Air Handling Unit Replacement & Rebuild
Custom and packaged AHU replacements, fan array retrofits, coil and damper renewal, filtration upgrades and full controls integration.
Air handlers are the systems most facilities are afraid to touch: the unit serves an operating suite, a BSL-3 lab or half a trading floor, and it has to keep running. CMI replaces and rebuilds AHUs from 2,000 to 100,000+ CFM, including custom units that have to be knocked down and reassembled inside a penthouse or mechanical mezzanine.
Rebuild scope covers cooling and heating coil replacement, fan and bearing work, direct-drive fan array retrofits, VFDs, motor upgrades, damper and actuator replacement, casing and liner repair, drain pan replacement and epoxy coating, access door and gasket renewal, and filtration upgrades to MERV 14/15 or HEPA with the static-pressure analysis to prove the fan can carry it.
Full replacements include the pieces owners forget: structural dunnage and curb adaptation, duct transitions, chilled and hot water piping and controls valves, condensate, smoke and fire damper coordination, humidification, energy recovery, sound attenuation, and TAB and controls work so the new unit hits the design airflow and pressure relationships rather than merely running.
Scope & capabilities
- Packaged and custom AHU replacement, indoor and rooftop
- Chilled water, hot water, steam and DX coil replacement and coil cleaning
- VFDs, premium-efficiency motors, belt-to-direct-drive conversions
- MERV and HEPA filtration upgrades with static pressure analysis
- TAB, controls integration and pressure-relationship verification
- Knock-down and field-reassembled units for restricted mechanical rooms
- Direct-drive fan array (fan wall) retrofits, fan and bearing rebuilds
- Damper, actuator, linkage and economizer replacement
- Energy recovery wheels, humidifiers, sound traps and duct transitions
The technical envelope
- Airflow range
- 2,000 – 100,000+ CFM
- Configurations
- Draw-through, blow-through, fan array, 100% OA, ERV
- Filtration
- MERV 8 – 16, HEPA final filtration with DOP testing support
- Install methods
- Crane set, knock-down field assembly, curb adapters
- Verification
- TAB report, point-to-point controls, pressure relationships
Facility types
Air Handling Unit Replacement — straight answers
- Can you replace an air handler that serves an operating room?
- Yes — with a written phasing plan, temporary air or a redundant unit carrying the load, ICRA-compliant barriers, negative-pressure containment during construction, and cutover on nights or a scheduled OR shutdown. Pressure relationships and air changes are verified and documented before handback.
- Is a fan array retrofit better than replacing the whole unit?
- When the casing and coils are sound, a fan wall retrofit buys redundancy, lower sound and better part-load efficiency at a fraction of the cost and disruption. We evaluate casing condition, coil life and code exposure before recommending either path.
- How do you get a large unit into an existing mechanical room?
- Custom units are ordered knocked down in sections sized for your access path, rigged in piece by piece, and reassembled and sealed in place. We survey the route — doors, hatches, elevators, structural capacity — before the unit is released for fabrication.
Get a number you can budget against
We walk the plant before we price it. You get equipment condition, options, phasing and a schedule — not a guess with a contingency wrapped around it.