Quick answer: To buy industrial dehumidifiers from a Chinese factory with confidence, fix four things in writing before you pay a deposit: the duty (room conditions and water to remove), the capacity at a stated rating condition, the certificates required in your market for that exact model, and a measurable acceptance test before shipment. Then agree the Incoterm, packing and spare parts. Most problems buyers report — units that underperform, customs holds, missing parts — trace back to one of these being left vague.
Quick answer
- Compare capacity only at the same temperature and RH (for example 30 °C/80 % RH).
- Ask for test reports and certificates that name your model, not just the company.
- Witness or video-witness a run test before the balance payment.
- Confirm dangerous-goods shipping rules early if the unit uses R290.
Step 1: Write down the duty before you ask for prices
A supplier can only quote the right machine if they know the job. Send:
| Item | Example | Why it matters |
|---|---|---|
| Space size and use | 2,000 m² warehouse, 8 m high, cardboard stock | Sets moisture sources and air distribution |
| Room temperature range | 12–28 °C across the year | Refrigerant capacity drops in cold air; may need desiccant |
| Target | Below 55 % RH | Sets how dry the air must be |
| Moisture sources | Dock doors open 6 h/day, no process water | Main load in most warehouses |
| Power supply | 380–415 V, 3-phase, 50 Hz | Wrong voltage or frequency is a costly mistake |
| Installation | Floor-standing, ducted, or ceiling | Decides the product family |
| Drainage | Floor drain nearby or pump needed | Industrial units remove hundreds of litres a day |
Mark which numbers are measured and which are estimates. If you do not know the moisture load, ask the supplier to calculate it and show the assumptions. Our guide to how much water a dehumidifier collects in a day explains the inputs.
Step 2: Compare capacity at the same rating condition
Chinese factory catalogues usually quote daily capacity at 30 °C / 80 % RH. Some brands use 27 °C / 60 % RH, and US ratings for portable units have used 65 °F (18.3 °C) since 2019, down from 80 °F (26.7 °C) (ENERGY STAR). The same machine removes far less water at the lower condition, so a "90 L/day" figure from one supplier and a "50 L/day" figure from another may describe similar units.
Ask every supplier for:
- capacity at their rating condition, and at your expected room condition;
- whether each figure was measured, calculated or interpolated;
- power input at the same conditions, and what it includes (compressor and fan; for desiccant units also the reactivation heater).
Desiccant dehumidifiers are usually rated at 20 °C / 60 % RH. Never compare a desiccant L/day figure directly with a refrigerant one.
Step 3: Specify the configuration in a schedule
Write a one-page configuration schedule and attach it to the purchase order:
- model, capacity, airflow and, for ducted units, external static pressure;
- refrigerant (R410A, R32 or R290) and its charge;
- power supply, plug or terminal type, and control voltage;
- controls: built-in humidistat, remote sensor, dry contacts, RS485/Modbus;
- coil coating, casing material and filter grade;
- drain connection size, condensate pump, and any options such as hot-gas defrost or heating.
If the supplier proposes a substitute component or model, ask for an updated schedule in writing. This is the document you will check the shipped unit against.
Step 4: Check certificates and test reports for your market
A certificate is useful only if it covers the model you are buying and the market you are selling into. Check the issuer, the model list, the standard and the date on each one.
| Market | What buyers usually ask for |
|---|---|
| European Union | CE marking with a Declaration of Conformity under the Low Voltage (2014/35/EU) and EMC (2014/30/EU) Directives, plus RoHS; safety tests to EN 60335-2-40 |
| United Kingdom | UKCA or CE marking, with equivalent declarations |
| United States and Canada | Listing to UL 474 / CSA C22.2 No. 92 from a nationally recognized testing laboratory |
| Many other markets | IEC CB test certificate and report to IEC 60335-2-40, used to obtain national approvals |
An ISO 9001 certificate shows that the company has a quality-management system; it says nothing about the safety of a particular dehumidifier. Rules change and vary by product and use, so have your importer or compliance adviser confirm the list for your project.
Step 5: Look at how the factory builds and tests
A factory visit, a third-party inspection or a live video tour is worth the time if it looks at the process, not the showroom. Ask to see:
- incoming inspection of compressors, coils and controllers;
- refrigerant leak testing and charging;
- electrical safety tests on every unit (earth continuity, insulation resistance, hi-pot);
- the performance test room, and how often production units are tested in it;
- traceability: can a serial number be traced to its components and test record?
What we show buyers at Yakeclimate: we manufacture in China, and we share the routine test records for the units on your order, and the capacity test method used for the model quoted. Ask us for them with your quotation.
Step 6: Agree a measurable acceptance test
Write the test before the units are built. A good pre-shipment test states:
- Conditions: inlet temperature and RH, and how they are held steady.
- Instruments: what measures temperature, humidity, power and water, and their calibration.
- Duration and stabilization: for example, readings after 1 hour of steady running, over at least 2 hours.
- Pass criteria: capacity and power within an agreed tolerance of the schedule.
- Function checks: humidistat, alarms, defrost, drain pump, remote control and any BMS signals.
- Records: photos, video and a signed test sheet for each serial number.
Pay the balance after the test passes. A factory test does not replace site commissioning: the room, ducts and power on site differ. Record the commissioning readings as the baseline for later service.
Step 7: Compare the full scope, not the unit price
Put quotations side by side with the same scope:
| Item | Check that it is included or priced |
|---|---|
| Units and accessories | Remote sensor, duct flanges, wheels, filters |
| Spare parts | Filters, fan, controller, drain pump, contactor |
| Documents | Manual, wiring diagram, spare-parts list, test records |
| Packing | Export wooden crate or carton; marking for upright transport |
| Incoterm | EXW, FOB, CIF or DAP (Incoterms 2020) and the named port or place |
| Lead time | Production days after deposit, and test date |
| Warranty | Period, what is covered, and how parts are sent |
| Support | Remote commissioning help, response time, language |
Under FOB, the factory delivers the goods on board at the Chinese port and you arrange the ocean freight; under CIF, the seller pays freight and minimum insurance to your port, but risk passes when the goods are loaded in China. Agree who handles customs clearance, duties and delivery to site.
Step 8: Plan shipping, especially for R290 units
- R290 (propane) units contain a flammable refrigerant. Refrigerating equipment containing a flammable gas can fall under the dangerous-goods rules for sea and air freight (UN 3358), depending on the charge. Ask your freight forwarder early, because it affects booking, labels and cost. See R290 vs R410A dehumidifiers.
- Ship upright and protect the controls; refrigerant units should stand before first start if the manual says so.
- Check on arrival: inspect crates before signing, photograph damage, and compare serial numbers with the test records.
Common mistakes to avoid
- Choosing by capacity alone without the rating condition.
- Accepting a company-level certificate for a product-level requirement.
- Ordering 60 Hz units for a 50 Hz site, or the reverse.
- Forgetting the drain route for hundreds of litres a day.
- Paying in full before any test evidence.
Send us your project
Send the space, temperature and humidity range, target, power supply and installation type. We will propose the model, show its capacity at your conditions, and list the test records and documents that come with it. Compare our industrial dehumidifiers, ceiling-mounted and ducted units and desiccant dehumidifiers.
FAQ
Frequently asked questions
Is it safe to buy industrial dehumidifiers from China?
Yes, if you buy against a written specification, check model-specific certificates, and test before shipment. These steps protect you whatever country the factory is in.
What is the minimum order quantity?
It depends on the model and options. Standard models can often be ordered in small quantities; custom voltages, coatings or branding usually need a larger order. Ask each supplier for their MOQ per configuration.
How long does production take?
Typically a few weeks for standard models, longer for custom configurations, plus ocean transit. Get the production days, test date and shipping date in the contract.
Can a Chinese factory supply my own brand (OEM)?
Many can. Agree who holds the certificates: a certificate in the factory's name may need to be extended or reissued for your brand and models.
What capacity rating should I ask for?
Ask for the capacity at the supplier's rating condition and at your own room condition, with the method used.
Sources
- International Chamber of Commerce, Incoterms® 2020.
- European Commission, Low Voltage Directive 2014/35/EU and EMC Directive 2014/30/EU.
- IEC 60335-2-40, Safety of household and similar electrical appliances: particular requirements for electrical heat pumps, air-conditioners and dehumidifiers.
- UL 474, Standard for Dehumidifiers.
- ENERGY STAR, Dehumidifier testing and capacity.
- UN Recommendations on the Transport of Dangerous Goods, entry UN 3358.
