BOILERS / METHOD / COMPARISONS
Boiler heat-loss totals: component scope and CAD allowances
Based on the published Boilers surveys and model outputs. Read the source scope alongside each comparison.
Published inputs and what they mean
A view, a case study and a whole-machine model can have different component inventories. Compare like-for-like rows before comparing their totals. Overlapping views must not be added twice.
| Published component group | Area m² | Bare W | Panelled W |
|---|---|---|---|
| End plate and economiser | 16.63 | 27,390 | 1,425 |
| Rear steam fittings | 3.15 | 9,095 | 458 |
| Feedwater including blowdown flanges | 4.74 | 6,214 | 323 |
Reconcile the Cochran total before combining studies
Re-running the source calculation for all 28 Cochran components gives 50.672 kW bare and 2.622 kW panelled after rounding each row. The legacy machine summary is 49.750 and 2.580 kW. The differences are 0.922 and 0.042 kW. Both describe 28 components: a difference in inventory has not been established, and the discrepancy remains unresolved. Use the individually listed component values for the component comparisons here; do not treat either summary as an independently validated total.
Published machine summaries
| Machine summary | Bare kW | Panelled kW | Scope |
|---|---|---|---|
| Cochran | 49.750 | 2.580 | Legacy summary; reconciliation above |
| Bosch UL-S | 23.434 | 1.203 | Published whole-machine model |
| Bosch ZFR | 53.390 | 3.990 | Published whole-machine model |
These are the existing model totals used by the Boilers section. They are not sums of only the selected surfaces in the comparison above. In particular, the Bosch front-door page covers 4.310 kW bare, not the 23.434 kW whole-machine total. A component-by-component reconciliation is required before combining inventories from different presentations; no balancing component is invented here.
What the area allowance represents
| Surface | Base area implied by rounded published value, m² | Allowance | Published area m² |
|---|---|---|---|
| Cochran end plate | 3.800 | ×1.4 | 5.32 |
| Cochran economiser | 8.079 | ×1.4 | 11.31 |
| Bosch UL-S door | 1.664 | ×1.4 | 2.33 |
The implied base is published area ÷ 1.4; rounding means it is not a replacement for the original CAD export. The factor is a geometry allowance for bolts, nuts, seams and irregular surfaces. It is not an inventory of individually measured bolt heads, nuts or exposed studs. The separate Bosch case uses +12%; its scope and basis must be retained rather than changed to match a different page.
For exact geometry, record exposed hardware and contact surfaces explicitly and prevent double counting. A change of allowance alone is not a measured improvement in the equipment.
Sources: Cochran model, Bosch UL-S model, Bosch ZFR model, Bosch case and methodology and limitations.