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Energy Agent · Fault library

The faults that waste energy in commercial buildings, one page each.

Energy Agent runs 96 fault-detection rules over the meter and BAS data your building already produces. This library explains what each fault means, why it costs you money or comfort, and what to do about it.

Browse by familySee Energy Agent
96rules
8equipment families
16Guideline 36 conditions
17diagnostic rules

What a rule page gives you

  1. What it means. The physical situation the rule has found, in plain terms: which equipment, which condition, and over what kind of period.
  2. Why it matters. What the fault costs — energy, demand, comfort, equipment life — and why it tends to go unnoticed.
  3. What to do. Where to look first and the usual fixes, ordered from the cheapest and most common cause outward.

The sixteen AHU-FC rules are aligned with the fault conditions FC01–FC16 described in ASHRAE Guideline 36. The logic is expressed in Pelorus Engineering’s own engineering terms; Guideline 36 text is not reproduced here.

Tools

Start with the data you have

Three short tools that turn "what data do we have" into "what would Energy Agent find", before anyone signs anything.

3 minutes

Is your building ready for fault detection?

Answer a few questions about your meter and BAS points. See how many of the 96 rules can run today, the one point that unlocks the most, and get the summary by email.

Take the readiness quiz →Interactive

What your data unlocks

Flip the switches for the data you have and watch the 25 analyses in Energy Agent turn on, run with a caveat, or wait. The same gate the product runs.

Open the board →9 guides

How to get your data

Interval data from the utility, trend exports from Niagara, Metasys, Tracer, Desigo and EcoStruxure, schedules and bills. With CSV templates.

Read the guides →
Reading a rule page

How to read a rule

Every rule page has the same three sections, written for the person who has to act on it rather than the person who wrote the detector.

The pricing badge

Each rule carries a pricing badge. Physics-based rules use a rule-specific model of the wasted energy. Capacity-based rules combine the equipment’s capacity, its duty and the fault hours. Meter rules are priced directly from the excess the meter recorded. The method is stated on every finding in Energy Agent, never hidden.

Diagnostic rules claim no dollars

Diagnostic rules claim no dollars at all, by design. A biased sensor, an under-ventilated classroom or a boiler that cannot hold setpoint is still surfaced and ranked, but as a comfort, reliability or data-quality problem — never inflated into savings.

Faults cascade

When an upstream delivery problem explains a downstream symptom over most of the same hours, the symptom is folded into its cause so one root cause is not counted several times. The hidden dollars still appear on the cause.

A data-quality gate runs first

Before any rule runs, a data-quality gate checks the supplied trends — gaps, frozen channels, unit mismatches, timestamp problems — and decides which analyses the data can actually support. A rule that cannot be trusted on your data is not run.

What this library does not show

This library describes the faults, not the detectors. Thresholds, tolerances and timing windows are tuned per building inside Energy Agent and are not published here.

Families

Browse by equipment family

11 rules

Whole-building meter

What the utility meter alone can prove.

32 rules

Air-side AHU

Air handlers, including the Guideline 36 conditions.

7 rules

VAV / zone

Terminal boxes and the zones they serve.

10 rules

Zones & IAQ

Comfort, ventilation and humidity where people are.

18 rules

Central plant

Chillers, boilers, towers and pumps.

7 rules

Packaged RTU / DX

Packaged rooftop and split DX units.

6 rules

Heat pumps / VRF

Heat pumps and variable-refrigerant-flow systems.

5 rules

DOAS / ERV / exhaust

Dedicated outdoor air, energy recovery and exhaust.

Index

All 96 rules

Search by code, equipment or symptom, or narrow by family and pricing. Every rule links to its own page.

See these rules run on your building.

Send twelve months of interval data and a BAS trend export. Energy Agent returns a ranked list of what is wasting money, what each item is worth per year at your tariff, and what to do about it.

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