Senior HVAC Mechanic - Washington, DC

M.C. Dean, Inc•Washington, DC

About The Position

M.C. Dean seeks a Senior HVAC Mechanic to troubleshoot, maintain, and repair commercial HVAC and central plant systems in a mission-critical environment. The role includes independently diagnosing complex failures and providing technical guidance to junior technicians. Duties span refrigeration and DX systems; chillers and cooling towers; hydronics and pumps; boilers and steam; air distribution; and electrical and BAS controls. The mechanic performs preventive and corrective maintenance, emergency repairs, and follow-up verification of equipment safeties, operating sequences, and readings before returning systems to service. The role also involves identifying recurring failure causes, recommending corrective work and spare parts, coordinating approved shutdowns, restoration, vendors, and BAS changes with leadership and Work Control, and documenting findings, labor, materials, and follow-up in InfraLink/CMMS. The position requires compliance with safety procedures and government access and screening requirements. Field duties take place in mechanical rooms and on rooftops, with reasonable accommodation as applicable. The employee must support assigned shifts, overtime, weekends, outages, and emergencies.

Requirements

High school diploma or GED.
At least 8 years of hands-on HVAC/mechanical experience, including substantial commercial, industrial, central plant, or mission-critical maintenance and repair; residential-only experience does not qualify.
A current Journeyman License from a U.S. state or territory, or VMET certification with equivalent experience, or equivalent training and certifications plus verifiable minimum 5 years of commercial or industrial experience in an environment where a license was not required.
Meet government security investigation and eligibility requirements, including U.S. Citizenship, for access to classified information; ability to obtain and maintain HSPD and Secret is required, with HSPD-12 and active Secret preferred.
Ability to interpret mechanical drawings, P&IDs, electrical schematics, equipment manuals, and sequences of operation; use diagnostic instruments and verify repairs.
Demonstrated hands-on troubleshooting, diagnosis, maintenance, and repair of HVAC and mechanical equipment; experience limited primarily to monitoring or basic preventive maintenance is insufficient.
Working knowledge of chillers, boilers, pumps, cooling towers, AHUs, FCUs, VAVs, hydronic and piping systems, HVAC controls, and related mechanical infrastructure.
Working knowledge of BAS/DDC systems and ability to use BAS information for troubleshooting and diagnosis.
Ability to understand relationships among mechanical, electrical, controls, instrumentation, and automation systems.
Proficiency using HVAC/mechanical diagnostic and test equipment and interpreting test results.
Experience identifying root causes of equipment failures and recommending practical corrective actions.
Ability to work independently and troubleshoot effectively under time-sensitive or mission-critical conditions.
Ability to lift, carry, and move objects weighing up to 50 pounds regularly and follow proper lifting techniques and safety protocols.
Ability to relocate a 12-foot stepladder without assistance; work at heights up to 60 feet and climb and maintain balance on scaffolds, aerial lifts, catwalks, and ladders.
Ability to walk, climb, lift, squat, crawl, kneel, push, pull, and reach overhead routinely and repetitively.
Good vision, which may be corrected, ability to see color, and ability to hear and communicate in English.
Ability to use a standard ladder without exceeding its weight limit while carrying tools.
Ability to recognize when something is wrong or likely to go wrong; apply general rules to specific problems; combine information to form conclusions; see details at close range; and listen to and understand spoken information and ideas.

Nice To Haves

Experience in occupied federal facilities, data centers, or hospitals.
Familiarity with EcoStruxure, Niagara, Honeywell, or Siemens BAS.
Manufacturer training in chillers, boilers, VFDs, or precision cooling.
HSPD-12 and active Secret clearance.

Responsibilities

Troubleshoot, maintain, and repair commercial HVAC and central plant systems in a mission-critical environment.
Independently diagnose complex system failures and provide technical guidance to junior technicians.
Diagnose refrigeration and DX faults using operating pressures, temperatures, superheat, and subcooling; perform leak detection, refrigerant recovery, nitrogen pressure testing, evacuation and decay testing, charging, component replacement, and nitrogen-purged brazing.
Troubleshoot air- and water-cooled chillers, cooling-tower components, flow deficiencies, safeties, interlocks, alarms, and operating measurements; coordinate water treatment.
Diagnose hydronic system problems and service pumps, seals, bearings, couplings, strainers, and valves; verify alignment, rotation, vibration, expansion tanks, and system pressures.
Troubleshoot boilers, heat exchangers, steam traps, pressure-reducing stations, condensate returns, burner sequences, flame safeguards, low-water cutoffs, and interlocks.
Service AHUs, fan coils, VAVs, reheat, exhaust, and CRAC/CRAH equipment; diagnose airflow, static pressure, humidity, coil freezing, condensate, economizer, and building-pressure issues.
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.
Perform preventive and corrective maintenance and emergency repairs; identify recurring failure causes and recommend corrective work and spare parts.
Verify safeties, operating sequences, and post-repair readings before returning equipment to service.
Coordinate approved shutdowns, restoration, vendors, and BAS changes with leadership and Work Control.
Guide technicians and document 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, do not bypass safeties, and refer specialized repairs to qualified personnel.
Meet government access and screening requirements and support assigned shifts, overtime, weekends, outages, and emergencies.
Perform field duties in mechanical rooms and on rooftops.