The front door carries the burner and closes onto the furnace tube behind it — a 5.3 m² face at about 120 °C, bare. It also has to hinge open for burner service.
Figures are for one boiler. Surface temperatures from a real FLIR survey of a UK commercial boiler house; CAD surface areas uplifted ×1.4 for bolts and irregular geometry; ISO 12241 steady-state (50 mm core, ambient 28 °C, air movement 0.5 m/s).
Drag-free toggle. Visible in this view: front (burner) door — 5.3 m² at ~120 °C, with the burner mounting.3D model: Inzonex · equipment rights belong to the manufacturer
The front door is large, hot and movable — the three properties that make rigid insulation fail. It runs at 120 °C over a big flat face, so it is a real standing loss; but it swings open every time the burner is serviced, so anything hard-fixed gets damaged or removed.
A buttoned removable panel is made to the door and hinges with it: insulated when closed, out of the way when open. The burner mounting flange and sight port stay clear.
| Element (this view) | Temp °C | Area m² | Bare W | Insulated W | Surface °C | Cut |
|---|---|---|---|---|---|---|
| Front (burner) door | 120 | 5.32 | 7,973 | 416 | 34 | −95% |
| Front / burner door view, per boiler | 5.3 | 7,973 | 416 | ≤45 | −95% |
ISO 12241, 50 mm Inzonex modular core, ε(bare)=0.9, ε(jacket)=0.85, hconv at 0.5 m/s. Insulated figures are conservative steady-state.
The front door carries the burner and closes onto the furnace tube, so it runs hot across a 5.3 m² face. It hinges open for burner service, which is exactly why rigid insulation fails here — a buttoned removable panel insulates the door and opens with it.
Cover: Silicone shell + PAROC stone-wool core (50 mm) · touch-safe design target ≤45 °C (ISO 13732-1 guidance)
Every module here re-opens for access.
Every surface on this view is covered by an Inzonex modular removable panel: a PAROC stone-wool core (50 mm) in a silicone outer shell — or a more durable PTFE shell as an option. The form-fitting build unbuttons for access and refits after each maintenance cycle. The outer surface drops to a touch-safe ≤45 °C.
Industries that run this boiler
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Open calculator → CarbonEvery bare kilowatt is real fuel and real carbon. See the tonnes and the EU-ETS cost behind it.
Carbon hub → 3D modelRotate the Cochran model, toggle bare vs insulated, and jump to every other surveyed surface.
Open 3D model →On the surveyed Cochran the front (burner) door measured ~120 °C over a 5.3 m² face, bare — roughly 8 kW of standing loss.
Yes — a removable panel is shaped to the door and hinges with it, insulated when closed and clear of the burner mounting and sight port when open.
About 34 °C — below the 45 °C touch-safe threshold — a ~95% cut in loss.
Selected readings from this boiler survey. This surface is the marked point.
On the Cochran the front door is a single hinged plate carrying the burner: 5.32 m² at about 120 °C, one element group, 7,973 W bare. It swings clear of the furnace tube, so the module comes off the door before the door moves.
The front door carries the burner and closes the furnace. It is opened for tube ends, refractory and burner head, and it is hinged, so anything wrapped across the hinge line is cut the first time it swings.
Inzonex did not operate the burner or the door. What we measured is the outside of the door and the flange while the boiler was running: on the Cochran 120 °C over 5.32 m², 7,973 W; on the Bosch UL-S 96 °C over 2.33 m² plus a 146 °C flange, 4,310 W together.
| Survey | Cochran, front / burner door. FLIR S62 Pro, emissivity 0.90, reflected 25 °C, 3 m, full radiometric correction. Peak on this view 120 °C. |
| Geometry | Rebuilt in CAD from the surveyed machine. This view carries 1 element group(s) and sheds 8 kW bare. The ×1.4 factor is a geometry allowance for bolts, seams and irregular surface — it is not a measured area. |
| Calculation | ISO 12241 steady state. Heat loss is calculated from the measured surface temperature and the modelled area — it is not metered. Full method, basis and limits. |
| Largest single item | Front (burner) door, 8 kW on this view. |
On a working Cochran package boiler the rear end plate and the economizer behind it run at 126–130 °C — FLIR-measured, bare. Together they are the sin…Open the measured page
→/ 02From the rear quarter the live-steam fittings come into view — check and main stop valves, the safety valves, the rear manhole, steam flanges and sens…Open the measured page
→/ 03The feed and condensate side runs near 100 °C across the pump, isolation valves, return lines, strainer and blowdown — many small bare surfaces that q…Open the measured page
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