Facilities AI agent · Refrigerant management
Energy & HVAC Compliance AI Agent
Tally every refrigerant addition against the appliance that took it under 40 CFR 84.106, run the repair and verification clocks, and hold the plan an authorized company official signs.
- Typical delivery
- 4–6 weeks
- Deployment
- Your stack
- One signer
- Charge-clocked
- After launch
- Agent Care
What this agent does
Holds the charge ledger, never the signature
In
- 01
A charge is added, and § 84.106(d) starts the repair clock once the leak rate is crossed.
- 02
A leak rate is computed, and § 84.106(c)(2) sets a separate threshold per appliance type.
Reason
- 03
A repair closes, and § 84.106(d) wants a verification test inside it and another after it.
- 04
An inspection falls due, and § 84.106(g) fixes its frequency by appliance type and charge.
- 05
An appliance is newly installed above the size threshold, and § 84.108 wants detection on it.
Decide
- 06
An older appliance carries none, and § 84.108 sets 1 January 2027 for the ALD retrofit.
- 07
An ODS-charged chiller survives, and § 82.157 keeps it in part 82 on its own charge test.
Out
- 08
A covered building shuts its year, and NYC Admin. Code § 28-320.3.7 sets 1 May to file.
- 09
Execute write actions only inside the approval boundaries agreed during implementation.
Product statement
The agent holds the appliance ledger and runs the clocks. An authorized company official signs the plan and the chronic-leak report.
Example workflow
One appliance, charge to signature
- 1Charge evidence receivedContractor service tickets, cylinder records, inspection reports or detection alarms
- 2Appliance context assembledThe appliance, the site it serves, the part it answers to and the day the charge went in
- 3Leak-rate evidence draftedThe appliance, the additions behind it, the clocks now running and completeness
- 4Controls appliedThreshold checks, charge-provenance checks, clock checks and completeness confidence
No human action required
Stages 1 to 4 run unaided, and nothing is signed at any of them — the agent is assembling, and the engineering lane opens at the completeness gate.
Goes to the authorized company official to sign.
Adds an engineering read first.
Engineering review
The appliance is held with its additions, its clocks and the site it sits on.
Sign · Append evidence · Send to engineering
Signed — by an authorized company official
- 6Appliance and charge records updatedOnly where write access and records policy allow it
- 7Outcome evaluatedLeak-rate accuracy, clock coverage, engineer corrections and what the read found
Corrections
Each engineering correction is counted in the evaluation.
What should not run autonomously
Human approval stays in control
Outside the boundary — human approval required
8 items
- Signing a retrofit or retirement plan, § 84.106(l)(8).
- Signing the chronic-leak report under § 84.106(m)(4).
- Certifying a Local Law 97 report over a sealed attestation.
- Electing to retrofit an appliance rather than repair it.
Automation boundary
Agent acts unaided
- ✓Hold the appliance register and the full charge each one carries.
- ✓Attribute every refrigerant addition to the service ticket behind it.
- ✓Compute the leak rate per appliance and run the repair.
- ✓Watch both reporting deadlines and flag the appliance.
Nothing here is signed or filed except by a named person, inside the agreed boundaries.
- Judging whether a repair in fact closed the leak.
- Choosing the leak-rate calculation method.
- Requesting an extension of the repair clock.
- Changes to the appliance register or the charge ledger.
Example output
One appliance, annotated
Our maintenance triage agent works a tenant repair to a statutory clock; this record is what one refrigerant addition carried onto the ledger.
Ledger entry · single appliance
Illustrative example- Appliance
- Refrigerant added, § 84.106(l)(2)
- Recorded as
- Read against the leak-rate threshold
- Test
- Repair clock running
- Evidence of record
- Technician service ticket
- Confidence
- Held unsigned
- Held for
- The authorized company official, by name
As received
Taken from the service ticket and the cylinder record — it reaches as far as those sources do.
What the record holds
- Service ticket
- Cylinder record
- Full-charge document
Why no signature here
Whether an appliance is repaired is a § 84.106 judgement, not a model output.
What the score decides
Below the configured threshold an appliance picks up an engineering read before signature.
Action
SignAppend evidenceSend to engineeringValue
Where AI adds value
The same four claims, placed at the point in the workflow where each one applies.
Where the value lands
Value 01 – 04
Every addition
From the appliance that took it
Where the evidence is used
Our environmental permit reporting agent owns Title V, which binds because you hold a permit, whereas § 84.106 is self-executing and equipment-attached, clocked by the act of adding refrigerant — different signer, different deadline type, different evidence — and the energy-utilities pages are utility-side, not building-side.
A leak starts a clock
A mixed estate sits under both parts at once: § 82.157 became ODS-only at 85 FR 14171, 10 April 2020, yet § 84.102 still defines a certified technician by reference to § 82.161.
What was checked, and not found
The § 84.112 fire-suppression reporting date is single-sourced and is withheld here, the road and intermodal transport-refrigeration carve-out was still only proposed on 26 May 2026 and does not reach buildings, no petition for review against the subpart C rule could be confirmed either way, and OSHA 29 CFR 1926.1101 was not examined.
Build an evidence trail
The appliance, the charge added to it and the official who signed stay on the record.
Integrations
Typical integrations
Five system groups connect to the same agent. Which of them are in scope is decided in discovery.
Service and technician sources
- Contractor tickets
- cylinders
- Refrigerant addition records
Appliance and charge register
- CMMS
- asset register
- Full-charge documentation
Detection and monitoring
- ALD alarms
- calibration
- Audit and calibration logs
Agent
Energy and HVAC compliance
- Reads the additions
- Computes the leak rate
- Holds for the official
Metering and filing systems
- Benchmarking
- utility feeds
- Consumption and filing records
Observability & evaluation
- OpenTelemetry
- Langfuse
- Supported monitoring/evaluation sources
Integration availability depends on the client's existing systems and API access.
Agent controls
Six valves between the model and the official
Six valves opened in turn, the last barely at all. Whatever still flows is set out in the map below.
L6 · Outermost — last line of defence
Inward → L1 · closest to the model
- L1 – L2
- Test whether a leak rate may stand
- L3
- Puts the signature in a person's hands
- L4 – L5
- Keep the appliance and the charge behind it
- L6
- Leaves the plan unsigned when signals degrade
How Nestack evaluates it
Evaluate the whole assembly — not only the leak rate that comes out.
Coverage runs the whole depth of the workflow, and every layer is cut by slice.
Surface — the plan an inspector reads
- E1Final-output evaluationDid the ledger record what the appliance actually took?
- E2Step-level evaluationDid the agent read the right appliance, the right charge and the live register?
- E3Tool evaluationDid it read and write the correct appliance record and the correct ticket?
- E4Confidence calibrationDo low-confidence appliances actually attract more engineering corrections?
- E5Slice evaluationHow does performance change across specific appliance types?
- E6Business outcomeHow many appliances needed a correction before the official signed?
Floor — the ledger the owner answers for
Failure modes
Where each failure originates in the agent
Seven failure modes, each pinned to the stage where it first shows.
Agent lifecycle
Direction of processing →
01 · Retrieval
1 mode
- KK-03
Stale charge read
The full charge read is not the one now in the appliance.
Stage gathers
The appliance, the tickets, the charges and dates
02 · Reasoning
2 modes
- KK-04
Leak rate computed early
A rate is computed before the charge is complete.
- KK-06
Wrong part applied
An ODS appliance is worked under part 84.
Stage proposes
The appliances, their clocks and completeness
03 · Tool / write
2 modes
- KK-02
Thin file passed forward
A file moves on without the engineering read.
- KK-05
Bound to the wrong appliance
A charge is filed against the wrong unit.
Stage writes
Only where write access and approval policy allow it
04 · Output
1 mode
- KK-01
Signed, evidence unrecorded
The record shows a signature but not what supported it.
Stage returns
The plan an official signs and an inspector reads
05 · Change / Version
1 mode
- KK-07
Silent clock regression
A configuration change moves the clock, not the charge.
Stage tracks
Model, prompt, leak rules and ledger fields
- Sev-1 · a plan signed on no service record
- Sev-2 · wrong charge reaches the ledger
- Sev-3 · source degrades, plan held unsigned
Affected slices
Process refrigeration absorbs the corrections
An appliance-level charge-provenance figure can read clean while industrial process refrigeration carries most of the rework. Nestack reports the correction rate by appliance type, not only in total.
Slice performance — reported separately, not only in aggregate
Illustrative example| Slice | Failure rate | Lift | Lift vs. threshold | Status |
|---|---|---|---|---|
| Industrial process refrigeration | 8.8% | 3.6× | Review | |
| Commercial refrigeration | 6.3% | 2.6× | Review | |
| ODS-charged legacy appliances | 3.9% | 1.6× | Watch | |
| Comfort cooling chillers | 1.6% | 0.7× | Normal |
Bar: correction-rate lift vs. comfort cooling baseline · scale 0–4.0× · tick marks the 2.0× review threshold
2 of 4 slices over threshold
Evidence-linked improvement
What an untracked recharge costs
A cycle closes when the untracked recharge is a regression case. That suite is what the next appliance assessed is measured against.
Improvement cycle · five stages
Switchback — the path turns at Improve and returns at Learn
- 01
Detect
Correction rate rises on industrial process refrigeration.
- 02
Diagnose
The chiller topped up twice in a season, on a ticket nobody totalled, is read back until one cause remains.
- 03
Improve
The change ships numbered, and the appliances that forced it ride with it.
- 04
Verify
Nothing releases while one touched appliance case is still red.
- 05
Learn
It is retained for good, and the leak rules are amended in that same commit.
Learn → Detect
The return edge. The next appliance is measured against a suite one case longer.
Typical build scope
Twelve workstreams across six weeks
The build scope read against the delivery timeline. Week structure follows the six-week plan — discovery, sources, ledger assembly, evaluation, integration, then production validation and handover.
Workstream
Week 1Week 2Week 3Week 4Week 5Week 6
- 01Leak-rate-threshold and automation-boundary work.Week 1
- 02Service-ticket and cylinder sources.Week 1, Week 2
- 03Appliance-to-threshold and clock-coverage mapping.Week 1, Week 2
- 04Charge and addition ingestion.Week 2
- 05Appliance, charge and ticket binding.Week 2, Week 3
- 06Completeness scoring and review routing.Week 3
- 07Official signing workflow.Week 3, Week 4
- 08Asset-register system integration.Week 5
- 09Leak-rate and threshold cases.Week 4, Week 5
- 10Guardrails and signing controls.Week 4
- 11Appliance-trail instrumentation.Week 5, Week 6
- 12Deployment, documentation and Agent Care handover.Week 6
12 workstreams · 6 weeks · bar shows the weeks a workstream is active — several run in parallel
Final scope and sequence confirmed in discovery
Engagement tiers
What each tier includes
Rows are the capabilities named in each tier's scope. Higher tiers include everything below them.
| Capability✓ in scope · — not at this tier | PilotOne site, one year | ProductionProduction compliance workflow | AdvancedMultiple sites / portfolios |
|---|---|---|---|
| Introduced at Pilot | |||
| Ledger assembly to your appliances | ✓ | ✓ | ✓ |
| Authorized official release | ✓ | ✓ | ✓ |
| Charge-inventory baseline | ✓ | ✓ | ✓ |
| Introduced at Production | |||
| Reporting by appliance | — | ✓ | ✓ |
| Signing workflow in your systems | — | ✓ | ✓ |
| Approved write-back | — | ✓ | ✓ |
| Service-ticket integration | — | ✓ | ✓ |
| Introduced at Advanced | |||
| Multi-site portfolios | — | — | ✓ |
| Cross-year evidence packs | — | — | ✓ |
| Large appliance estates | — | — | ✓ |
| Multi-regime deadline controls | — | — | ✓ |
| Build price | From $5,000 | From $8,000 | Custom quote |
- Final build price
- Confirmed after discovery based on integrations, workflow complexity, appliance volume, approval controls and deployment requirements.
- Separate from build
- Build pricing is separate from recurring Agent Care, which covers managed monitoring, evaluations, incidents and verified improvements after launch.
What we need from you
What you bring, and what we build with it
Each input maps to a piece of build scope and a week in the delivery timeline.
You bring
We build with it
01Your appliances and the full charge each one carries
→Appliance-register mapping and charge capture
Week 102Representative service, cylinder and inspection records
→Record binding, threshold logic and the leak-rate baseline
Week 203Your calculation method under § 84.106(l)(3)
→Threshold mapping, clock binding and the automation boundary
Week 104Access to relevant APIs, feeds or exports
→Service, cylinder and register-source assessment, then integration setup
Week 205Appliances you would not want audited
→Leak cases and the evaluation run
Week 406What no service record may settle
→Completeness scoring, review routing, guardrails and release controls
Week 307An authorized company official who may sign
→Signing workflow, then pilot and production validation
Weeks 5–6
Nothing else is required
Deployment, documentation and Agent Care handover are ours.
Delivery timeline
Four phases across six weeks
These widths measure the work rather than the page, which is why a single week carries two phases.
Phase
W1
W2
W3
W4
W5
W6
- DiscoveryW1
- BuildW2 – W3
- EvaluateW4 – W5
- Pilot & LaunchW5 – W6
Week focus
W1Refrigerant workflow discovery, threshold mapping and the automation boundary
W2Source integration and the charge-provenance baseline
W3Ledger assembly, clock logic and release controls
W4Evaluation suite, leak-rate cases and failure-mode testing
W5Register integration, pilot appliances and targeted corrections
W6One compliance year run under the authorised official, then Agent Care handover
- Reading the band
- Each bar covers only the weeks its own work is named for. Week five holds two because the work holds two.
- At the end of W6
- When the appliance record validates, Agent Care takes the agent on.
- Duration
- Six-week plan shown · typical delivery 4–6 weeks depending on scope confirmed in discovery.
Next step · Facilities AI agent
Build a refrigerant agent around the chiller that was topped up twice and totalled once.
Show us one appliance and the charge it took. An authorized company official signs the retrofit or retirement plan under § 84.106(l)(8) and the chronic-leak report under § 84.106(m)(4); in New York City a registered design professional certifies the filing.
- Typical delivery
- 4–6 weeks
- Deployment
- Your appliances
- One signer
- Charge-clocked
- After launch
- Agent Care available
Nestack Agents · Refrigerant management
AGT-AF-06 · Agent Care available after launch