Sourcing feedwater heaters from China

Duty on steam-heated feedwater heaters

Read from the UK Trade Tariff on 1 October 2026, heading 8404 covers boiler auxiliary plant, steam or other vapour power-unit condensers, and parts. This guide concerns steam-heated boiler feedwater heaters supplied as boiler auxiliary plant. The table groups heater configurations and dedicated parts under shared tariff codes.

The supplied tariff record shows 0% duty for goods from China across the heading, with no anti-dumping or countervailing duty, suspension or attached import control recorded. Complete boiler auxiliary plant uses 8404 10 00 00; qualifying parts use 8404 90 00 00.

Confirm the commodity code against the heater's function, drawings and supplied condition. General-purpose heat exchangers require a separate classification check. See the wider boiler auxiliary plant guide for the rest of the heading.

Specify steam duty and condensate drainage

State whether steam mixes directly with the feedwater or heats it through a tube wall. For a closed heater, specify feedwater flow, inlet and outlet temperatures, available steam conditions, allowable pressure drop, and design pressure and temperature for each side. Agree tube and shell materials, corrosion allowance, connection drawings and space for tube-bundle withdrawal.

Define condensate outlet conditions, drainage arrangements, venting, supports and the boundary between the heater and site pipework. Establish the applicable pressure-equipment classification and conformity route from the actual design before ordering. Agree the required declaration, marking and pressure-test records with the supplier.

Before qualifying pressure equipment is used, a written scheme of examination must be in place and an examination undertaken. Include this in the site's commissioning arrangements.

Worked duty example

Illustrative example, not a quote: Two horizontal steam-heated boiler feedwater heaters, illustrative order under 8404 10 00 00, invoiced at £64,000 free on board, with £5,000 of freight and insurance to the UK. The customs value is £69,000. Duty at 0% is £0. Import VAT at 20% is charged on the customs value plus duty, £69,000, so it is £13,800. With no duty, the only import tax is the VAT, which a VAT-registered importer can usually reclaim. The import duty and VAT guide explains each step.

Inspection checklist

Materials and joints: match tube, tubesheet and shell certificates to traceable markings; check weld maps, joint details and agreed non-destructive examination records.

Pressure integrity: witness the agreed pressure tests and check for external leakage and leakage between the steam and water sides. Match test records to the heater identification.

Connections and drainage: measure nozzle positions and flange details against the approved drawing; check condensate and vent connections, supports and maintenance access.

Arrival and documents: check for transport damage, displaced supports and uncapped connections. Match the nameplate, drawings and applicable conformity documents to the delivered heater. See quality inspection.

What goes wrong

A heater can miss its outlet-temperature target when the supplier designs for steam conditions that the site cannot provide. Poor condensate drainage can flood the heating surface and contribute to water hammer. Compare the proposed thermal calculation with actual site conditions and agree how performance will be checked.

Tube-joint leakage can mix the steam and feedwater circuits. Incorrect nozzle positions or inadequate withdrawal space can prevent installation or maintenance. Agree the joint inspection plan and dimensional drawing before manufacture, and resolve material or pressure-document discrepancies before shipment.

Cambridge China Bridge sources these products for UK businesses, checking the factory and the documents before shipment. See factory verification. For machinery and equipment, see machinery imports.