The short answer for an OEM buyer or project manager placing an air cooled chiller OEM order: if you only have one hour with the chiller factory, lock these three numbers — the 6-step lead time from approved drawing to factory shipment, the 4 capacity tiers from 3 HP to 200 HP, and the 18-month warranty from shipment (or 12 months from commissioning, whichever comes first) — and confirm that the factory holds CE, ISO 9001:2015, and selected UL listings with the certification pack visible on the website. Everything else on this page is the engineering rationale behind those numbers, the 4 capacity tiers we run on the Ningbo production line, and the 6-step workflow I share with every new OEM buyer in the first RFQ call.

Why Does a 6-Step Workflow Decide Whether an Air Cooled Chiller OEM Order Lands on Time?

Most late chiller OEM orders are not caused by production capacity shortages; they are caused by buyers skipping the first 3 steps and expecting the factory to fill the gap. The 6-step workflow below is the same one we run on the Ningbo production line for every air cooled chiller OEM program, and it is the only workflow that compresses the 4–12 week calendar without creating a quality dispute. I have personally walked three OEM buyers through this workflow in 2025 and the result was always the same: written RFQ at step 1, signed drawing at step 2, signed sample at step 3, and the bulk production never slipped past the agreed shipment date.

There is a second reason a 6-step workflow matters that has nothing to do with the calendar. An air cooled chiller is a high-voltage, high-refrigerant piece of equipment, and the engineering drawing is the only document that captures the buyer’s specific voltage, refrigerant, and connection-layout requirements in writing. A buyer who skips the drawing approval and asks the factory to “just ship what you have” is the buyer who ends up with a 460V/60Hz unit on a 380V/50Hz facility. The drawing is the contract; the sample is the verification; the bulk production is the delivery.

At NINGBO ROBOT we have run the same 6-step workflow for over a decade because it is the only way to align our Ningbo production line with the global OEM programs on the air cooled chiller family. The 4 capacity tiers below are the same set I share with our OEM partners in the first RFQ call.

What this article covers and what it does not

This article covers the 4 capacity tiers, the 6-step workflow, the pre-production sample gate, the pre-shipment inspection cadence, the 3-day on-site installation supervision, the certification framework, and the standard warranty. It does not cover HVAC system design, on-site plumbing, or the cost of the chiller — those belong in a separate engineering document. If you are an OEM buyer or project manager placing your first air cooled chiller OEM order, read this end to end and send the questions to the NINGBO ROBOT sales team in writing.

What Are the 4 Capacity Tiers on the Air Cooled Chiller OEM Line?

The capacity ladder below is the 4-tier view I run on the Ningbo production line for air cooled chiller OEM programs, anchored to a 3 HP entry tier and a 200 HP large-volume tier. The ladder assumes a standard refrigerant (R-410A or R-134a) and a standard voltage (3-phase 380V/50Hz or 3-phase 460V/60Hz). Custom refrigerant and custom voltage add 2–3 weeks to the lead time.

Hard numbers to remember: Tier 2 is the most common OEM program. Tier 3 is the threshold for a screw-compressor reference. Tier 4 is the entry point for a custom-tooled reference with a water-cooled option. Buyers who try to negotiate a custom-tooled reference at Tier 1 volume absorb the engineering amortisation themselves; this is a written clause in our standard OEM contract.

How Do the 6 Steps Work in Practice?

The 6 steps are sequential, not parallel, and the buyer who tries to compress them is the buyer who ends up with a partial shipment. The 6 steps below are the same sequence I share with our OEM partners in the onboarding document.

Step 1: Send the RFQ (cooling capacity, voltage, refrigerant)

The first step is a written RFQ with the cooling capacity in HP or kW, the supply voltage, the supply frequency, and the refrigerant preference. We confirm a stock or custom reference within 2 working days. The RFQ is the document that locks the engineering scope; everything downstream is built on it. Buyers who skip the written RFQ and call our sales line first are the buyers who pay for re-engineering on the drawing approval step. I have personally seen this pattern three times in 2024 and the rework cost ranged from 5 to 10 working days. I share the rework-cost data with every new OEM buyer in the first RFQ call, because the buyer who understands the rework cost is the buyer who does not skip step 1.

Step 2: Approve the engineering drawing and the layout

We send a dimensioned drawing and a connection-layout drawing within 3 working days of the RFQ. The drawings specify the unit dimensions, the refrigerant connection positions, the electrical connection positions, and the drain and vent positions. The buyer approves the engineering drawing in writing before we start production. The drawing approval is a hard gate; we do not start step 3 without it.

Step 3: Approve the pre-production sample

We build a pre-production sample within 4 weeks of the drawing approval. The buyer visits our factory to inspect the sample for cooling performance (capacity test), electrical safety (insulation resistance, ground continuity), and noise level (dB(A) at 1 m). The sample is the reference for the entire bulk run; we do not start step 4 without the written sample approval.

Step 4: Confirm the production slot and the PO

The buyer confirms the production slot and issues the PO. We book the slot in the 6-step lead-time plan and start material procurement within 5 working days of the PO. The material PO covers copper tubing, compressors, condenser coils, electrical panels, and refrigerant. The material cost exposure is highest in the first 5 days; buyers who delay the PO past 7 days from sample approval absorb the price exposure. I sign off on every material PO within 24 hours of receipt to keep the cost exposure window narrow.

Step 5: Run the pre-shipment inspection

We pull a pre-shipment sample on every lot. We run the cooling-capacity test (per AHRI Standard 550/590), the electrical-safety test (per IEC 60335-2-40), and the noise-level test (dB(A) at 1 m per ISO 3744). We share the test report with the buyer before the unit is sealed for shipment.

Step 6: Ship from Ningbo per the agreed incoterm

We ship FOB Ningbo, CIF, or DDP per the agreed incoterm. Sea freight is 22–30 days to a US West Coast port and 30–38 days to a US East Coast port. Air freight is 5–7 days. The 3-day on-site installation-supervision service is available on orders shipped outside China, and the service is documented in the OEM contract before the first shipment.

How Does the Heating & Cooling Series Fit the OEM Program?

The air cooled chiller is one reference inside the larger heating and cooling OEM series, and the series has its own capacity ladder and its own certification framework. Below is how the air cooled chiller fits the family.

Air cooled chiller (this article)

The reference covered in this article. Standard refrigerant: R-410A or R-134a. Standard voltage: 3-phase 380V/50Hz or 3-phase 460V/60Hz. Standard capacity: 3–200 HP. Lead time: 4–12 weeks.

Water-cooled screw type chiller

The high-capacity sibling at water-cooled screw type chiller. Standard refrigerant: R-134a. Standard voltage: 3-phase 380V/50Hz or 3-phase 460V/60Hz. Standard capacity: 60–500 HP. Lead time: 10–14 weeks. The screw-compressor option is for facilities that need continuous-duty cooling with a tighter temperature tolerance than the scroll compressor.

Mold temperature controller

The plastic-injection-molding sibling. Standard capacity: 6–36 kW. Lead time: 2–3 weeks. The mold temperature controller is the fastest-moving reference in the family and the most common OEM program for small-batch injection molders.

How Does the Certification Framework Work?

The certification framework is the second parameter that decides whether an air cooled chiller OEM order survives the customs and the on-site commissioning. NINGBO ROBOT’s standard compliance framework is as follows.

• CE marking on the air cooled chiller family for the European market.
• ISO 9001:2015 quality management across the production line.
• UL listing on selected references for the North American market.
• RoHS and REACH documentation on the electrical panel and the refrigerant circuit, on request.

The full certification pack is on the factory page. The pack is updated annually and we share the latest version on the first RFQ. For North American projects that require UL-listed references, we recommend the buyer request the UL file number on the engineering-drawing approval step, because the UL file number is the only document the AHJ (Authority Having Jurisdiction) accepts on the installation permit.

How Does the 3-Day On-Site Installation Supervision Work?

The 3-day on-site installation supervision is the operational lever that decides whether the chiller starts running on day 1 without a dispute. The service is available on orders shipped outside China, and the scope is fixed.

Day 1: Installation and connection

The NINGBO ROBOT engineer arrives on day 1 to supervise the uncrating, the positioning, the refrigerant connection, the electrical connection, and the drain and vent connection. The engineer walks the buyer’s installation team through the same checklist that the factory team uses on the line in Ningbo.

Day 2: Commissioning and operator training

The engineer runs the commissioning test on day 2: power-on, refrigerant charging (if not pre-charged), control-panel setup, and the first-load test. The operator-training session is a 3-hour walk-through of the control panel, the alarm log, the maintenance schedule, and the spare-parts list.

Day 3: Final inspection and report

The engineer runs the final-inspection test on day 3: cooling-capacity verification, electrical-safety verification, and the noise-level verification. The engineer signs the post-installation inspection report and the report is the document the buyer files with the AHJ or the local utility for the installation permit.

A short note from Mr. Chen on the 6-step workflow: I designed this workflow in 2018 and I have personally reviewed every RFQ that has come through the air cooled chiller OEM line since then. I have walked seven new OEM buyers through the workflow in 2024–2025 and the conversion rate from RFQ to signed annual contract is significantly higher when the 6 steps are followed in writing on day 1. I share the same workflow with the NINGBO ROBOT sales team in our internal training, and I am personally available for the first RFQ call with every new OEM buyer. I run every certification pack and I review the pre-shipment test report on a quarterly cadence; the 18-month warranty and the 4–12-week lead time are the two numbers I keep pinned on my desk.

Frequently Asked Questions