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.

Model comparison

AE-5503K vs AE-5509K: which FCU controller fits your project?

Start with the required wiring configuration, then choose the display and housing. Fan-output and WiFi options must be specified when requesting a sample; the model name alone does not identify every option.

Comparison based on the linked ACMELEC model pages and English manuals
Selection pointAE-5503KAE-5509K
Display and housingWhite LCD; tempered glass front and PC housingColor display; tempered glass front and aluminium-alloy housing
Water system2-pipe or 4-pipe, by configuration2-pipe or 4-pipe, by configuration
Fan outputThree-speed relay or selected 0–10V versionThree-speed relay or selected 0–10V version
Valve controlHeating/cooling on/off outputs according to wiring versionHeating/cooling on/off outputs according to wiring version
Supply110–230VAC, 50/60Hz110–230VAC, 50/60Hz
Temperature setting5–35°C; ±1°C control accuracy5–35°C; ±1°C control accuracy
Remote controlOptional Smart Life WiFi versionOptional Smart Life WiFi version
Product detailsAE-5503K specifications and wiringAE-5509K specifications and wiring
English manualDownload AE-5503K manual (PDF)Download AE-5509K manual (PDF)

For Modbus, Zigbee, key-card or window-contact requirements, request confirmation of the exact hardware and firmware configuration. Do not assume these options are included in the WiFi version.

System selection

Choose 2-pipe or 4-pipe control

A 2-pipe fan coil uses one water circuit for heating or cooling. Confirm the site's changeover arrangement and the valve actuator wiring. A 4-pipe system uses separate heating and cooling circuits; specify both valve outputs when selecting the controller.

Send the fan coil wiring diagram and the actuator label, including voltage and two-wire or three-wire operation. The terminal layout must match the selected controller version.

Fan selection

Choose three-speed relay or 0–10V fan output

For a three-speed fan, specify the high, medium and low speed connections. For an EC fan requiring a 0–10V input, request the corresponding signal-output version and provide the fan's input specification.

The 0–10V fan signal and valve-control outputs are separate selection points. Confirm both before approving the sample wiring.

Prepare an FCU sample request

  1. Choose AE-5503K or AE-5509K for the preferred display.
  2. Attach the fan coil wiring diagram and fan/valve labels.
  3. Specify 2-pipe or 4-pipe, supply voltage, fan output and communication requirements.
  4. Include sample quantity, estimated project quantity, destination country and any logo or packaging requirements.

FCU wiring, WiFi options and sample acceptance guide

Confirm the configuration before quotation

ACMELEC quotes according to the agreed electrical configuration, quantity and customization scope. Include your requirements in the enquiry so the proposed sample and quotation match the project.

Enquire about AE-5503KEnquire about AE-5509K

Sample and OEM/ODM procurement policy

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