Nicotra Gebhardt DD / DDM Alternative — LONGWELL DDK / SDDK series

Looking for an alternative to Nicotra Gebhardt DD / DDM? LONGWELL's commercial centrifugal line mirrors the Nicotra naming 1:1 — DDK / SDDK series — with identical frame designation, dimensional interchangeability, belt-drive or factory EC-upgrade, AMCA-tested aerodynamics, at 40–55% lower landed cost and 15-day delivery vs 10–14 weeks ex-works Nicotra. This is the single highest-value naming-mirror battle in the commercial AHU segment.

Replaces: Nicotra Gebhardt DDM 9/9 – DDM 15/15 (direct-drive EC) Frame / size: frame 9/9 – 15/15 · Ø225–355 mm Family: Nicotra DD / DDM → LONGWELL DDK (naming mirror) Sample: 1–3 days
Replacing
Nicotra Gebhardt
DD / DDM
DD / DDM · Forward-curved direct-drive (EC available)
With
LONGWELL
DDK / SDDK series
1:1 frame mirror · belt or EC · 15-day delivery

Specification Comparison

SpecificationNicotra Gebhardt DD / DDMLONGWELL DDK / SDDK series
Fan typeForward-curved direct-drive (EC available)Forward-curved direct-drive (EC available)
Impeller / frameframe 9/9 – 15/15 · Ø225–355 mmframe 9/9 – 15/15 · Ø225–355 mm Drop-in
Airflow range2,500–9,000 m³/h2,500–9,000 m³/h
Static pressure (max)450–700 Pa450–700 Pa
Power classdirect-drive EC / IE motordirect-drive EC / IE motor
AMCA 210 static efficiency (peak)66%66%
Noise floor (Lw)74 dB(A)74 dB(A)
Voltage230 / 400 V · 380–480 V 3Φ230 / 400 V · 380–480 V 3Φ
Drive / motorDirect-drive EC / IE motorDirect-drive EC standard Match + EC option
CertificationsCE · UL · EAC · AMCACE · UL · cUL · TÜV · EAC · RoHS · REACH
Sample lead time4–10 weeks1–3 days
Series lead time (≤500 units)10–14 weeks15–30 days
Landed cost index (LONGWELL = 100)175–200100 (baseline)

Engineered match verified against Nicotra Gebhardt DDM 9/9 – DDM 15/15 (direct-drive EC) in LONGWELL's cross-brand model library (record: NAMING_MIRROR — DDK/SDDK225-I →). DDK/SDDK225-I → DDM 9/9; DDK/SDDK250-I → DDM 10/10; DDK/SDDK315-II → DDM 12/12; DDK/SDDK355-I → DDM 15/15.

Why Engineers Switch from DD / DDM to DDK / SDDK series

4–8× Faster Delivery

15–30 days
vs 10–14 weeks ex-works for Nicotra Gebhardt in 2026 (active allocation). Sample units 1–3 days from stock.

40–55% Lower Landed Cost

−40 to −55%
per unit at equivalent spec. On a multi-unit AHU / fan-grid program the CapEx delta scales fast.

Belt or EC-Upgrade Path

25–40%
fan-energy saving available via the factory EC-drive (-K) variant vs the standard belt-drive Nicotra arrangement.

Drop-In Compatibility Details

Frame & dimensional match

LONGWELL DDK / SDDK series carries the identical Ø225–355 mm frame designation as Nicotra DD / DDM — scroll dimensions, inlet cone, outlet flange, and shaft/bearing centres match 1:1, so it drops into the same AHU section, the same belt-guard, and the same pedestal without rework.

Drive & motor options

LONGWELL ships the DDK / SDDK series as direct-drive EC standard, matching the Nicotra DD / DDM direct-drive arrangement and adding 0–10 V / Modbus speed control for variable-volume AHU.

Performance match

The aerodynamic curve of LONGWELL DDK / SDDK series tracks the Nicotra DD / DDM within AMCA 210 test tolerance across the operating envelope (third-party tested). DDK/SDDK225-I → DDM 9/9; DDK/SDDK250-I → DDM 10/10; DDK/SDDK315-II → DDM 12/12; DDK/SDDK355-I → DDM 15/15. Performance is matched at the published duty point, with LONGWELL's documented cross-brand library backing the selection.

Typical Applications

The LONGWELL DDK / SDDK series is widely deployed across compact direct-drive AHU and rooftop / fan-coil units. Common application categories include:

  • Compact direct-drive AHU
  • Fan-coil & rooftop units
  • Space-constrained plant rooms

The DD/DDM direct-drive line removes the belt entirely; LONGWELL DDK/SDDK mirrors the frame and ships EC as standard.

FAQ

Is LONGWELL DDK / SDDK series dimensionally interchangeable with Nicotra DD / DDM?
Yes. LONGWELL mirrors the Nicotra commercial naming 1:1 — DDK / SDDK series carries the same Ø225–355 mm frame designation, scroll dimensions, inlet/outlet geometry and shaft centres, so it fits the same AHU section and pedestal. DDK/SDDK225-I → DDM 9/9; DDK/SDDK250-I → DDM 10/10; DDK/SDDK315-II → DDM 12/12; DDK/SDDK355-I → DDM 15/15.
Does LONGWELL offer an EC-upgrade for the DD / DDM?
Yes — the LONGWELL DDK/SDDK direct-drive line is EC as standard, giving 0–10 V/Modbus variable-volume control without a belt.
What's the 2026 lead-time and cost difference?
LONGWELL DDK / SDDK series ships in 15–30 days vs 10–14 weeks ex-works for Nicotra DD / DDM under allocation, and typically lands 40–55% below Nicotra ex-works pricing at equivalent spec. Samples ship in 1–3 days.
Why does LONGWELL use the same model naming as Nicotra?
LONGWELL's commercial centrifugal line was engineered to be a 1:1 functional and dimensional mirror of the Nicotra Gebhardt range, so specifiers can cross-reference by frame designation directly (AT, DD/DDK, RDH/RDH-R, RZR/RLM E, ADH). It removes re-selection effort — the LONGWELL part is the same size, same duty, same AHU section.
Can I get the full Nicotra-to-LONGWELL commercial cross-reference?
Yes — the complete AT / DD / RDH / RZR / ADH naming-mirror table is in the cross-reference, and the Commercial Blower Portfolio Pack covers the full line. Send the Nicotra model + duty point to sales@zjlongwell.com for a verified equivalent and sample.

Replace your DD / DDM in 5 days

Send a quick request — model + quantity + delivery address. Sample unit ships in 1–3 days for field validation. Series production at 15-day lead time after PO.

Request Sample View Full Cross-Reference Table
Official Product Page
Browse the full Commercial Centrifugal Fans & Blowers range on longwellfans.com — request a quote on DDK / SDDK series directly.
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Nicotra Gebhardt® is a trademark of its owner. LONGWELL is an independent manufacturer and is not affiliated with, endorsed by, or sponsored by Nicotra Gebhardt. This page is published as engineering reference based on public datasheets.