How to fix
Confirm proper flow of hot/chilled water from the building’s central system with your building manager or maintenance team.
Fan coil systems rely on central building systems to supply hot or chilled water for your fan coil to treat the air in your suite. Typically, if your suite is not reaching the set temperature of your thermostat (either in heating or cooling mode), the issue is with your building’s central boiler or chiller.
Heat pump systems rely on a building-wide water loop, which maintains a moderate temperature with a central boiler and cooling tower. Your heat pump uses this tempered water to either absorb or reject heat, depending on whether the system is in heating or cooling mode. While the thermostat controls the fan and compressor inside the suite, the overall system performance depends on the building’s central infrastructure working correctly.
Before proceeding to the next troubleshooting steps, confirm with your building manager or maintenance team that the central water boiler/chiller/cooling tower is working correctly and that no other residents are experiencing issues
Choose your thermostat model to proceed troubleshooting:
Unilux Pro AM Thermostat
2. Ensure the temperature sensor is functioning
The thermostat may have an incorrect temperature reading, forcing the fan coil to turn off before reaching the true set temperature. You can test the accuracy of the thermostat reading by using a thermometer to measure the temperature near the thermostat.
If the temperature does match, the thermostat may be located where sunlight or drafts are impacting the temperature directly around it. If the temperature does not match the thermostat’s reading, the thermostat’s temperature sensor may be faulty, and a replacement is needed.
If further troubleshooting is required, please book a service appointment with a qualified HVAC technician to proceed.
Warning: The following troubleshooting steps should only be followed by a certified HVAC technician. If you are a resident, please contact your local HVAC repair service.
3. Ensure valve actuators are responding to system call
Use a multimeter to confirm that the thermostat is sending a voltage signal (24V AC) to the valve actuator when heating or cooling is called for.
Remove the front plate of the thermostat by gently prying it from the wall-mounted rear plate.
Place one probe on the common terminal (C)
To test call for cool: place the other probe on terminal Y
To test call for heat: place the other probe on terminal W
If a reading of ~24 VAC appears, the thermostat is sending the appropriate system call. If the actuator does not respond, a replacement is needed. If there is no voltage reading, the thermostat may not be wired correctly or may be faulty. See installation instructions for more details.
Universe Thermostat
2. Ensure the temperature sensor is functioning
The thermostat may have an incorrect temperature reading, forcing the fan coil to turn off before reaching the true set temperature. You can test the accuracy of the thermostat reading by using a thermometer to measure the temperature near the thermostat.
If the temperature does match, the thermostat may be located where sunlight or drafts are impacting the temperature directly around it. Verify by using the same thermometer to measure the temperature of another room that feels similar to the rest of the suite. If the reading is different, the thermostat will need to programmed with a temperature offset. Instructions for setting a temperature offset can be found here.
If the temperature does not match the thermostat’s reading, the thermostat’s temperature sensor may be faulty, and a replacement is needed.
If further troubleshooting is required, please book a service appointment with a qualified HVAC technician to proceed.
Warning: The following troubleshooting steps should only be followed by a certified HVAC technician. If you are a resident, please contact your local HVAC repair service.
3. Verify thermostat is set to correct system mode
Failure to connect the thermostat to the correct system mode will cause the HVAC system to not operate as expected and may lead to damage to the fan coil. You can verify and change the system mode with the following steps:
Press the gear icon on the top right of the thermostat screen.
Select “Installer Setup” from the list of options.
Enter the installer password *please contact us if you require a password
Select “System Option” from the left-hand settings menu. Select either the “Fan Coil” or “Heat Pump” radio option.
If using a fan coil, continue to the “Fan Coil” button from the left-hand settings menu. Select either “2P” for a 2-pipe system, or “4P” for a 4-pipe system.
If using a 2-pipe system, select “aux” or “no aux” to determine if the system uses an auxiliary heater.
Hit the “Home” button at the top right to return to the thermostat main screen.
Test to ensure the fan coil or heat pump is now reaching the set temperature.
4. Ensure valve actuators are responding to system call
Use a multimeter to confirm that the thermostat is sending a voltage signal (24V AC) to the valve actuator when heating or cooling is called for.
Remove the front plate of the thermostat by gently prying it from the wall-mounted rear plate.
Place one probe on the common terminal (C)
To test call for cool: place the other probe on terminal Y
To test call for heat: place the other probe on terminal W
If a reading of ~24 VAC appears, the thermostat is sending the appropriate system call. If the actuator does not respond, a replacement is needed. If there is no voltage reading, the thermostat may not be wired correctly, or may be faulty. See installation instructions for more details.
Universal Fan Coil Thermostat
2. Ensure the temperature sensor is functioning
The thermostat may have an incorrect temperature reading, forcing the fan coil to turn off before reaching the true set temperature. You can test the accuracy of the thermostat reading by using a thermometer to measure the temperature near the thermostat.
If the temperature does match, the thermostat may be located where sunlight or drafts are impacting the temperature directly around it. Verify by using the same thermometer to measure the temperature of another room that feels similar to the rest of the suite. If the reading is different, the thermostat will need to programmed with a temperature offset. Instructions for setting a temperature offset can be found here.
If the temperature does not match the thermostat’s reading, the thermostat’s temperature sensor may be faulty, and a replacement is needed.
If further troubleshooting is required, please book a service appointment with a qualified HVAC technician to proceed.
Warning: The following troubleshooting steps should only be followed by a certified HVAC technician. If you are a resident, please contact your local HVAC repair service.
3. Verify thermostat is set to correct system mode
a. Hold the [menu] button to enter the advanced settings menu.
b. Once the menu has opened, press the [menu] button again until reaching setting “P02”.
c. There are four systems modes. Use the following chart to determine which mode you require. Then press the [▲] / [▼] buttons to reach that mode.
| 2-Pipe Standard | 2P |
| 4-Pipe Standard | 4P |
| 2-Pipe with Auxiliary Heating | 2H |
| 2-Pipe with Aquastat | 2A |
| 2-Pipe with Auxiliary Heating & Aquastat | 2A |
d. Press [SELECT] to confirm and return to the home screen.
Test the fan coil to ensure the system is now working correctly.
2. Ensure the temperature sensor is functioning
The thermostat may have an incorrect temperature reading, forcing the fan coil to turn off before reaching the true set temperature. You can test the accuracy of the thermostat reading by using a thermometer to measure the temperature near the thermostat.
If the temperature does match, the thermostat may be located where sunlight or drafts are impacting the temperature directly around it. Verify by using the same thermometer to measure the temperature of another room that feels similar to the rest of the suite. If the reading is different, the thermostat will need to programmed with a temperature offset. Instructions for setting a temperature offset can be found here.
If the temperature does not match the thermostat’s reading, the thermostat’s temperature sensor may be faulty, and a replacement is needed.
If further troubleshooting is required, please book a service appointment with a qualified HVAC technician to proceed.
Warning: The following troubleshooting steps should only be followed by a certified HVAC technician. If you are a resident, please contact your local HVAC repair service.
3. Verify thermostat is set to correct system mode
a. Hold the [menu] button to enter the advanced settings menu.
b. Once the menu has opened, press the [menu] button again until reaching setting “P02”.
c. There are four systems modes. Use the following chart to determine which mode you require. Then press the [▲] / [▼] buttons to reach that mode.
| Fan Coil System | Thermostat Mode |
|---|---|
| 2-Pipe Standard | 2P |
| 4-Pipe Standard | 4P |
| 2-Pipe with Auxiliary Heating | 2H |
| 2-Pipe with Aquastat | 2A |
| 2-Pipe with Auxiliary Heating & Aquastat | 2A |
d. Press [SELECT] to confirm and return to the home screen.
Test the fan coil to ensure the system is now working correctly.
4. Ensure valve actuators are responding to system call
Use a multimeter to confirm that the thermostat is sending a voltage signal (24V AC) to the valve actuator when heating or cooling is called for.
Remove the front plate of the thermostat by gently prying it from the wall-mounted rear plate.
Place one probe on the common terminal (C)
To test call for cool: place the other probe on terminal Y
To test call for heat: place the other probe on terminal W
If a reading of ~24 VAC appears, the thermostat is sending the appropriate system call. If the actuator does not respond, a replacement is needed. If there is no voltage reading, the thermostat may not be wired correctly or may be faulty. See installation instructions for more details.
