A magnetic bearing chiller inverts almost every rule a facilities engineer knows about compressor maintenance. There is no oil to sample. No filter to swap. No mechanical bearing to lubricate. The whole "quarterly compressor PM" list evaporates — and it's replaced by a different discipline entirely: watching controls, protecting the DC bus, testing the backup capacitor bank and keeping the touchdown bearings ready for a power event that may never come. This guide walks the model using OXMAINT AI, the AI-powered CMMS for chiller reliability teams.
Magnetic Bearing Chiller Maintenance: Turbocor Compressor PM Program
OXMAINT AI, the AI-powered CMMS/maintenance management software, connects the full magnetic bearing chiller workflow on one platform — controller telemetry and inspections in, defects raised and prioritised by criticality, work orders assigned to chiller techs, and preventive & predictive PM cadence tuned for the electronic-first Turbocor reality.
The Old PM List vs the Turbocor PM List
A conventional centrifugal chiller PM list is 70% mechanical. A Turbocor PM list is 70% electronic. If your team is still walking the old checklist, they're either doing work that doesn't exist or missing work that does. OXMAINT AI ships a Turbocor-specific template that inverts the model. Sign up free and load the Turbocor template in OXMAINT AI.
- Oil sampling and change intervals
- Oil filter differential pressure
- Oil cooler and pump PM
- Journal bearing clearance checks
- Shaft alignment and coupling
- Gearbox lube service
- Controller firmware and log review
- DC bus capacitor health test
- UPS / backup ride-through validation
- Magnetic bearing position sensors
- VFD / IGBT thermography
- Touchdown bearing inspection
Anatomy of a Magnetic Bearing Chiller
Understanding what to maintain starts with understanding what's actually inside. A Turbocor compressor is a permanent-magnet motor with a two-stage centrifugal impeller levitated on active magnetic bearings, driven by a VFD and controlled by an onboard microprocessor. OXMAINT AI holds each subsystem as its own asset with its own PM sub-template. Book a demo to see the subsystem asset tree.
The Coastdown Story — Why Backup Power Matters
The single most important thing to understand about a magnetic bearing chiller: when power fails, the levitation field collapses. The compressor is spinning at 40,000+ RPM. It has to touch down safely on ceramic backup bearings or the shaft crashes into stator surfaces. OXMAINT AI treats coastdown readiness as its own PM stream. Start free and set up your coastdown PM in OXMAINT AI.
Coastdown Isn't Optional. Neither Is Its PM.
OXMAINT AI holds capacitor bank tests, UPS ride-through validation and touchdown bearing inspection as scheduled PMs — so a power event doesn't discover the failure for you.
The Turbocor PM Cadence Library
A working magnetic bearing chiller runs on a nested cadence — controller log review daily, electrical checks quarterly, deeper inspections annually. OXMAINT AI ships the cadence as a default template. Book a demo to walk the cadence library.
| Cadence | Task | Subsystem | Method / Signal |
|---|---|---|---|
| DAILY | Controller log review — alarms, trends, faults | CTL | Remote dashboard read |
| DAILY | Chilled/condenser water temp + delta-T | System | BMS trend |
| WEEKLY | Bearing position sensor drift check | MBR | Controller output logs |
| WEEKLY | Refrigerant subcool / superheat trend | System | Controller telemetry |
| MONTHLY | VFD / IGBT thermography under load | VFD | IR camera + trend log |
| MONTHLY | Air filter / heat-exchanger cleanliness | System | Visual + dP check |
| MONTHLY | UPS runtime + battery voltage check | BUS | UPS controller test |
| QUARTERLY | DC bus capacitor bank health test | BUS | Capacitance + ESR meter |
| QUARTERLY | Coastdown ride-through validation | BUS + MBR | Controlled trip test per OEM |
| QUARTERLY | Firmware version review + update planning | CTL | OEM release notes |
| ANNUAL | Touchdown bearing inspection + wear check | TDB | Compressor open-up per OEM |
| ANNUAL | Refrigerant leak survey + purge unit PM | System | Portable detector sweep |
| ANNUAL | Eddy-current tube inspection (evap + cond) | System | Certified NDT vendor |
The Fault Signal Map — What the Controller Actually Tells You
Turbocor faults arrive as codes on the controller. Reading them fast, and mapping them to the right PM domain, is where downtime is won or lost. OXMAINT AI ships a fault-code library that turns codes into WOs with the right template. Sign up free and load the fault-code library in OXMAINT AI.
The 4 Critical Failure Watch Points
Four things kill a magnetic bearing chiller if unattended. All four are preventable, and all four are on the OXMAINT AI default watch list. Book a demo to see the critical watch list.
What OXMAINT AI Gives a Chiller Reliability Team
Purpose-built for the electronic-first chiller reality — one platform behind the controllers, capacitor banks, VFDs and touchdown bearings. Start free and load your chiller plant into OXMAINT AI.
Our team was still walking a 1998 centrifugal PM checklist on 2020 magnetic bearing machines. Everyone knew it — we just hadn't rebuilt the checklist. Once the CMMS held a real Turbocor template, the conversation moved from "when did we last change the oil" (never) to "when did we last test the capacitor bank" (turns out, a while). The chillers didn't change. Our understanding of them did.
Frequently Asked Questions
Controls. Bus. Bearings. Refrigerant. One Platform.
Move your magnetic bearing chiller operation onto OXMAINT AI — Turbocor-specific PM template, fault-code library, coastdown PM stream and a fleet view of every chiller on the estate.
