the world for the better. We are driven by our core values of agility, expertise, and trust. 

Clearance Requirement: Applicants selected will be subject to a government security investigation and must meet eligibility requirements, including U.S. Citizenship, for access to classified information; ability to obtain & maintain HSPD & Secret, preferred HSPD-12 & Secret Active.  

M.C. Dean seeks a Senior HVAC Mechanic to troubleshoot, maintain, and repair commercial HVAC and central plant systems in a mission-critical environment. This role requires independent diagnosis of complex failures and technical guidance for junior technicians.

Technical Skills:

• Refrigeration and DX: Diagnose faults using pressures, temperatures, superheat, and subcooling; perform leak detection, recovery, nitrogen pressure testing, micron evacuation/decay testing, charging, component replacement, and nitrogen-purged brazing. 
• Chillers and cooling towers: Troubleshoot air- and water-cooled chillers, flow deficiencies, safeties, and interlocks; interpret differential pressures, temperature differences, approach/range, and alarms. Service tower components and coordinate water treatment. 
• Hydronics and pumps: Diagnose air binding, cavitation, flow and heat-transfer problems; service seals, bearings, couplings, strainers, and valves; verify alignment, rotation, vibration, expansion tanks, and system pressures. 
• Boilers and steam: Troubleshoot heating equipment, heat exchangers, steam traps, pressure-reducing stations, and condensate returns; understand burner sequences, flame safeguards, low-water cutoffs, and interlocks. 
• Air distribution: Service AHUs, fan coils, VAVs, reheat, exhaust, and CRAC/CRAH equipment; diagnose airflow, static pressure, humidity, coil freezing, and condensate problems; understand economizers and building pressure. 
• Electrical and BAS: Troubleshoot motors, contactors, relays, overloads, control circuits, and VFDs using electrical meters. Interpret BAS trends, alarms, sensors, actuators, staging, lead/lag, resets, and commanded versus actual operation. 

Responsibilities and Site Requirements:

• Perform preventive/corrective maintenance and emergency repairs; identify recurring failure causes, recommend corrective work and spares, and verify safeties, operating sequences, and post-repair readings before return to service. 
• Coordinate approved shutdowns, restoration, vendors, and BAS changes with leadership and Work Control; guide technicians and record findings, labor, materials, and follow-up in InfraLink/CMMS. 
• Follow lockout/tagout, electrical safety, hot-work, confined-space, PPE, and refrigerant procedures. Work within training and authorization; never bypass safeties and refer specialized repairs to qualified personnel. 
• Meet government access/screening requirements; support assigned shifts, overtime, weekends, outages, and emergencies.
• Perform field duties in mechanical rooms and on rooftops, with reasonable accommodation as applicable. 

• Applicant must have a high school diploma or GED with a minimum of 8+ years of experience

  of hands-on HVAC/mechanical experience with substantial commercial, industrial, central plant, or mission-critical maintenance and repair. Residential-only experience does not qualify. 

• Applicants selected will be subject to a government security investigation and must meet eligibility requirements, including U.S. Citizenship, for access to classified information; ability to obtain & maintain HSPD & Secret, preferred HSPD-12 & Secret Active.

• Ability to interpret mechanical drawings, P&IDs, electrical schematics, equipment manuals, and sequences of operation; use diagnostic instruments and verify repairs.

• Demonstrated hands-on ability to troubleshoot, diagnose, maintain, and repair HVAC and mechanical equipment, rather than experience limited primarily to equipment monitoring or basic preventive maintenance.

• Working knowledge of chillers, boilers, pumps, cooling towers, AHUs, FCUs, VAVs, hydronic systems, piping systems, HVAC controls, and related mechanical infrastructure.

• Working knowledge of BAS/DDC systems and the ability to use BAS information as a troubleshooting and diagnostic tool.

• Ability to understand the relationship between mechanical, electrical, controls, instrumentation, and automation systems.

• Ability to proficiently use HVAC/mechanical diagnostic and test equipment and interpret test results.

• Experience identifying the root causes of equipment failures and recommending practical corrective actions.

• Ability to work independently and effectively troubleshoot equipment under time-sensitive or mission-critical conditions. 

Preferred Qualifications:

• Experience in occupied federal facilities, data centers, or hospitals; EcoStruxure, Niagara, Honeywell, or Siemens BAS familiarity; manufacturer training in chillers, boilers, VFDs, or precision cooling.

We offer an excellent benefits package including:

• A competitive salary

• Medical, dental, vision, life, and disability insurance

• Paid time off

• Tuition reimbursement

• 401k Retirement Plan

• Military Reserve pay offset

• Paid maternity leave

Abilities: 

• The position requires the ability to lift, carry, and move objects weighing up to [50 pounds] on a regular basis. Candidates must demonstrate physical strength and stamina to perform various tasks, including but not limited to, loading, and unloading, operating equipment, and assisting in the transportation of various materials. Proper lifting techniques and safety protocols must be followed to ensure personal and team safety.

• Relocates a 12-foot stepladder without assistance.

• Works at various heights up to 60 feet and can climb and maintain balance on scaffolds, aerial lifts, catwalks and all types of ladders.

• Walks, climbs, lifts, squats, crawls, kneels, pushes, pulls and reaches overhead on a routine and repetitive basis.

• Possess good vision (may be corrected vision), the ability to see in color, and the ability to hear and communicate in English.

• May use a standard ladder without exceeding the weight limit while carrying tools.

• Tell when something is wrong or is likely to go wrong.  It does not involve solving the problem, only recognizing there is a problem.

• Apply general rules to specific problems to produce answers that make sense.

• Combine pieces of information to form general rules or conclusions (including finding a relationship among seemingly unrelated events).

• See details at close range (within a few feet of the observer).

• Listen to and understand information and ideas presented through spoken words and sentences.