Sourcing HVAC components from China is not the gamble it was fifteen years ago. The hard part now is not finding a factory. It is working out which of the forty suppliers replying to your enquiry actually manufactures anything, which holds the approvals your market demands, and which will still be answering emails in year three of the contract.
We sit on the other side of that conversation every week. Buyers arrive with a specification and a deadline, and the questions they ask tell us immediately how much sourcing experience is behind them. The experienced ones ask about tooling ownership and golden samples in the first email. The inexperienced ones ask for the lowest price and a free sample, and they are usually the ones who end up with a container of parts that fail inspection in Rotterdam.
This guide is the checklist we wish every buyer worked through. It covers how to tell a manufacturer from a trading company, which certifications genuinely apply to HVAC valves and controls, how MOQ is actually calculated, and what to lock down in writing before money moves.
Factory or Trading Company, and Why It Changes Everything
Start here, because every other decision depends on the answer.
A trading company is not fraudulent. Some are excellent, and they earn their margin by consolidating a mixed order across several factories so you deal with one invoice instead of six. If you need manifolds, pipe, thermostats and pumps in one shipment and you are buying small volumes, a good trading company saves you real work.
What you lose is control. You cannot walk the production line. You cannot sit with the engineer who will actually change the tool. When a dimension comes back wrong, your correction passes through an intermediary who has no technical stake in getting it right. And on a component with an engineering change midway through a programme, that gap costs weeks.
What the Business Licence Tells You
Ask for the business licence, the 营业执照. Every legally operating Chinese company has one, and it is not a confidential document. Then read the scope of business field.
A manufacturer’s scope includes production terms. A trading company’s scope lists wholesale, retail, or import and export, with no production language at all. That single field settles the question faster than any amount of email.
Cross-check three more things:
- Registered capital. Not decisive, but a manufacturer running injection moulding and CNC lines does not operate on a token registration.
- The company name on the bank account. It must match the business licence exactly, character for character. Payment to a personal account, or to a Hong Kong entity with a different name, is the single most common pattern in sourcing fraud.
- Who issues the certificate of origin. A real factory issues a CO or Form E in its own name. A trading company cannot.
The Engineering Question Test
This one is free and it works.
Send a question that only production can answer. Ask what glass fibre content the actuator housing uses and why. Ask what the flow meter calibration tolerance is across its range. Ask whether the brass is CW617N or CW602N and what the dezincification behaviour means for your water chemistry.
A manufacturer answers in a day, often in the same reply, sometimes with a correction to your assumption. A trading company goes quiet for three days and comes back with a paraphrase. You will know.
For reference, our own thermal actuators use PA6 with 30 percent glass fibre for dimensional stability under repeated thermal cycling, and we will tell you that before you ask, because a buyer who understands the material is a buyer who specifies correctly.
What China Actually Competes On Now
It is worth correcting an assumption that still shows up in sourcing conversations, because acting on it leads to bad supplier choices.
China is no longer the low wage option. Manufacturing wages along the coastal belt, which is where the HVAC component industry sits, are now substantially higher than Vietnam, Indonesia, India or Bangladesh. If labour cost were the only variable, none of this industry would still be here.
What China competes on is density. Within a two hour drive of our facility in Jiaxing there are brass forgers, plating lines, injection moulders, wax element producers, PCB assemblers, packaging printers, and three container ports. A tooling change that takes six weeks elsewhere takes ten days here because the mould shop is forty minutes away and its owner answers his phone on a Sunday.
That is the actual advantage, and it matters to you directly. It means shorter development cycles, faster response to an engineering change, and a lower risk of a single component holding up an entire assembly.
Regional Specialisation Is Real
Geography narrows your search considerably.
- Zhejiang and Jiangsu. Valves, fittings, manifolds, pumps, underfloor heating components. Yuhuan and Yongkang in particular for brass valve bodies.
- Guangdong. Consumer electronics, air conditioning, appliances, anything with significant PCB content.
- Shandong and Anhui. Heavier equipment, some heat pump assembly.
A supplier offering you brass manifolds from Guangdong and air purifiers from Zhejiang is almost certainly not making either. Specialisation is geographic, and a quote that ignores the map is a quote from a middleman.
Certifications That Matter, and One That Is Widely Misunderstood
Buyers routinely ask for “CE certificate and ISO” and stop there. That request is incomplete in a way that matters legally.
CE Marking Is a Declaration, Not a Certificate
For most HVAC components there is no such thing as a CE certificate issued by an authority. CE marking is a manufacturer’s self declaration that the product conforms to the applicable EU directives.
What you must obtain is the Declaration of Conformity, signed by the manufacturer, naming the specific directives and the harmonised standards used. Behind it should sit the test reports that support each claim. A one page document from a Chinese test house headed “CE Certificate” is not a Declaration of Conformity, and if your market authority audits you, it will not protect you.
Which directives apply depends on the component:
- Low Voltage Directive 2014/35/EU for mains powered devices such as actuators, thermostats and wiring centres.
- EMC Directive 2014/30/EU for anything with electronics.
- RoHS 2011/65/EU restricting ten substances, including four phthalates added in the 2015 amendment.
- Pressure Equipment Directive 2014/68/EU for pressure bearing parts above the threshold. Note that many small components fall under Article 4.3, meaning they are built to sound engineering practice and must not carry a CE mark for PED. A supplier who CE marks a small pressure fitting under PED has misunderstood the regulation.
- REACH, where you need an SVHC declaration against the current candidate list, refreshed as the list updates.
ISO 9001 is worth having but understand what it certifies. It attests to a quality management system, not to product quality. A factory can hold ISO 9001 and ship you defective parts, entirely consistently, if its documented process permits it.
Water Contact Approvals Are Market Specific
This catches people out on manifolds, mixing valves and anything touching potable water. There is no single global approval.
- UK: WRAS approval, or a recognised regulation 4 equivalent.
- Germany: DVGW, with KTW-BWGL assessment for the materials.
- France: ACS.
- North America: NSF/ANSI 61 for health effects, plus NSF/ANSI 372 for the lead free requirement.
Ask which approvals the factory actually holds, for which specific part numbers, and check the expiry. An approval that covers one valve body does not automatically cover the next size up, and buyers discover this at customs rather than at quotation.
For underfloor heating specifically, pipe should carry oxygen barrier certification to DIN 4726, and the system design should reference EN 1264.
Refrigerant Rules If You Are Buying Heat Pumps
For any equipment containing refrigerant, the EU F-Gas Regulation governs what you can place on the market and when. R32 carries a GWP of 675 against R410A at 2088, which is why almost all new residential capacity has moved to R32. Verify the refrigerant charge, the GWP, and the Ecodesign and ERP documentation for the specific model, not for the range. Our heat pump documentation is issued per model for exactly this reason.
Understanding MOQ Instead of Arguing With It
Minimum order quantity is usually treated as a negotiating position. Most of the time it is arithmetic.
MOQ on an injection moulded part is driven by resin batch size and colour changeover. Purging a machine from black to white consumes material and machine hours that have to be recovered somewhere. MOQ on a brass component is driven by billet batch and the plating line’s minimum load. Neither number is arbitrary, and a supplier who drops MOQ by 80 percent without explanation is either quoting from stock, subcontracting, or planning to substitute material.
The productive question is not “can you lower the MOQ”. It is “what drives the MOQ”. Then you have levers:
- Accept the factory’s standard colour and standard packaging.
- Combine several SKUs into one production run so the setup cost spreads.
- Place a blanket order at volume price with staged releases across the year.
- Take the first order at the factory’s standard specification and introduce your customisation at the second, once volume justifies the tooling.
That last one saves more money than any price negotiation, and almost nobody proposes it.
The Sample Sequence That Prevents Disputes
Samples run in three stages, and skipping a stage is where disputes come from.
Stage one, the off-the-shelf sample. The factory’s existing product, unmodified. You are assessing baseline build quality, material, and finish. Pay for it. A supplier handing out free samples without discussion is usually a trading company buying goodwill with someone else’s product.
Stage two, the modified sample. Your changes applied. Expect to pay tooling or setup, and expect two iterations. Document every dimension you care about with a tolerance, because “same as the drawing” is not a specification either side can hold the other to.
Stage three, the pre-production or golden sample. Made on the production tool, on the production line, with production material. Both parties sign it, both parties keep one, and that physical object becomes the reference for every subsequent inspection. If a shipment is disputed later, the golden sample is what the argument is measured against.
Do not let a supplier talk you out of stage three on the grounds that stage two was fine. A hand-finished stage two sample and a tool-made stage three part can differ meaningfully, and the difference is exactly what you need to see before committing to a container.
Tooling, Designs and Brand Protection
Three things to settle in writing before the first payment.
Who owns the mould. If you paid for tooling, the contract should say you own it, state the amortisation, and give you the right to have it transferred. Without that clause you have funded a tool that stays on the supplier’s floor, and your leverage in every future price negotiation is gone. Get the tool number and photographs of the tool with its identification plate.
Register your trademark in China. China operates first to file. Your registration at home gives you nothing here. If someone else registers your mark, they can legally block your goods from leaving Chinese customs, and buying it back is expensive. Registration is cheap by comparison and can be filed directly or via Madrid Protocol designation.
Use an NNN agreement, not an NDA. A Western style NDA is close to ornamental in a Chinese dispute. What works is a non-disclosure, non-use, non-circumvention agreement drafted under Chinese law, written in Chinese, with a named Chinese court as the jurisdiction and a stated contractual penalty. The penalty clause matters because it lets a Chinese court act without you first proving quantified damages.
If the housing design is distinctive, a Chinese design patent is inexpensive and issues quickly. It is worth doing before the tool is cut, not after a copy appears.
Inspection Before the Container Leaves
Inspecting on arrival is inspecting too late. Once the goods are in your warehouse, your only remedy is a commercial argument with a supplier who has already been paid.
Three inspection points, and you do not need all three on every order:
- Pre-production inspection. Verifies incoming material against specification. Worth it on a first order or after a material change.
- During production inspection, or DUPRO. Carried out at roughly 20 to 30 percent completion, while there is still time to correct a systematic fault. This is the highest value inspection and the one most often skipped.
- Pre-shipment inspection. Sampled against ISO 2859-1 with an agreed AQL. For HVAC components, 2.5 for major defects and 4.0 for minor is a common and reasonable level. Agree the AQL in the contract, not at the inspection.
Add container loading supervision on high value or fragile shipments. It costs very little and it catches the mistakes that happen in the last hour, when the loading crew is working from a packing list they did not write.
Incoterms, Payment and the Lead Time Nobody Plans For
Quote comparisons fall apart when the Incoterm differs, so fix it early. Under Incoterms 2020, FOB is the usual default from China and it is a sensible one: the supplier handles Chinese export clearance and delivery to the vessel, you control the freight. Avoid EXW unless you have a forwarder who genuinely handles Chinese export documentation, because otherwise you have taken on a customs process you cannot execute. CIF or DAP shift more to the supplier, at the cost of your freight visibility.
Payment terms that are normal and defensible: 30 percent deposit with the order, 70 percent against a copy of the bill of lading. Letter of credit at sight for larger programmes. Telegraphic transfer to the company account whose name matches the business licence. Never to a personal account, never to a differently named entity, and never a full advance payment on a first order.
Then build the calendar honestly:
- Production after golden sample approval: typically 25 to 45 days for HVAC components.
- Sea freight to Northern Europe: roughly 30 to 40 days port to port. US West Coast: 18 to 30.
- Chinese New Year. Production stops for two to four weeks, with a slowdown before and a staffing ramp after. Orders that must land in Q1 need to be placed in November, not January. This single factor causes more missed deadlines than every quality issue combined.
- National Day in early October is a shorter second shutdown.
A Practical Qualification Checklist
Condensed, in the order we would work through it:
- Business licence obtained, scope of business confirms production.
- Bank account name matches the business licence exactly.
- Engineering question answered directly and correctly.
- Declaration of Conformity received, naming directives and standards, with supporting test reports.
- Market specific water or refrigerant approvals confirmed against your actual part numbers.
- MOQ explained in terms of material batch or setup, not asserted.
- Golden sample made, signed and retained by both parties.
- Tooling ownership and amortisation stated in the contract.
- Trademark filed in China. NNN agreement in Chinese, Chinese jurisdiction.
- AQL and inspection points agreed in writing before production starts.
- Incoterm fixed, payment terms staged, no advance in full.
- Chinese New Year built into the delivery schedule.
Work through that list and most sourcing failures never happen. Skip it and you will meet them in order.
Working With Legom
Jiaxing Legom Technology Co., Ltd. manufactures HVAC and water control components from Jiaxing, Zhejiang, and supplies to more than 90 countries.
Our range covers thermal actuators and the wax thermostatic elements inside them, underfloor heating manifolds in stainless steel and brass, HVAC and safety valves, room thermostats and wiring centres, air to water heat pumps, and air purifiers.
We work on both OEM and ODM terms. Our OEM and ODM service covers tooling development, material specification, private label packaging and documentation packs for your market. If you are still deciding which arrangement suits your position, our explainer on what ODM means sets out the difference plainly. We are also an Alibaba verified factory, which means the licence and premises have been independently inspected rather than self declared.
Send us the specification and the market it ships to, and we will come back with the documentation position before we come back with a price.
Frequently Asked Questions
How can I tell if a Chinese supplier is a factory or a trading company?
Read the scope of business on the business licence. A manufacturer’s scope includes production; a trading company’s lists only wholesale, retail or import and export. Then ask a detailed engineering question and time the reply.
Is a CE certificate from a Chinese test lab enough?
No. For most HVAC components, CE marking is a manufacturer self declaration. You need the signed Declaration of Conformity naming the applicable directives and harmonised standards, plus the test reports behind it. A standalone “CE certificate” is not that document.
Can I get a Chinese factory to lower its MOQ?
Sometimes, but the better approach is to ask what drives it. Accepting standard colour and packaging, combining SKUs into one run, or placing a blanket order with staged releases usually moves the number further than price pressure does.
Who owns the mould if I pay for tooling in China?
Only whoever the contract says. Ownership does not transfer automatically because you paid. Get a written clause stating ownership, the amortisation, your right to transfer the tool, and the tool identification number.
Is an NDA enforceable against a Chinese supplier?
A Western style NDA is weak in practice. An NNN agreement covering non-disclosure, non-use and non-circumvention, drafted under Chinese law in Chinese with a Chinese court named and a contractual penalty stated, is the version a Chinese court can act on.
How far ahead should I order around Chinese New Year?
Production halts for two to four weeks with a slowdown either side. For goods that must arrive in Q1, place the order in November and confirm the golden sample before December.
What AQL should I specify for HVAC components?
Sampling to ISO 2859-1 at AQL 2.5 for major defects and 4.0 for minor is a common and defensible level. Agree it in the contract before production begins, not on the day of inspection.
“The buyers who never have problems are the ones who ask about documentation before they ask about price. When someone opens with the Declaration of Conformity, the water approval for their market and who owns the tool, the whole relationship starts on the right footing, because those are the questions a real factory can answer and an intermediary cannot. We would rather lose an enquiry on price than win it and fail an inspection in the destination port.”
— Maggie Shen, Director of Legom
Reviewed by Maggie Shen, Director at Legom, on September 27, 2026. This article was reviewed for accuracy on export practice, including the business licence scope of business check, the distinction between a CE Declaration of Conformity and a test house certificate, PED Article 4.3, market specific potable water approvals, ISO 2859-1 AQL sampling levels, and Incoterms 2020 usage.