The rule
HVAC marketing runs on recycled statistics. A number gets quoted, the citation falls off, and a decade later it appears on a thousand contractor websites attached to claims its authors never made. We sell monitoring, which means our whole product is trust in numbers. So we hold every published figure to a sourcing test: name the agency, name the study, or show the math. Every statistic on this site carries its source inline or in a Sources section at the bottom of the page.
The savings floor, built from cited parts
When we say monitoring can recover roughly 15% of what a neglected unit spends on energy, that floor is assembled from three documented component figures, each about the HVAC equipment itself, not the whole building:
| Fault or fix | Energy impact | Source |
|---|---|---|
| Clogged air filter | 5–15% | U.S. Department of Energy, energy.gov |
| Improper refrigerant charge | 10–20% | Downey & Proctor 2002, ACEEE (13,000-unit field study) |
| Rooftop-unit control retrofits (field-measured) | 5–15% | PNNL-22656, Pacific Northwest National Laboratory |
A neglected unit usually carries more than one of these faults at once. Stack a dirty filter on a low charge and double-digit recovery on that unit's own energy is the expectation, not the ceiling. That is why we treat ~15% of the HVAC line as a conservative floor, and 30% as the multi-fault upside on a badly neglected unit. The worked examples on the homepage use a 20% recovery scenario: the top of the refrigerant-charge range alone (10 to 20%, Downey & Proctor), and well under what DOE-published field programs recovered when charge and airflow were corrected together (a 38% average gain in delivered capacity across more than 1,300 tune-ups in the Arkansas CoolSaver program, reported in DOE's Building America measure guideline). The claim is always scoped to the HVAC line, the energy the equipment itself uses, never to the building's total bill.
The famous number we refuse to quote
The most-cited statistic in this industry says poorly maintained and improperly controlled equipment wastes 15 to 30% of energy. The primary source is Katipamula & Brambley (2005), a peer-reviewed review written at Pacific Northwest National Laboratory. It is a real, well-founded figure. It is also about energy used in commercial buildings, meaning whole-building energy, not HVAC energy. Restating it as “15 to 30% of your HVAC energy” changes what the authors measured, and most of the industry does exactly that. We don't. When we cite Katipamula & Brambley, we cite it as a whole-building commercial figure. Our own 15 to 30% HVAC-line range is a different construction: the component-fault stack in the table above, each part separately cited.
Shown math counts as a source
Some numbers have no agency to cite because they are our own arithmetic, so we show it. Our anchor operating figure, about $286 per ton per year of cooling OpEx in NYC, is tons times roughly 1.0 kW per ton, times about 1,600 equivalent full-load hours, times a deliberately conservative $0.18 per kWh marginal rate. Every input is on the page, every assumption is flagged, and the all-in commercial rate ($0.24 to $0.30 per kWh) that would raise the figure is stated next to it. The full derivation is in What HVAC really costs a NYC building per year. When we quote a floor, we say it is a floor.
What we claim about the technology
The detection engine is statistical baselining: per-unit, per outdoor-temperature-band mean and variance, with deviation scoring against the matching band. It is deliberately explainable, and you or your engineer can audit the math behind any alert. We do not claim deep learning, and we do not quote failure-prediction accuracy we haven't earned on a large deployed fleet. The mechanics are on How it works.
How pricing follows from the sourcing
Because the savings floor is built from cited figures, we can price against it honestly: each subscription is priced below the energy it is expected to save, by a wide margin in the worked scenarios, so the customer keeps more than half of what AirPulse finds. Longer equipment life, avoided emergencies, demand-charge relief, and LL97 headroom are upside on top, never counted in the pricing test. And the caveat ships with every claim: actual savings depend on your equipment, runtime, and utility rate.
Sources
- U.S. Department of Energy, Air Conditioner Maintenance (clogged filter: 5 to 15% of an AC's energy use): energy.gov/energysaver/air-conditioner-maintenance
- Downey, T. & Proctor, J. (2002), “What Can 13,000 Air Conditioners Tell Us?”, ACEEE Summer Study (improper refrigerant charge: 10 to 20% of unit efficiency): aceee.org/files/proceedings/2002/data/papers/SS02_Panel1_Paper05.pdf
- Pacific Northwest National Laboratory, PNNL-22656 (rooftop-unit control retrofits recovered 5 to 15% of building HVAC energy in the field).
- U.S. Department of Energy, Building America Program, “Measure Guideline: Air Conditioner Diagnostics, Maintenance, and Replacement” (field fault prevalence; 38% average delivered-capacity gain from correcting charge and airflow, Kuonen 2011): www1.eere.energy.gov/buildings/publications/pdfs/building_america/measure_guide_air_cond_diagnostics.pdf
- Katipamula, S. & Brambley, M.R. (2005), “Methods for Fault Detection, Diagnostics, and Prognostics for Building Systems, Part I,” HVAC&R Research 11(1), whole-building commercial figure: osti.gov/biblio/15011268
- U.S. Energy Information Administration, CBECS 2018 (commercial electricity end uses): eia.gov/tools/faqs/faq.php?id=1174