Bosch UL-S · package boiler ·Steam valves & piping

Bosch boiler steam valve heat loss

The steam take-off and stop valves sit at the boiler’s saturation temperature — the FLIR survey measured 190 °C, the hottest surface on the boiler, bare.

FLIR-measured surface temps CAD areas × 1.4 bolt/irregularity ISO 12241 · v = 0.5 m/s

Bare · up to 190 °C Insulated · ≤45 °C

Drag-free toggle. Visible in this view: steam take-off and stop valves — 190 °C, bare cast bodies.3D model: Inzonex · equipment rights belong to the manufacturer

Peak surface

190 °C

Bare, FLIR-measured

Largest loss

1.4 kW

Steam valves

This view, bare

1.4 kW

1 element group(s)

After insulation

≈95%

Surface drops to ≤45 °C

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).

What you are looking at

Bosch boiler steam valve heat loss

Valves are the surface insulation contractors skip most, because their cast shapes don’t suit rigid boxes — yet they run at the hottest temperature on the boiler, the saturated-steam 190 °C.

Per unit area a bare valve loses more than a flat plate at the same temperature. Two-part removable covers insulate the body and seats while leaving the stem and gland serviceable.

Element (this view)	Temp °C	Area m²	Bare W	Insulated W	Surface °C	Cut
Steam valves	190	0.45	1,430	70	36	−95%
Steam valves & piping, per boiler		0.45	1,430	70	≤45	−95%

ISO 12241, 50 mm Inzonex modular core, ε(bare)=0.9, ε(jacket)=0.85, h_conv at 0.5 m/s. Insulated figures are conservative steady-state, not best-case.

Element by element

Why each one is left bare — and how it gets insulated

Steam valves · 190 °C · 1.4 kW bare

The steam take-off and stop valves sit at the boiler’s saturation temperature, 190 °C — the hottest measured surface. Two-part removable covers insulate the bodies and cut ~95% of the loss, with the stems left exposed for service.

Geometry that re-opens for access is the core idea behind the Inzonex modular design.

Materials & standards

What the cover is — and what it meets

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.

ISO 12241 heat-loss methodISO 13732-1 ≤45 °C touch-safeEN 13501-1 reaction to fireASTM C680 heat-loss method

Industries that run this boiler

Brewery & beverageFood processingDairyChemical & petrochemicalPharmaceuticalPower & CHPOil & gas / refiningCommercial laundry

Take it further

From this surface to the number that matters

Calculator

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Heat loss → CO₂ → EU ETS

Every bare kilowatt is real fuel and real carbon. See the tonnes and the EU-ETS cost behind it.

Carbon hub → 3D model

See it on the boiler

Rotate the Bosch UL-S model, toggle bare vs insulated, and jump to every other surveyed surface.

Open 3D model →

FAQ

Quick answers

How hot are Bosch boiler steam valves?

The FLIR survey measured the steam valves at 190 °C bare — the hottest surface on the boiler.

Can steam valves be insulated?

Yes — with two-part removable covers shaped to the body. They cut ~95% of the loss yet pull off for inspection, with the stems left exposed.

How much does a bare steam valve lose?

On the surveyed Bosch the steam valves lost 1.43 kW bare, cut to 0.07 kW insulated — a 95% reduction.

More of this boiler

Other surveyed views

Every face of the Bosch UL-S model has its own measured surfaces. Explore them from the 3D hub.

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