CF ChatterFix
Support Equipment

Makeup Air Unit Maintenance

Makeup air is the system nobody thinks about until the building goes negative and doors get hard to open, exhaust fans stop pulling and combustion appliances start backdrafting. Because its failure shows up as symptoms elsewhere in the building, it is diagnosed late and often replaced rather than serviced.

Tracked Components
Scheduled PMs 1
Industries HVAC & Building Services Contractors

How Makeup Air Unit Actually Fails

The failure modes worth designing a maintenance schedule around — in rough order of what they cost when they happen.

  • Burner and ignition faults leaving the space under negative pressure
  • Filter loading that quietly starves the unit of the airflow it was sized for
  • Damper and actuator seizure, especially on outdoor-air intakes
  • Freeze protection failure on the coil in cold-weather operation
  • Belt and bearing wear on the supply fan

What To Measure

Recording that a PM was "done" tells you nothing next quarter. These are the readings that let you see a failure coming — and the reason ChatterFix captures measurements against the asset rather than just completions.

  • Building pressure relative to outside — the whole purpose of the unit
  • Differential pressure across filters trended rather than read once
  • Burner combustion figures and stack temperature logged at each service
  • Damper travel and the outdoor-air fraction actually being delivered
  • Freezestat function proven before the heating season, not during it

Spares Worth Stocking

The parts whose absence turns a short repair into a long outage.

Preventive Maintenance Schedule

The PMs ChatterFix schedules against this equipment, with intervals and time estimates.

Common Questions

What maintenance does makeup air unit need?
ChatterFix schedules 1 routine against this asset: rooftop unit seasonal changeover (semi-annual). The readings that matter most are building pressure relative to outside — the whole purpose of the unit.
How does makeup air unit usually fail?
The most common modes are: burner and ignition faults leaving the space under negative pressure; filter loading that quietly starves the unit of the airflow it was sized for; damper and actuator seizure, especially on outdoor-air intakes; freeze protection failure on the coil in cold-weather operation; belt and bearing wear on the supply fan. Most of these degrade gradually rather than failing outright, which is what makes interval-based inspection worthwhile.
What spare parts should we stock?
Filters, Belts, Bearings, Ignition components, Damper actuators. The test is lead time, not cost: stock the part whose absence turns a two-hour repair into a two-week outage, even if it is cheap.
Can I track this in ChatterFix?
Yes. Pick your industry at signup and makeup air unit is created as an asset , with its PM schedule already attached. Technicians then log readings and findings against it by voice rather than typing them in.

Where It Fits

Get Makeup Air Unit Into A Real CMMS

ChatterFix builds this asset, its components, and its PM schedule automatically when you pick your industry — then your technicians update it by talking, not typing.