mirror of
https://github.com/Hestia-Homes/Model.git
synced 2026-06-08 11:17:27 +00:00
3f68ec1f0d
SAP 10.2 Table 4f (PDF p.174) "Electricity for fans, pumps and other
auxiliary uses" row:
Liquid fuel boiler — flue fan and fuel pump 100 kWh/yr c) d)
Note c): "Applies to all liquid fuel boilers that provide main heating,
but not if boiler provides hot water only. Where there are two main
heating systems include two figures from this table."
Pre-slice the cascade's `_table_4f_additive_components` only wired:
- (230a) MEV / MVHR
- (230e) Main 2 gas-boiler flue fan (45 kWh)
- (230g) Solar HW pump
The liquid-fuel sibling row was missing — oil 1 worksheet (230d) and
oil pcdb 3 worksheet (230d) both lodge 100 kWh/yr "oil boiler pump"
that the cascade was silently skipping.
Implementation:
- Add `_LIQUID_FUEL_CODES = frozenset({4, 71, 73, 75, 76})` and new
`is_liquid_fuel_code(fuel_code)` helper in
`domain/sap10_calculator/tables/table_32.py`. Mirror of
`is_electric_fuel_code` — routes through `_to_table_32_code`
normalisation so Elmhurst-derived Table 32 codes (e.g. code 23
= bulk wood pellets, solid) don't collide with API enum codes
(where 23 = B30D community).
- Extend `_table_4f_additive_components` to add 100 kWh for Main 1
when `is_liquid_fuel_code(main.main_fuel_type)` returns True
(`isinstance(int)` guard for the `Union[int, str]` field). Mirror
the same gate for Main 2 per Note c) "Where there are two main
heating systems include two figures".
- LPG is GAS (Table 4b/4f convention, Ecodesign classification) —
`_LIQUID_FUEL_CODES` deliberately excludes 2/3/5/9 LPG codes.
Cascade impact across heating-systems corpus:
| Variant | SAP Δ | Cost Δ | PE Δ |
|-----------|-------------|-------------|-------------|
| oil 1 | +1.18→+0.60 | -£27→-£14 | -276→-124 |
| oil pcdb 1| +0.42→-0.15 | -£10→+£3.4 | -84→+67 |
| oil pcdb 2| +0.42→-0.15 | -£10→+£3.4 | -84→+67 |
| oil pcdb 3| +1.16→+0.59 | -£27→-£14 | -271→-120 |
| pcdb 1 | +0.57→-0.03 | -£13→+£0.6 | -109→+42 |
Cohort closures: pcdb 1 EXACT (-0.03), oil pcdb 1/2 closed to -0.15.
Golden fixtures impact:
- cert 0240 (dual-main oil combi 130): SAP integer 73→72 (resid
+0→-1), PE +1.02→+2.52, CO2 +0.11→+0.14. Dual-main certs add
2 × 100 = 200 kWh aux per Note c). Cert's published SAP 73
suggests the dual-main Q_space split (main_heating_fraction)
may also need wiring — slice candidate.
- cert 0390 (Firebird PCDF 9005 oil combi): PE -28.50→-28.08
(CLOSER to zero), CO2 -2.75→-2.73 (CLOSER to zero), SAP +7
unchanged.
Test:
test_sap_table_4f_liquid_fuel_boiler_flue_fan_and_fuel_pump_adds_
100_kwh — asserts oil pcdb 3 inputs.pumps_fans_kwh_per_yr ≥ 230
(130 base + 100 liquid fuel boiler aux).
Extended handover suite: 891 pass, 0 fail. Pyright net-zero (44=44).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
|
||
|---|---|---|
| .. | ||
| addresses | ||
| data_transformation | ||
| epc | ||
| sap10_calculator | ||
| sap10_ml | ||
| tasks | ||
| postcode.py | ||