RCx Analysis & Reporting

Phased workflow for retro-commissioning analysis projects — from equipment investigation through final report delivery. Covers ECM/FIM discovery, savings quantification, cost estimation, and report assembly.

For SOO development, functional testing, and general Cx procedures: see commissioning-reports skill.

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RCx Workflow Architecture

Each phase runs in a clean context window with structured knowledge capture. Session outputs are saved as markdown files that feed subsequent phases.

Phase 1: Equipment Analysis & SOO Development

Covers both new and existing equipment. Goal: build the data foundation for ECM/FIM discovery.

Equipment Analysis (New or Existing):

• Collect equipment schedules from mechanical drawings and submittals
• Site walk data collection: nameplate data, field conditions, photos
• BAS trend data request, collection, and initial review
• Document design-vs-current comparisons for each major system

SOO Analysis & Development:

• Review existing SOOs from EoR or controls contractor (if any)
• Identify gaps: missing sequences, outdated references, unaddressed modes
• Develop recommended SOOs where EoR drawings contain none (invoke commissioning-reports skill)
• Deliver SOOs to project team for review

Session Architecture: One session per system or logical group. Output files:

• equipment/<system>/design-vs-current.md
• session-outputs/phase-1-<system>-output.md
• SOO deliverables (if applicable)

Phase 2: ECM/FIM Consolidation Rules & Discovery Framework

BEFORE starting system-by-system discovery, establish consolidation rules that govern how findings are organized. This prevents list bloat and eliminates rework at the costing phase.

Consolidation Rules (define upfront):

Rule	Example	Treatment
Same root cause across multiple systems	Economizer locked on all 4 AHUs	One ECM (building-wide)
Equipment being replaced	RTU findings when replacement is planned	Narrative summary paragraph — owner discretion
Same failure mode, same trade	Sensor failures across terminal units	One FIM grouped by coordination owner
Already-delivered items	SOOs provided to project team	Appendix reference, not ECM/FIM line item
Owner-decision-dependent	Scheduling changes requiring owner input	Flag in list, note "requires owner authorization"

Discovery Framework Setup:

• Create ECM/FIM register template with global numbering scheme
• Define output file naming convention: phase-2-<N>-<system>-output.md
• Define "Finding Block Format" block structure for each finding (Findings -> Modified SOO -> Affected Equipment)
• Identify systems to be investigated and session order

Phase 3: System-by-System ECM/FIM Discovery

One system per session (clean context window). Apply consolidation rules AS items are identified — don't create separate line items for findings that match a consolidation rule.

Per-Session Workflow:

1. Read prior session outputs + running ECM/FIM register
2. Review equipment analysis, trend data, and SOOs for this system
3. Identify ALL ECMs (controls/sequence changes) and FIMs (hardware repairs/replacements)
4. Apply consolidation rules: merge into existing items or create new ones
5. Document findings in Finding Block Format blocks
6. Update running ECM/FIM register
7. Save structured output file

Running Artifacts:

• session-outputs/ecm-fim-register.md — updated after every session
• session-outputs/phase-2-<N>-<system>-output.md — per-system discovery output

Cross-System Interactions: Document interactions between systems as they emerge (e.g., upstream AHU issues affecting downstream terminal units). These inform priority assignment in Phase 4.

Phase 4: Quantification & Cost Estimation

4.1 — Savings Calculations:

• Quantify Table A ECM candidates in xlsx with working formulas (see ECM/FIM Calculation Tools below)
• Document methodology, assumptions, and confidence level for each calculation
• Flag verification items that would improve accuracy

4.2 — Consolidation Review & ROM Costs:

• Final review of ECM/FIM list against consolidation rules (catch any missed groupings)
• ROM cost estimates by category: BAS programming, mechanical contractor, capital, specialty
• Validate costs against known budgets

4.3 — Table A (Quantified ECM Savings):

• Populate savings table for calculable ECMs
• Headline number for executive summary

4.4 — Table B (Implementation Priority Matrix):

• All ECMs/FIMs organized by priority (CRITICAL / HIGH / MEDIUM / LOW)
• Impact categories: Energy / Comfort / Artifact Preservation / Equipment Life / Code Compliance
• ROM cost ranges and action owners

Phase 5: Report Assembly

Mapping Table: Create a three-layer cross-reference:

• Report final # -> Register global # -> Phase source file + Phase ID
• Assembly instructions for consolidated items (which source files to merge)

Report Structure (typical):

1. Executive Summary (headline savings, key findings, replacement scope overview if applicable)
2. Analysis Results (Table A + Table B)
3. Recommendation Details (brief per-ECM/FIM narratives)
4. Recommended SOOs (appendix or inline, depending on project)
5. RCx Scope of Work (Finding Block Format: Findings -> Modified SOO -> Affected Equipment)
6. Appendices (equipment schedules, trend charts, field report reference)

Narrative Sections (not in ECM/FIM list):

• Equipment being replaced: summary paragraph with owner-discretion framing
• Interim improvements: short-term fixes at owner's discretion pending replacement
• Delivered items: reference to appendix

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ECM/FIM Calculation Tools

Principle

All ECM/FIM savings calculations are developed in Excel workbooks with working formulas. Python scripts generate these workbooks using openpyxl. The xlsx skill MUST be invoked when creating or modifying these tools.

Tool Directory

.claude/skills/rcx-analysis-reporting/tools/
├── ecm-motor-savings.py          # Motor scheduling/interlock savings
├── ecm-economizer-savings.py     # Economizer displacement savings
├── ecm-simhtgclg-savings.py      # Simultaneous heating/cooling waste
├── _styles.py                    # Shared styling constants and helpers
└── README.md                     # Tool usage documentation

Each Tool Must

1. Accept inputs via CLI args (quick one-off) AND JSON config (reproducible)
2. Generate .xlsx with working Excel formulas (never hardcoded Python math results)
3. Place all assumptions on a dedicated Assumptions sheet with yellow-highlighted inputs
4. Use blue text for user inputs, black for formulas, green for cross-sheet refs
5. Flag verification items with red text warnings
6. Include a Validation Column beside each formula: Python-computed result (static) + check cell (=IF(ABS(excel-python)<0.01,"✓","MISMATCH")). This proves the Excel independently reproduces the Python math and catches formula reference errors.
7. Provide engineering methodology notes for each calculation section: explain the physical principle (e.g., fan affinity cube law, sensible heat equation, bin-hour method), not just formula shorthand. Target reader: an ME who will not see the Python.
8. Annotate every input cell with a source tag: nameplate, drawing reference, utility bill date, ASHRAE table, or "VERIFY — assumed value, confirm with [specific source]". Unverified assumptions in red font; confirmed values in black.

Invocation Pattern

# CLI args (quick)
py -3.12 tools/ecm-motor-savings.py --hp 5 --hours-saved 5040 --elec-rate 0.10 --output savings.xlsx

# JSON config (reproducible, multi-equipment)
py -3.12 tools/ecm-motor-savings.py --config project-inputs.json --output savings.xlsx

Tool Status

• ecm-motor-savings.py: BUILT — pump interlock, fan scheduling, any motor-hour-based ECM
• ecm-economizer-savings.py: BUILT — economizer displacement with monthly hour estimates
• ecm-simhtgclg-savings.py: BUILT — simultaneous heating/cooling with valve characteristic corrections
• _styles.py: BUILT — shared styling constants and helpers

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Critical Corrections

ECM/FIM List Consolidation — Do It Upfront, Not After Discovery

Establish consolidation rules at the START of the analysis process (Phase 2), not at the costing phase. Rules: same root cause -> one item, equipment being replaced -> narrative paragraph, sensor repairs -> group by trade, delivered items -> appendix reference. In one prior project, 47 items across 10 sessions had to be consolidated to 19 at Phase 4.2, creating unnecessary rework.

ECM/FIM Calculations Belong in Spreadsheets, Not Markdown

ECM and FIM savings calculations must be developed in Excel workbooks with working formulas — never as hardcoded numbers in markdown. Markdown narratives document logic and assumptions; the .xlsx with live formulas is the auditable, adjustable deliverable. Use the xlsx skill to generate workbooks via Python/openpyxl scripts.

Trend Data Diagnostics — State Evidence, Not Conclusions

When BAS trend data shows command-vs-status disagreement, do not conclude "equipment failure." The same trend signature could indicate hardware failure, a failed status sensor, or a BAS wiring/communication issue. State what the data shows, list all plausible causes, and prescribe a physical inspection. Compare against peer equipment on the same system.

Concise Recommendations Over Exhaustive Analysis

Provide the recommendation and a brief note that alternative X was considered but dismissed due to Y. Do NOT write multi-paragraph justifications for every dismissed option. Deliverables should read as confident recommendations, not design decision journals.

Document Tone — Never Blame Team Members

Frame deliverables positively — what the analysis provides, NOT what someone failed to deliver. Never throw the EoR or any team member under the bus. Do not include internal workflow sections in external deliverables.

Excel Must Independently Verify Python Calculations

Python analysis tools and Excel Calculations sheets compute energy savings via independent paths. Both must arrive at the same result. Include a Validation Column that displays the Python result beside each Excel formula with an agreement check. Methodology notes must explain engineering basis for a non-Python audience. All assumptions must cite their source or be flagged for field verification.

TAB vs Cx Responsibility Distinction

Test & Balance (TAB) establishes system setpoints through balancing work. Commissioning (Cx) verifies performance based on TAB's established values. Use "TAB" for setpoint determination, "commissioning" for sequence verification. Apply throughout all deliverables.

Best Practices

Reusable Calculation Tools via xlsx Skill

For recurring ECM/FIM calculation types, create individual Python scripts that generate .xlsx workbooks with working formulas. Each tool accepts project-specific variables via CLI args or JSON config. Store tools in rcx-analysis-reporting/tools/ for reuse across projects. Always invoke the xlsx skill when building or maintaining these tools.