The heat-network mirror of keep_existing_off_peak_meter: the override's
2313 default applies only when the replaced system's control is
cross-family (stale); an observed community control survives.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Per-axis choice (decided with Khalim): the kit axis concedes to the
evidence (community schemes skew modern; lodged community certs are
overwhelmingly thermostatted, none lodge 2301), the charging axis stays
flat-rate — usage-linked billing is scheme paperwork an override
cannot see.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
421 slab -> Other storage heaters (0.00); 422/423 integrated -> 0.20;
424/425 screed/timber -> 0.90/0.50 — per the Grid 1 row labels that name
the codes (PDF p.184). Closes the None all-low-rate fallback that
over-credited 7-hour-metered underfloor dwellings.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
ADR-0048's intended end-state (#1444 Part C): every mapped archetype now
resolves confident companions, so an incomplete set can only mean a new
archetype landed without choosing them — fail loudly at overlay time.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The last real archetype on the companion-gap log; the log test now
simulates a future incomplete archetype (warm-air heat pump, Group 5
control deliberately unmapped).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
_u_brick_thin_wall_age_a_to_e's `<= 280` check put an uninsulated solid-
brick wall of exactly 280mm in the "200 to 280mm -> 1.7" row; RdSAP 10
§5.7 Table 13 (spec PDF p.41) shares 280 as an unlabelled edge between
that row and "280 to 420mm -> 1.4", so the table text alone doesn't say
which row owns it.
Found by building cert 100031768368 (280mm exactly, band C) in Elmhurst
and comparing every worksheet line to the calculator: volume/ACH/floor/
doors matched exactly, but the wall didn't (1.70 vs Elmhurst's 1.40)
despite an identical input crosswalk. Initially reverted a first attempt
at this fix when it appeared to regress an already-pinned cert
(217091901, band A, also nominally 280mm, previously "confirmed" at
U=1.70) — but that cert's build script never actually set a wall
thickness field, so its shared Elmhurst assessment had silently
inherited a stale 260mm from an earlier build. Fixed that build script
and rebuilt with the correct 280mm entry: Elmhurst's worksheet now also
gives U=1.40, matching 100031768368 and confirming the fix rather than
contradicting it.
Both certs move to (near-)exact lodged matches: 100031768368 59.12 ->
61.21 (lodged 61, within 0.5); 217091901 60.82 -> 61.59 (lodged 62,
exact). Corpus gauge 77.8% -> 78.6% within-0.5, MAE 0.636 -> 0.627 (14
corpus certs lodge exactly 280mm solid brick). TDD'd, 46 pins + full
suite green (2310 passed).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Sizing selects the aroTHERM plus rung nearest PSR ~0.8 (0.8 x design heat
loss) — the Appendix-N efficiency peak, reproducing the pump a real
installer fits — rather than the MCS PSR>=1.0 capacity target, which
oversizes. Validated against the relodged Elmhurst ASHP cert (delta 0
held at the 5 kW Vaillant); the two self-snapshot pins re-pin to their
correctly-sized larger pumps, and the orchestrator/harness thread the
calculator's design heat loss so production sizes to the dwelling. Manual
SapResult test stubs carry the new design_heat_loss_kw field.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
_ashp_option threads its sized design heat loss into ashp_cost_inputs so
the cost band and the pump's efficiency record share one figure — a leaky
dwelling's larger pump is priced on the matching band.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
_ashp_option now selects the aroTHERM plus PCDB record matching the
threaded design heat loss (floor-area proxy fallback), so the overlay's
efficiency anchor is sized to the dwelling instead of a fixed 5 kW unit.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
design_heat_loss_kw = annual-average HLC x 24.2 K (SAP design temperature
difference) / 1000, the quantity Appendix N's PSR divides a heat pump's
rated output by — surfaced so the ASHP recommendation can size the pump.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The sizing ladder (Vaillant aroTHERM plus 3.5-12 kW PCDB records) picks
the smallest rung whose rated output meets the design heat loss, so SAP
10.2 Appendix N reads the heat-pump efficiency near its PSR peak instead
of collapsing on an undersized fixed unit.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
A system-replacing override whose category or control is not yet mapped
now logs an error naming the archetype and code, so the incomplete
companion set (which otherwise silently inherits the replaced system's
value) is visible for review — log-and-continue, matching flag_fuel_mismatch.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Control 2601 (SAP Table 4e Group 6 room-heater, +0.3 C conservative
default) now overlaid for electric room heaters, matching the gas/oil/
solid siblings, so a replaced storage heater's manual charge control
2401 (+0.7 C) no longer survives and over-warms the modelled dwelling.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
_has_suspended_timber_floor_per_spec only read the Main bp's per-part
floor_construction_type lodgement; the gov-API mapper frequently leaves
that None even when the global epc.floors[].description carries an
explicit "Suspended, ..." observation. _main_floor_u_value already fell
back to this joined description for the U-value calc — the infiltration
rule did not, so a genuinely suspended-timber floor silently entered
(12)=0 instead of 0.2 unsealed. Extracted the shared
_effective_floor_description helper and added a tri-state resolver
(explicit lodgement -> description, excluding "not timber" -> Table 19
footnote-1 age-A/B default) so both paths agree.
Cert 100061275133 (Elmhurst-validated build, PR #1439 handoff): engine
77.24 -> 76.33, now an exact match to lodged (76). Corpus gauge 77.7% ->
77.8% within-0.5, MAE 0.637 -> 0.636; floors ratcheted.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
