Sourcing hydronic unit heaters from China

UK duty on hydronic unit heaters

Heading 7322 includes iron or steel air heaters incorporating a motor-driven fan, where the heat is not generated electrically. A hydronic unit heater transfers heat from circulating hot water through a coil while its fan moves air. The relevant supplied line is 7322 90 00 90; the table shows variants sharing that code.

Read from the UK Trade Tariff on 30 September 2026, the supplied line carries 2% duty for goods from China. No anti-dumping or countervailing duty, suspension, steel measure or import control is listed in the supplied facts. This tariff snapshot does not establish product safety compliance.

Give your broker the casing material, heating method, fan details and whether the shipment contains complete units or parts, then confirm the commodity code. For the wider heating family, see gas-fired warm-air unit heaters. For direct-fired diesel models, see sourcing direct-fired diesel heaters.

Specify output at your water temperatures

Ask for heat output at your intended water supply and return temperatures, entering-air temperature, water flow and fan setting. Specify water-side pressure drop, maximum operating pressure, coil material, connection threads and connection position. A headline output without its operating conditions cannot support a like-for-like comparison.

Agree airflow, air throw, noise test conditions, motor supply, speed control and thermostat interface. Specify mounting orientation, bracket drawings, unit weight and access for coil cleaning. Request a sample run with the proposed controls.

Before placing products on the market, importers must be able to demonstrate compliance with relevant regulations and safety requirements. Ask a testing and certification adviser to establish the applicable requirements for the complete heater, including its fan assembly and pressurised coil.

Worked duty example

Illustrative example, not a quote: Illustrative order of 50 wall-mounted hydronic unit heaters under 7322 90 00 90, invoiced at £32,000 free on board, with £4,000 of freight and insurance to the UK. The customs value is £36,000. Duty at 2% is £720. Import VAT at 20% is charged on the customs value plus duty, £36,720, so it is £7,344. Import taxes total £8,064; a VAT-registered importer can usually reclaim the VAT, so the lasting cost is the £720 of duty. The import duty and VAT guide explains each step.

Inspection checklist

Coil: witness the agreed leak test, inspect joints and confirm the coil matches the approved drawing; check for crushed fins and damaged connection stubs.

Fan and controls: run each sampled unit through its agreed settings; check rotation, vibration, rubbing, thermostat response and the wiring against the approved diagram.

Mounting: measure bracket holes and connection positions; check fixings, louvre movement and access for maintenance against the installation drawing.

Arrival: inspect casing corners, coil protection and cartons before handling; record damage and compare model identification with the order and test records. Use a product-specific inspection brief.

What goes wrong

Output disappoints when a supplier quotes hotter water or a faster fan setting than the installed system uses. Excessive coil pressure drop can also reduce water flow. Agree the operating conditions and obtain supporting performance data before accepting the model.

Coil joints can leak, fans can rub after transport and brackets can leave inadequate cleaning access. Check the approved sample in its intended orientation, protect the coil and connections in packing, and retain matching drawings and production test records.

Cambridge China Bridge sources these products for UK businesses, checking the factory and the documents before shipment. See factory verification. For repeat volumes, see container programmes.