File-backed graph · SQLite + notes + jsonl · Neo4j not running

Heat pump water heater research vault — overview (16–18 Aug 2026)

Southern Heat Pumps / Engineer: water heater · Lexington · quest only

Quest design a novel heat pump water heater for the US and Canada that uses AI to maximize efficiency.

Product research brief. Not a sales sheet. Figures are from vault.db after ingest A–D (16 Aug 2026). Disagreements are left standing. No Decision nodes. No CAD.

00

Vault size

Verified against vault.db. 55 works = 6 research reports + 9 scratches + 40 primary sources (including stubs). 289 claims, 28 concepts, 14 parts, 19 markets, 441 edges.

Node inventory

Counts as stored. Claims dominate because each work asserts load-bearing sentences.

Works by kind

6 research reports · 9 scratches · 40 primary sources, including stubs.

Edge mix

441 edges: 289 asserts, 51 about, 41 sourced_from, 26 applies_to, 25 cites, 9 disputes.

Ontology in use
NodePresentEdgeCount
Work55asserts289
Claim289about51
Concept28sourced_from41
Part14applies_to26
Market19cites25
Standard, Sourcein graphdisputes9
Assemblynone
Decisionnone

01–04

Four layers

The spine of the corpus. Wording below is the vault’s, not a paraphrase that would smooth tensions.

Layer 1

The job

A comfortable shower is 15–25 kW. No residential heat pump and no 30 A circuit can supply that live. The machine must store, burn gas, or the shower is worse.

DOE UEF test assigns daily volume from first-hour rating (10 / 38 / 55 / 84 gal), not from field measurement.

Conversion used in the third-pass: kW = gpm × ΔT(°F) × 0.1465

Layer 2

The world stock

Heaters are local machines.

US
glass-lined storage, gas and electric nearly even, HPWH still a small slice (190k shipments 2023).
Canada
SHEU 2019 — 12.4 M heaters, 10.8 M tanks, 34k HPWH quality M.
Japan
gas + Eco-cute (10 M cumulative shipments Mar 2025, not remaining stock).
England
combi.
Brazil
chuveiro or no heat (PPH P1: ~70% electric in 2005, ~40% electric / ~60% no-heat in 2019).
Solar thermal
SHWW 2025 544 GWth / 443 TWh; China dominates; thermosiphon in the rest of the south.
World-stock callouts that have counts

Not a ranking. Stock ≠ annual shipments ≠ cumulative shipments. Canada SHEU 2019 is quality M. Eco-cute 10 M is cumulative shipments to Mar 2025, not remaining stock. US 190k is 2023 HPWH shipments.

Same figures, with the metric attached
PlaceFigureWhat it isQuality flag
Canada12.4 Mheaters, SHEU 2019 stockquality M
Canada10.8 Mtanks, SHEU 2019 stockquality M
Japan10 MEco-cute cumulative shipments to Mar 2025not remaining stock
US190kHPWH shipments, 2023shipments, not stock
Canada34kHPWH, SHEU 2019 stockquality M

Layer 3

The clock

Night-charge regimes (Australia ripple, Japan 深夜電力, France HP/HC) are being inverted toward solar noon.

CTA-2045 / EcoPort is the North American port.

IEEFA: hot water ~¼ of Australian household electricity; AGL 140 MW via PLUS ES.

Layer 4

The incumbent stack

After 6 May 2029, common-sized US electric storage must meet heat-pump UEF.

FR 89 FR 37778: 17.6 quads, 332 Mt CO2, share 3% (2023) → ~61% (2030, TSL 2).

The volume machine is an A. O. Smith Juárez glass-lined tank, Highly-class China rotary, R-134a, 4.5 kW backup elements, Wise Ally / Computime controls, optional EcoPort.

Glass-lining furnace is the non-electronics CAPEX bottleneck.

05

Parts the graph tracks

Fourteen Part nodes. Country of origin unpublished unless a filing names it. co2-outdoor is Voltex X, not 2026 volume.

FCC 2BWHU1LD one work

Grant 23 Jul 2026, Murata LBEE5PA1LD-222, 2412–2462 MHz, 0.03589 W, Wi-Fi only, single modular. Host unpublished. Not proven inside current HPTS.

“1LD-Ayla / CYW43438 + STM” and Bluetooth are not in the exhibits. UseCARE 2025 still prints Wi-Fi+Bluetooth on the Control Assembly.

Product page says NEEA Tier 3; QPL says HPTS-50/66/80 Tier 4, EcoPort Yes, UEF 3.80 / 3.70 / 3.88.

Juárez ImportInfo bills

Highly 29, China WH 22, Computime 13, Time Engineering 12. Changfa ships evaporator and clip.

Do not claim USMCA origin; RVC unpublished.

06

Tensions left standing

Each pair is a disagreement or a quality break. Do not average. Do not pick a winner. The 9 disputes edges live here as readable pairs.

  1. NOPR 27 quads

    vs

    Federal Register 17.6 quads

  2. HPTS page “NEEA Tier 3”

    vs

    QPL Tier 4

  3. Table UEF 3.8 / prose 3.88

    vs

    QPL 3.80

  4. 2016 handbook heat-pump floor 45°F

    vs

    2024 handbook / UseCARE 37°F

  5. Reports “~95% of HP compressors”

    vs

    HPM “~90% of rotary manufacturing capacity”

  6. REN21 China 391.8 GWth

    vs

    SHWW 410.1 GWth

  7. Brazil viral 70% electric shower

    vs

    that figure is 2005, not 2019

  8. Eco-cute “close to 15%” stock phrase

    vs

    not found in extracted HPM pages

  9. 15–20 kg copper

    vs

    flagged as air-to-air space HP, not HPWH

  10. TSD Chapter 5 dollars never arrived (download stubs)

    vs

    $207.87 / $446.41 / $479.57 / $526.86 stay with the already-opened TSD in the reports

  11. South Africa GHS 2023/2024 are Incapsula stubs

    vs

    3.3% solar geyser unconfirmed

  12. Several ImportInfo supplier pages are login walls

    vs

    APCOM, Morita, Heatec, Thermalub, Water Products, Qiaoyun

07

Design implication

08

Stubs and holes

Unreadable on purpose

  • SA GHS
  • DOE TSD downloads
  • Murata datasheet
  • NEEA landing page
  • fcc.gov Access Denied PDFs
  • several ImportInfo logins

Empty

  • CAD
  • Assembly nodes
  • Decision nodes
  • Neo4j

Intended stack (not running as a graph): Neo4j backbone; Blender / FreeCAD / OpenSCAD for geometry. Until then the store is file-backed: vault.db, notes/, graph/*.jsonl.