The Roaster Desk

By Kai Nakamura · Production roaster & equipment editor · Updated 2026-09-17

Loring S15 Kestrel vs Diedrich IR-12

Recirculation gas efficiency vs IR drum familiarity

→ Loring S15 Kestrel

Loring wins on gas bill and emissions — but only if your permit timeline survives a 28-week lead.

Capital outlay: TrailsEmissions / gas use: WinnerHourly throughput: Winner
Lowest street price → DiedrichFaster batches → LoringLowest exhaust VOC → Loring recirculationIR radiant profile → Diedrich drum physics

Also searched: diedrich ir-12 vs loring s15 kestrel

Decision picker

Can you wait 28+ weeks from deposit?
What is your monthly gas budget priority?
Does your AHJ require afterburner certification?

Specification matrix

Batch capacity

Loring

15 kg

Diedrich

12 kg

Heat source

Loring

350,000 BTU/h gas

Diedrich

400,000 BTU/h gas

Drum / chamber

Loring

Single-wall steel

Diedrich

Double-wall IR drum

Batch time (typical)

Loring

12 min

Diedrich

14 min

Throughput (modelled)

Loring

56.3 kg/h

Diedrich

40 kg/h

Street price band

Loring

$185,000 USD

Diedrich

$95,000 USD

Exhaust

Loring

800 CFM

Diedrich

900 CFM

Lead time

Loring

28 wks — confirm with dealer

Diedrich

16 wks — confirm with dealer

Automation

Loring

Smart Roast PLC

Diedrich

IR control panel

Service hub

Loring

USA

Diedrich

USA
Airflow ctrlThermal stab.Drum speedAutomationCapex value
KestrelIR-12

Qualitative scores — verify against your roast program

Why this split

Loring recirculation cuts exhaust heat — Diedrich IR drum is the platform your tech already knows how to fix.

The split is capex vs operating cost, not cup quality. Both hit production specs when sized correctly.

Airflow path through a commercial drum roaster from burner to cyclone
Typical drum roaster airflow: burner → drum → cyclone chaff collector

Deep dives

Recirculation vs open exhaust

Loring S15 Kestrel recirculates hot gas — exhaust temperature drops and afterburner load shrinks.

Open-drum platforms vent more heat per batch. Model your gas meter at 50% and 75% charge before signing.

Verify with vendor

  • Request OEM combustion efficiency curve
  • Confirm AHJ afterburner requirement for your address
IR radiant heat transfer

Diedrich IR drums radiate through a double-wall — different first-crack timing than convection.

Operators switching from Probat or Giesen need 15–20 calibration batches, not a copied profile.

  • Log development time ratio across 3 charge weights
  • Compare ground colour at same end temp
What to verify with your dealer

Neither OEM publishes binding street prices — quotes move with queue and freight.

Verify with vendor

  • Confirm Loring S15 Kestrel lead time and freight to your dock
  • Confirm Diedrich IR-12 install kit and probe package included
  • Ask for three references at similar elevation and batch size

Side-by-side

Loring strengths & gaps

  • Low NOx afterburner standard
  • 35% gas savings vs conventional
  • Premium price

Diedrich strengths & gaps

  • Infrared precision
  • Strong US service network
  • Higher gas consumption vs Loring

FAQ

Looking for diedrich ir-12 vs loring s15 kestrel?
Same comparison — Loring S15 Kestrel is listed first by convention. Verdict and spec matrix are identical either way.
What throughput can I expect?
Modelled: 56.3 kg/h (Loring S15 Kestrel) vs 40 kg/h (Diedrich IR-12) including a 4-minute charge/cool cycle.
What street price should I budget?
Loring S15 Kestrel: $185,000 USD (As quoted Q1 2026, US install). Diedrich IR-12: $95,000 USD (As quoted Q1 2026, ex-install). Request refreshed quotes — neither includes install.
Which supports Cropster logging?
Loring S15 Kestrel: Yes with RT bridge — confirm with dealer. Diedrich IR-12: Yes with RT bridge — confirm with dealer.

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