Sourcing liquid level controllers from China

Duty on automatic liquid level controllers

Heading 9032 covers automatic regulating or controlling instruments and apparatus. For liquid-level applications, distinguish a complete controller that operates a pump or valve from a sensor that only reports a level. The table includes hydraulic or pneumatic instruments, digital valve controllers, other automatic controllers and parts; these are alternative classifications, not interchangeable codes.

Read from the UK Trade Tariff on 18 October 2026, hydraulic or pneumatic instruments carried 0% duty from China; other automatic controllers and parts carried 2%. Digital valve controllers carried 2%, with a 0.00 % autonomous suspension subject to its product scope and footnote excluding mixtures, preparations or products made up of different components containing these products. No anti-dumping or countervailing measures were recorded for these lines.

The tariff attaches fluorinated greenhouse gas import control to these lines and supplementary-unit import control to the digital valve-controller line. Confirm the applicable requirements with your customs broker using the actual product specification. Do not assume a suspension covers every liquid-level controller. Confirm the commodity code, and consult the wider thermostats and controllers guide.

Specify the liquid, sensing method and switching

State whether the controller fills or empties a tank, the liquid involved, its conductivity, temperature and tendency to foam or leave deposits. Specify probe, float or external sensor compatibility, wetted materials, cable length, mounting and cleaning access. Agree the operating level, switching differential and alarm behaviour against the actual tank arrangement.

Specify supply voltage, relay load, pump starting behaviour and whether the output drives a contactor rather than the pump directly. Agree what happens after loss of power, a disconnected probe or a stuck float. For mains-powered models, confirm with the relevant product-safety authority whether the electrical safety regulations apply and what UKCA or CE evidence is needed. The importer must ensure that covered equipment has easily understandable English instructions; arrange testing and certification around the finished model.

Worked duty example

Illustrative example, not a quote: Illustrative batch of 50 automatic liquid level controllers under 9032 89 00 90, invoiced at £3,000 free on board, with £1,000 of freight and insurance to the UK. The customs value is £4,000. Duty at 2% is £80. Import VAT at 20% is charged on the customs value plus duty, £4,080, so it is £816. Import taxes total £896; a VAT-registered importer can usually reclaim the VAT, so the lasting cost is the £80 of duty. The import duty and VAT guide explains each step.

Inspection checklist

Level response: test filling and emptying with the intended liquid, recording switching points, differential and alarm response against the agreed specification.

Fault behaviour: disconnect the sensor, simulate a stuck float and restore power; check the pump and valve outputs follow the approved fault sequence.

Electrical build: compare relay ratings, terminal markings, supply labels and wiring diagrams with the approved sample and test documentation; check loose terminals and damaged cable seals.

Arrival condition: inspect probes, floats, mounting threads, seals and enclosure damage, then repeat a functional test. Use the agreed inspection checklist to record findings.

What goes wrong

Conductive probes can respond poorly to a different liquid from the factory's test liquid. Deposits can bridge probes, floats can catch on tank walls, and foam or turbulence can produce unstable switching. A controller demonstrated in clean water may therefore behave differently in the buyer's tank.

Relay contacts can chatter when the switching differential is unsuitable, and a relay selected for a resistive load may struggle with pump starting current. Incorrect filling or emptying logic can reverse the intended action. Approve samples in the intended installation and agree fault behaviour before production.

Cambridge China Bridge sources these products for UK businesses, checking the factory and the documents before shipment. See factory verification. For components and parts, see sourcing for manufacturers.