The Elmhurst Summary §15.1 lodges "Cylinder Size: Value known" with the
measured volume in the "Cylinder Volume (l)" line — the Summary-path
equivalent of the gov-API "Exact" descriptor. The mapper had no entry for
"Value known" so `_elmhurst_cylinder_size_code` raised UnmappedElmhurstLabel,
and even once mapped the measured volume was never threaded through, so the
cascade dropped the cylinder storage loss (~468 kWh/yr) from (219) water
heating on every measured-volume-cylinder Summary.
Per RdSAP 10 §10.5 Table 28 (p.55) a measured cylinder volume is used
directly. Map "Value known" → cascade code 6 (Exact) and thread the §15.1
"Cylinder Volume (l)" value into SapHeating.cylinder_volume_measured_l, which
`_cylinder_volume_l_from_code` (cert_to_inputs.py:5281) already reads for
code 6 — mirroring the gov-API path (mapper.py:1575/1885).
Pins simulated case 39 (P960-0001-001431): an age-A mid-terrace on direct-
acting electric room heaters (SAP code 691, cat 10, control 2602) with
electric-immersion DHW off a 117 L "Value known" cylinder. The full
extractor→mapper→calculator cascade now reproduces the worksheet's SAP-rating
block EXACTLY — SAP value 36.6365 (band F) and (272) CO2 2056.0731 kg/yr,
with (219) water heating 2637.5049 and (255) total energy cost 1802.0039.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The Elmhurst §15.1 "Insulated: No Insulation" label was lodged but absent
from `_ELMHURST_CYLINDER_INSULATION_LABEL_TO_SAP10`, so
`_elmhurst_cylinder_insulation_code` raised UnmappedElmhurstLabel — blocking
the parse of every Solar PV example cert (the solar `before` lodges "No
Insulation"). An uninsulated cylinder has no insulation *type*, so per the
no-misleading-insulation convention it maps to `cylinder_insulation_type =
None` rather than naming a material; the lodged 0 mm thickness carries the
storage-loss signal the SAP 10.2 Table 2 dispatch needs.
Slice 1 of the Solar PV Recommendation Generator (ADR-0026).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Slice 3a. The inverse of Epc.from_sap_score: the minimum SAP rating in a
band (C → 69, B → 81, …), used as the Optimiser's repair target for an
INCREASING_EPC goal (goal_value "C" → target SAP 69). Keeps the
band-target derivation in the domain rather than re-coupling to
backend.app.utils.epc_to_sap_lower_bound. 8 tests incl. round-trip
through from_sap_score; pyright strict clean.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
