How We Migrated Piper Spirit From LonWorks to BACnet/IP
The legacy system was working fine. That wasn’t the point.
The original 2007 BAS install at Piper Spirit — Athena Engineering’s headquarters at 456-460 East Foothill Boulevard in San Dimas — ran on LonWorks. The choice made sense at the time. LonWorks was the dominant building-controls protocol of the era, and Schneider’s I/A Series controllers (the platform we installed across both buildings) used it as the standard backbone.
Eighteen years later, the system still worked. Setpoints held. Schedules ran. The supervisor came up every morning. From a strict performance standpoint, the original install was fine. The migration wasn’t driven by anything failing. It was driven by what was getting harder.
What was getting harder.
- Replacement parts were harder to source. LonWorks devices were no longer in the active manufacturing pipeline for several lines we depended on. Spares meant the gray market or pulled-from-decom inventory.
- Integration with newer products was painful. Cloud platforms, IP-based security stacks, modern Schneider EcoStruxure modules — most of them expected BACnet/IP. Bridging to LonWorks always added a layer of gateway, a layer of risk, and a layer of cost.
- The talent pool was tightening. Newer techs train on BACnet. Senior techs who still fluently troubleshoot LonWorks are a finite group.
- The supervisor was outgrowing the field bus. EcoStruxure Building Operation v7.0 is built with BACnet/IP in mind. Asking it to manage a LonWorks stack underneath worked, but it wasn’t the way the platform wanted to be used.
None of these were emergencies. All of them were headed in one direction. We decided to move while it was still a project, not a fire drill.
What we did.
In 2025, our controls crews migrated the entire two-building campus BAS — every device, every field bus run, every supervisor point — from LonWorks to BACnet/IP. The supervisor stayed on Schneider EcoStruxure Building Operation v7.0. Everything below it now speaks BACnet/IP natively.
Scope of work, in plain terms:
- Replaced the original I/A Series LonWorks controllers with Schneider IP-native controllers compatible with EcoStruxure v7.0.
- Pulled new field wiring where the existing topology didn’t carry over cleanly. Reused infrastructure where it did.
- Re-mapped and re-pointed the entire supervisor — every point, every alarm, every schedule, every trend.
- Re-commissioned the chilled water plant, the variable air volume system, and all interconnected systems against the new control logic.
- Verified the AccessXpert and Verkada integrations against the new BACnet/IP supervisor stack.
The work was performed by Athena Engineering’s own controls technicians. The same techs who handle legacy migrations on client buildings across Southern California. We didn’t subcontract the BAS work on our own headquarters — that would have defeated the whole point.
A few decision points worth flagging.
Owners considering a similar retrofit usually face the same handful of judgment calls. Here’s how we handled them on our own building.
Phased or all-at-once?
All-at-once. The buildings stayed occupied throughout. Coordination was tight, and there were a few uncomfortable hours during cutover. But phasing a migration where the legacy and new protocols have to coexist on the same supervisor adds genuine risk — every bridge layer is a place something can drift. For most owner-occupied buildings of this scale, we’d recommend the same approach. For larger campuses or 24/7 critical environments, the calculus changes.
Reuse existing controllers, or replace?
Replace. We did the math both ways. The bridging-and-keeping path looked cheaper on paper, but it locked us into the same legacy headache we were trying to get out of. The replacement path was more capital up front and substantially less liability over the next ten years. Numbers favor replacement on almost every retrofit at this scale unless the existing controllers are unusually new.
Re-commission or trust the legacy sequences?
Re-commission. Always. The original 2007 sequences had drifted over eighteen years of operations, manual overrides, and one-off field tweaks. The supervisor was reflecting a building that no longer existed in quite the same way. Re-commissioning during the migration window was the right time to clean it up. We caught two issues that had been silently costing energy for years.
What we’d tell an owner looking at the same move.
It’s not as scary as the cost estimate looks on first read. The labor scope is real, and the cutover window takes planning. But every owner we’ve taken through a migration like this — on a building they care about, with a controls partner they trust — comes out the other side relieved they did it. The system is faster, integrations are cleaner, and the next ten years of operations are simpler. The version we did on ourselves was the same version we recommend.
If you’re sitting on an aging LonWorks install, an old TAC Vista, an Andover Continuum system, or a pneumatic plant that needs to come forward, this is the kind of project we built the firm to do. Come walk through Piper Spirit. The buildings are open to clients on Foothill Boulevard, five minutes off the freeway interchange. We’ll show you the supervisor screen, the panels, and the receipts.
