Prevent belt and bearing failures before they stop your fans. This digital-ready checklist covers belt tension, pulley alignment, bearing vibration, and lubrication for every AHU, cooling tower, and fan coil unit in your building. OxMaint's preventive maintenance platform turns every checklist item into a scheduled work order with timestamped technician sign-off. Book a demo to see how OxMaint automates belt and bearing PM across your HVAC fleet.
interactive checklist · fans and motors
HVAC Belt and Bearing Maintenance Checklist
Belt tension · Pulley alignment · Bearing vibration · Lubrication · Replacement scheduling — all tasks assignable in OxMaint
live checklist snapshot · today
AHU-01 · Level 2Belt tensionPass
AHU-04 · Level 4Bearing vibration3.8 mm/s flag
CT Fan-2 · RoofPulley alignmentmisaligned work order
FCU-B7 · BasementBearing lubedcomplete
92%
checklist compliance
3
auto work orders today
35%
of fan failures are belt or bearing related — most preventable category
5x
cost difference: planned belt vs emergency repair plus downtime
18 min
average time to complete full AHU belt and bearing inspection
100%
compliance when OxMaint auto-assigns every checklist
HVAC belt and bearing checklist — every task, every asset
belt inspection
1
Belt tension
Measure with tension gauge or deflection. Pass: 10-15mm per 300mm span. Monthly
Measure with tension gauge or deflection. Pass: 10-15mm per 300mm span. Monthly
2
Belt condition — cracks or glazing
Visual: no cracks, fraying, glazing. Monthly
Visual: no cracks, fraying, glazing. Monthly
3
Belt slippage or squealing
Listen at startup. Pass: no audible squeal. Monthly
Listen at startup. Pass: no audible squeal. Monthly
4
Belt type and size match
Verify cross-section and length match OEM spec. On replacement
Verify cross-section and length match OEM spec. On replacement
5
Multi-belt matching
All belts from a matched set — no mixing lengths. On replacement
All belts from a matched set — no mixing lengths. On replacement
6
Belt guard condition
Guard present, secure, no distortion. Monthly
Guard present, secure, no distortion. Monthly
pulley and drive alignment
7
Pulley angular alignment
Use straight-edge or laser. Pass: misalignment less than 0.5 degrees. Quarterly
Use straight-edge or laser. Pass: misalignment less than 0.5 degrees. Quarterly
8
Pulley parallel alignment
Straight-edge contacts all four pulley face points. Quarterly
Straight-edge contacts all four pulley face points. Quarterly
9
Pulley groove wear
Inspect groove profile — no belt bottoming out. Annually
Inspect groove profile — no belt bottoming out. Annually
10
Pulley set-screw torque
Torque to OEM spec. Quarterly
Torque to OEM spec. Quarterly
11
Motor slide base condition
Clean, lubricate, locking bolts tight. Quarterly
Clean, lubricate, locking bolts tight. Quarterly
bearing inspection and lubrication
12
Bearing vibration level
Measure in mm/s RMS. Alert at 3.5, replace at 5.0 or higher. Monthly
Measure in mm/s RMS. Alert at 3.5, replace at 5.0 or higher. Monthly
13
Bearing temperature
Infrared thermometer. Pass: below 85 degrees Celsius housing. Monthly
Infrared thermometer. Pass: below 85 degrees Celsius housing. Monthly
14
Bearing noise (runout)
Listen for grinding, rumbling. Smooth only. Monthly
Listen for grinding, rumbling. Smooth only. Monthly
15
Grease lubrication
Use correct grease type and quantity per OEM interval. Per OEM schedule
Use correct grease type and quantity per OEM interval. Per OEM schedule
16
Bearing housing condition
No cracks, fretting marks, or grease leaks. Quarterly
No cracks, fretting marks, or grease leaks. Quarterly
17
Shaft seal condition
No grease leaking past lip seal. Quarterly
No grease leaking past lip seal. Quarterly
Digital checklists — auto-scheduled, auto-tracked
OxMaint assigns every belt and bearing task to your technicians, logs vibration readings, and auto-creates work orders when a measurement exceeds tolerance. No missed inspections, no surprise failures.
Belt and bearing failure: before vs with OxMaint
Without OxMaint — reactive
Belt tension last checked 9 months ago — no record
Bearing vibration not measured since commissioning
Technician memory is the only PM trigger
Belt fails mid-shift — AHU down, zone without cooling
Emergency call-out: $1,800 unplanned repair plus 6 hours downtime
No data on how long failure was developing
With OxMaint — preventive
Belt tension auto-scheduled monthly — every AHU tracked
Bearing vibration logged monthly — trend visible over time
OxMaint generates work order 30 days before replacement interval
Belt replaced in planned access window — zero disruption
Planned replacement: $180 belt plus 45 minutes labor
Full fault trend and history logged to asset record
Replacement intervals by asset type
| HVAC Asset | Belt Replacement | Bearing Relubrication | Bearing Replacement | Vibration Alert |
|---|---|---|---|---|
| AHU Supply Fan | 12-18 months | 6 months / 4,000 hrs | 5-8 years | 3.5 mm/s |
| AHU Return Fan | 12-18 months | 6 months / 4,000 hrs | 5-8 years | 3.5 mm/s |
| Cooling Tower Fan | Annual (pre-summer) | 3 months | 3-5 years | 4.0 mm/s |
| Chilled Water Pump | n/a (direct drive) | 6 months | 4-6 years | 2.8 mm/s |
| Exhaust or Extract Fan | 12 months (kitchen: 6) | 6 months | 5-7 years | 3.5 mm/s |
| Condenser Fan | Annual pre-summer | 6 months | 4-6 years | 3.5 mm/s |
"
Belt and bearing failures are the most embarrassing category of HVAC breakdown — embarrassing because they are almost entirely preventable, the inspection takes less time than the emergency callout paperwork, and the part costs a fraction of the repair bill. Facilities with structured, digitally-tracked belt and bearing checklists see failure rates below 2 percent per year. Facilities relying on technician memory see failure rates of 15 to 25 percent. The difference is not skill — it is system. OxMaint creates the system: the checklist appears on the technician's phone, the reading gets logged, and the work order for the at-risk bearing is raised before the bearing fails.
Paul Greenaway, CIBSE, IEng
Principal HVAC Maintenance Engineer · 24 years fan system maintenance, vibration analysis, rotating equipment asset management
Frequently asked questions
How does OxMaint auto-generate work orders from checklist readings?
Each checklist item can have a pass/fail threshold (for example, bearing vibration greater than 3.5 mm/s). When a technician enters a reading outside tolerance, OxMaint instantly creates a corrective work order — assigned to the right technician, linked to the asset, with the inspection record attached. This closes the loop from inspection to repair without manual follow-up. Start a free trial to configure threshold-based auto work orders.
Can OxMaint track vibration trends over time for each bearing?
Yes — every numeric reading (vibration, temperature, deflection) is stored against the asset record with a timestamp. Supervisors can view trend charts showing, for example, drive-end bearing vibration on AHU-04 over 12 months, spotting the gradual rise from 1.2 mm/s to 3.8 mm/s that signals end of useful life. This enables condition-based replacement instead of arbitrary fixed intervals. Book a demo to see asset condition trends.
How do I manage checklists across dozens of AHUs with different schedules?
OxMaint supports asset-specific PM schedules. Each AHU can have its own monthly belt check, quarterly full inspection, and annual service — all generating work orders on the correct cycle automatically. The dashboard shows completion rates, overdue tasks, and trend data across your entire fleet without paper reports. Try OxMaint free and set up your first AHU checklist in minutes.
oxmaint · hvac belt and bearing pm
Every belt checked. Every bearing trended. Every failure prevented.
OxMaint digitises your belt and bearing maintenance programme — auto-scheduling inspections, logging readings, flagging anomalies, and creating corrective work orders before the fan stops.
