ACMELEC HVAC Controls

Product category

FCU Thermostats for 2-Pipe & 4-Pipe Fan Coil Units

Wall-mounted fan coil unit controllers for three-speed or 0-10V fans, valve control and optional WiFi. Compare the primary AE-5503K and AE-5509K models for hotels, offices and apartments.

Request FCU Model Selection All Products
AE-5509K color display FCU thermostat angled product view AE-5503K white LCD FCU thermostat front view AE-5503K FCU thermostat installed in a room setting

Choose an FCU thermostat by pipe system, valve wiring, fan output and communication requirement—not by panel appearance alone.

FCU controller selection checklist

Before requesting a sample or quotation, confirm whether the project uses a 2-pipe or 4-pipe fan coil unit, two-wire or three-wire valves, three-speed relay or 0-10V fan control, and the available power supply. Smart projects should also specify WiFi, Modbus or BMS requirements.

OEM and project options

  • Brand logo and packaging customization
  • WiFi, Zigbee, Modbus, RF433 or 0-10V configurations where applicable
  • Project matching for hotels, apartments, offices and HVAC distributors

Primary FCU controllers

Compare AE-5503K and AE-5509K

Both main models support common fan coil project routes; select the panel and function configuration after confirming the HVAC wiring.

Application guide

What an FCU thermostat controls

  • Room temperature and heating/cooling demand
  • High, medium and low fan-speed relays, or selected 0-10V fan configurations
  • Two-wire or three-wire valve actuators according to the selected wiring version
  • Separate heating and cooling valve outputs for applicable 4-pipe systems
  • Optional WiFi app control or project communication functions

Information needed for quotation

  • 2-pipe or 4-pipe fan coil system
  • Valve actuator type and operating voltage
  • Three-speed or 0-10V fan input
  • Thermostat power supply
  • WiFi, Modbus or BMS requirement
  • Project quantity, logo and target market
Send FCU Requirements

FCU controller FAQ

Fan coil thermostat questions

How do I choose an FCU thermostat?

Confirm 2-pipe or 4-pipe, valve type, three-speed or 0-10V fan control, supply voltage and smart communication requirements.

What is the difference between a 2-pipe and 4-pipe controller?

A 2-pipe FCU uses one water circuit for seasonal heating or cooling. A 4-pipe FCU uses separate heating and cooling circuits and normally needs separate valve outputs.

Can the thermostat control an FCU valve actuator?

Yes, the correct controller version can operate common two-wire or three-wire FCU valve actuators. Confirm the actuator voltage and wiring before ordering.

Is 0-10V fan control available?

Selected AE-5503K and AE-5509K configurations support a 0-10V fan signal. Confirm the fan input and required valve outputs.

Full product range

Other FCU thermostat panel options

Use these additional panel styles after the pipe system, valve outputs and fan-control method are confirmed.

Before quotation

FCU selection information

  • 2-pipe or 4-pipe system
  • Valve type, voltage and actuator logic
  • 3-speed fan or EC fan with 0–10V control
  • Power supply, Modbus, WiFi, Zigbee, key-card or window contact

Choose by internal configuration

Products with the same front-panel design can use different fan, valve and signal configurations. Send the wiring requirement before ordering.

View samples, MOQ and OEM/ODM policy