IP55 Axial Fan for Cold Storage Retrofit: 400mm Case Study

What the cold chain operator needed

A cold chain facility operator needed eight replacement fans for its cold storage evaporators, and an IP55 axial fan was the only sensible answer. The existing units were failing. Usefully, the evidence arrived as a single photograph of a WEIGUANG YWF4E-400B motor nameplate.

That photograph gave us everything. Namely a 250W power target, a 230V 60Hz supply, and a 400mm frame the replacement had to drop straight into.

The environment set the harder requirements.

• IP55 as a minimum, since a defrost cycle soaks everything nearby in condensation.
• Blowing airflow, pushing air through the evaporator coil rather than pulling over the motor.
• An integrated guard, because the fans sit exactly where people work.
• A drop-in fit for the existing 400mm class, without bracket changes.
• Compliance with general appliance safety standards such as EN 60335-1.

Eight units is a small order. Even so, it is exactly the kind of order that gets refused elsewhere. Evidently the customer had already found that out.

Building the IP55 axial fan variant

Basically, this was a light change to our standard 400mm AC axial platform. Three things had to change. One thing, usefully, did not.

Why EC was not on the table

An EC motor gives efficiency and speed control. However, the customer wanted eight fixed-speed replacements for simple AC fans, so neither benefit applies. Adding EC would only have added cost and control complexity to a straight swap.

Getting to IP55

Initially, the standard model was not sealed well enough. Reaching IP55 on the LWAA4E400B-5MEB-02-00 therefore meant upgrading the motor sealing, fitting a sealed cable gland, and protecting the windings against moisture ingress.

That last point is the one that matters in a freezer. A room cycling below zero and then defrosting drives moisture into any gap it can find. Once water reaches a winding, the fan is finished. Consequently the customer specified the rating rather than leaving it to us.

Blowing rather than suction

Similarly, the B variant met the requirement for a blowing configuration. It uses a different impeller and motor mounting orientation to push air forward, unlike the standard S suction models. On an evaporator you want air driven through the coil, so B is clearly the correct choice.

A small performance gain

Here the original motor was 250W. Our engineers specified 260W instead. Paired with our impeller design, that yields 4017 m3/h. The customer therefore gets better circulation than the failing units delivered, without any change to the mounting or the supply.

Finally, the certified operating range of -30C to +60C covered the application as it stood. No further modification was needed.

Technical Specifications

The approved figures are below. The protection type and the minimum ambient temperature are the two rows that actually decided this specification.

Technical Documentation

Meanwhile the technical data sheet provides full performance specifications, dimensional drawings, and wiring diagrams for the approved LWAA4E400B-5MEB-02-00 model.
View Technical Datasheet LWAA4E400B-5MEB-02-00 (PDF)

A customer-supplied image showing the nameplate of the original, failing fan motor, establishing the baseline electrical and performance parameters for the replacement.

Here the drawing from the datasheet details the key dimensions of the fan, including the 400mm impeller diameter and 90mm installation depth.

Why an eight-unit order was worth engineering

An eight-unit order is where a lot of suppliers stop returning calls. In this case, four things made it straightforward.

• Small batches are normal work for us. This project went from enquiry to a fully quoted, documented IP55 axial fan without friction of any kind. Precision matters as much as volume, and low quantity does not disqualify a customer.
• A performance upgrade at a lower price. This IP55 axial fan delivers 4017 m3/h with Class F insulation and full sealing, yet the price point sits materially below equivalent European-branded fans.
• A traceable process. The job moved through enquiry, technical review and filed drawings, always in order. For a buyer, that visible chain is what makes an odd part safe to buy.
• Papers, not just parts. The customer also got an approved part number, a full datasheet and P-Q curves. That is what a repair team needs three years later, when the next fan dies.

Browse our axial fan range, or the refrigeration and condenser fan series for cold room duty. Protection ratings are defined in IEC 60529.

Questions about this replacement

Will it run in freezing temperatures?

Yes. This IP55 axial fan is specified from -30C to +60C, which covers commercial cold storage and freezer rooms. Furthermore, the sealing, Class F insulation and maintenance-free ball bearings were all chosen so it starts reliably and runs continuously on S1 duty in cold, damp air.

What is the difference between the S and B models?

The suffix gives the airflow direction. An S model pulls air through the impeller towards the motor. A B model, used here, pushes air away from the motor. Blade geometry and motor mounting differ between the two, so choosing the wrong one costs you a large part of the airflow.

Is this a direct replacement for a WEIGUANG YWF4E-400B?

It replaces it and improves on it. The LWAA4E400B-5MEB-02-00 matches the 230V/60Hz electricals and the 400mm form factor. At 260W input it delivers 4017 m3/h, above the original 250W unit, in the same physical footprint.

Why does IP55 matter more than IP44 in a cold room?

Defrost cycles are the reason. Warm, wet air condenses on cold surfaces and runs into any opening, so the seal is tested far harder than in a dry plant room. An IP55 axial fan adds proper dust protection and resists water jets rather than mere splashes. That is what a defrost cycle actually produces.