A building engineer can usually tell you which chiller "feels old" or which AHU "always acts up in summer." What she cannot tell you, without digging through a year of work orders, is exactly how many operating hours pass between failures on that unit, or whether the gap is shrinking. That number has a name — Mean Time Between Failures — and it is the single metric that turns a gut feeling about a problem asset into a documented case for repair, replacement, or a serious conversation with a vendor. OxMaint calculates MTBF automatically for every asset in your portfolio, from a single work order log.
Reliability Tracking — OxMaint CMMS
Know Which Assets Are Failing Faster — Before The Next Breakdown
Automatic MTBF and MTTR per asset. Failure trend alerts. Preventive maintenance tied to real reliability data, not guesswork.
15-30%
Yearly MTBF decline typical on aging equipment that is never trended
4x
Cost gap between a scheduled repair and an emergency breakdown call
1 Log
Every work order becomes a failure event the moment it is closed
14 Days
Typical time to have MTBF live across an entire facility portfolio
Why A Spreadsheet Will Always Lie To You About MTBF
MTBF is a simple idea — total operating hours divided by the number of failures — but the number is only as honest as the data feeding it. A missed work order, a technician who logs "fixed" instead of the actual fault, or a timestamp entered a day late all quietly inflate reliability and hide the asset that is actually falling apart. Facility teams running MTBF off spreadsheets almost always discover, the first time they audit it, that their real failure rate was worse than the paper trail showed.
The Metric In Plain Terms
Total Operating Hours
2,400 hrs
÷
Failure Events Logged
6
=
MTBF
400 hrs
Pair MTBF with Mean Time To Repair and you get the full picture — how often an asset fails, and how long it takes to get it running again. Together they define equipment availability.
Manual MTBF vs OxMaint-Automated MTBF
| Dimension | Spreadsheet Tracking | OxMaint Automated Tracking |
|---|---|---|
| Failure event capture | Manually entered, often missed or delayed | Logged automatically the moment a work order closes |
| Timestamp accuracy | Rounded to the day, sometimes backdated | Recorded to the minute at every status change |
| Asset-level visibility | One fleet-wide average that hides problem units | MTBF calculated per asset, per building, per system |
| Trend detection | Noticed months after reliability started dropping | Declining MTBF flagged as soon as the pattern forms |
| PM budget justification | Anecdotal — "this unit breaks a lot" | Documented reliability history behind every CapEx ask |
How OxMaint Builds MTBF Without Extra Work
1
Every Asset Gets A Failure Log
Chillers, AHUs, pumps, generators, elevators, and electrical gear are each set up as individual assets with their own operating history from day one.
2
Work Orders Become Data Points
When a technician closes a reactive work order, that event, its timestamp, and its failure category are captured automatically — no separate reliability form to fill out.
3
MTBF And MTTR Calculate Live
Both figures update as new events log, per asset and rolled up by building, floor, or system, instead of being recalculated by hand once a quarter.
4
Declining Trends Trigger A Review
When an asset's MTBF drops against its own baseline, it is flagged for a maintenance strategy review before it becomes the facility's next emergency call.
What A Healthy MTBF Looks Like By Asset Type
HVAC & Rooftop Units
Reactive-managed buildings trend low
Facilities running HVAC on a reactive-only program consistently show shorter intervals between compressor, belt, and control failures than buildings on a structured PM cycle.
Pumps & Motors
300 – 1,200 operating hours
High-duty-cycle rotating equipment varies widely by maintenance maturity — the gap between well-serviced and neglected units is usually the biggest MTBF swing in a facility.
Backup Generators
Failure often shows up at test, not use
Generators can look reliable for years and still fail on the one day they're needed, which is why load-test outcomes deserve their own place in the failure log.
Elevators & Conveyances
4+ callbacks a year is a warning sign
A rising callback rate on a single car is one of the clearest early indicators that a component is heading toward failure faster than the maintenance cycle can catch it.
Stop Averaging Away Your Worst Asset
A single fleet-wide MTBF number hides the one chiller or one elevator that is actually dragging the whole portfolio down. See every asset ranked by reliability, not buried in an average.
What Facility Teams See After 90 Days
Per-Asset
MTBF replaces a single misleading portfolio-wide average
Live
Reliability trends update with every closed work order, not quarterly
Earlier
Declining assets get flagged for review before the next breakdown call
Documented
Every CapEx and PM budget request backed by real failure history
We used to argue about which building was the "problem site" from memory. Now every asset has its own MTBF trend line, and the argument is over — the data tells us exactly where PM dollars need to go first.
Regional Facility Operations Manager · Multi-site commercial portfolio
Frequently Asked Questions
It calculates automatically. Every closed work order becomes a timestamped failure event, and MTBF updates per asset without a separate reliability form. Start free to see it run on your own asset list.
Yes. MTBF is calculated per asset, then rolled up by system, floor, building, or portfolio, so one reliable unit never hides a failing one in a fleet-wide average.
Yes. Repair duration is captured on the same work order, so MTBF and MTTR are always paired, giving a complete picture of both failure frequency and recovery speed.
Most teams are live across their full asset list within about two weeks. Trends become meaningful as failure history accumulates, and past work order data can be imported to speed this up. Book a demo to see a rollout plan for your portfolio.
Yes. When an asset's MTBF drops against its own baseline, it is flagged for review so the maintenance strategy can be adjusted before the next failure, not after.
Reliability Tracking — OxMaint CMMS
Turn Every Work Order Into Reliability Data
Automatic MTBF and MTTR per asset. Early warning on declining reliability. A documented case for every repair, replace, or budget decision.
