Ziehl-Abegg RH35C Alternative — LONGWELL LWBE3G-355-EC

Looking for an alternative for Ziehl-Abegg RH35C-6DK? The LONGWELL LWBE3G-355-EC is the dimensionally interchangeable equivalent — same mounting, same control protocol, AMCA 210/211 third-party-tested performance — at 40–55% lower landed cost with 15-day delivery vs 12–18 weeks ex-works Ziehl-Abegg. Widely deployed across Plenum AHU, data center RDHx, semiconductor FFU.

Replaces: Ziehl-Abegg RH35C-6DK Diameter: Ø355 mm Family: RH series → LONGWELL LWBE3G / LWAE3G / LWHV Sample: 1–3 days

Replacing

Ziehl-Abegg
RH35C

RH series · EC backward-curved centrifugal plug fan · Ø355 mm

→

With

LONGWELL
LWBE3G-355-EC

Drop-in dimensional match · Same control · 15-day delivery

Specification Comparison

Specification	Ziehl-Abegg RH35C	LONGWELL LWBE3G-355-EC
Fan type	EC backward-curved centrifugal plug fan	EC backward-curved centrifugal plug fan
Impeller diameter	Ø355 mm	Ø355 mm Drop-in
Airflow range	800–4,200 m³/h	800–4,200 m³/h
Static pressure (max)	1200 Pa	1200 Pa
Motor power (max)	950 W	950 W
Wire-to-air η peak (AMCA 210)	90%	87%
Noise floor (Lw)	68 dB(A)	71 dB(A)
Voltage	380–480 V 3Φ	380–480 V 3Φ
Control input	0–10 V / PWM / Modbus / EC-Control	0–10 V / PWM / Modbus RTU / Modbus TCP Compatible
IP rating	IP54 / IP55	IP54 std · IP55 / IP67 option
Certifications	CE · UL · VDE · EAC	CE · UL · cUL · TÜV · ATEX · VDE · EAC · RoHS · REACH
Sample lead time	4–10 weeks	1–3 days
Series lead time (≤500 units)	12–18 weeks	15–30 days
Landed cost index (LONGWELL = 100)	175–200	100 (baseline)

Why Engineers Switch from RH35C to LWBE3G-355-EC

4–8× Faster Delivery

15–30 days

vs 12–18 weeks ex-works for Ziehl-Abegg in 2026 (active allocation). Sample units 1–3 days from stock vs 4–10 weeks.

40–55% Lower Landed Cost

−€600 to −€2,400

per unit at equivalent spec, depending on size and quantity. On a 50-unit FanGrid retrofit, typical CapEx delta is €30k–€120k.

True Drop-In Compatibility

±0.5 mm

mounting hole tolerance + identical control protocol. Installation time same as same-brand replacement.

Drop-In Compatibility Details

Mechanical match

The LONGWELL LWBE3G-355-EC matches the Ziehl-Abegg RH35C mounting pattern (M-mount, ISO 9001 plenum-fan footprint) within ±0.5 mm tolerance. Inlet ring diameter, motor shaft height, and electrical termination box position are identical. Drop-in retrofit requires no AHU rework, no plate modification, and no plenum hole resizing.

Electrical & control match

The LWBE3G-355-EC accepts the same 0–10 V analog speed reference, PWM (1 kHz), and Modbus RTU (RS485) control signals as Ziehl-Abegg RH35C. Default Modbus register map is compatible with the Ziehl-Abegg ecosystem; LONGWELL provides a free Modbus map cross-reference for BMS integration. Ziehl-Abegg-specific proprietary protocols (EC-Control bus) are bridged via a free MODBUS gateway available from LONGWELL Engineering — no BMS reprogramming required.

Performance match

The PQ curve of LONGWELL LWBE3G-355-EC sits within 2–3% of the Ziehl-Abegg RH35C curve across the full operating envelope (verified by third-party AMCA 210/211 testing at TÜV and Intertek labs). Wire-to-air efficiency at BEP is 87% vs 90% for Ziehl-Abegg (3 pp delta at peak). In typical part-load HVAC duty, the gap narrows to within 1 pp.

Typical Applications

The LWBE3G-355-EC is widely deployed across Plenum AHU, data center RDHx, semiconductor FFU. Common application categories include:

Plenum AHU
Heat pump
L2A cooling
FFU

Particularly suited for L2A data center modules and heat pump fan coil sections.

FAQ

Is LONGWELL LWBE3G-355-EC a true drop-in replacement for Ziehl-Abegg RH35C?

Yes. The LWBE3G-355-EC matches the RH35C dimensionally (mounting hole pattern, inlet ring diameter, motor shaft height) within ±0.5 mm tolerance, accepts the same 0–10 V analog / PWM / Modbus RTU control signals, and operates from the same 380–480 V 3Φ supply. Installation time and AHU integration are identical to a same-brand replacement.

How does LWBE3G-355-EC compare on efficiency to RH35C?

Ziehl-Abegg RH35C delivers 90% peak wire-to-air efficiency at BEP. LONGWELL LWBE3G-355-EC measures 87% in AMCA 210/211 third-party testing — a 3 pp difference at peak. In typical part-load HVAC duty (30–80% of design airflow), the gap narrows to within 1 pp because both platforms hold flat η curves across their operating range.

What’s the 2026 lead time difference?

As of May 2026: Ziehl-Abegg RH35C requires 12–18 weeks ex-works due to ongoing allocation. LONGWELL LWBE3G-355-EC ships in 15–30 days for orders up to 500 units and 6–10 weeks for 1,000+ unit OEM programs. Sample units ship in 1–3 days from stocked Ø355 mm inventory.

What’s the cost delta?

At equivalent specification (same Ø, same airflow/Pa, same IP, same control), LONGWELL LWBE3G-355-EC typically lands at 40–55% below Ziehl-Abegg RH35C ex-works pricing. Final pricing depends on quantity, voltage, IP rating, and control protocol options.

What applications is LWBE3G-355-EC typically used for?

LWBE3G-355-EC is widely deployed across Plenum AHU, data center RDHx, semiconductor FFU. Particularly suited for L2A data center modules and heat pump fan coil sections.

Replace your RH35C 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 Backward-Curved Centrifugal EC Fans range on longwellfans.com — request a quote on LWBE3G-355-EC directly.

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Ziehl-Abegg® is a registered trademark of Ziehl-Abegg GmbH. This page is published by LONGWELL, an independent manufacturer and is not affiliated with, endorsed by, or sponsored by Ziehl-Abegg. All performance data sourced from publicly available datasheets.