Fan coil fault or system problem?
A fan coil does not produce cooling or heating on its own; it takes its energy from the water in the pipes. So the first question is: is the problem in a single fan coil, or on the whole floor or building? If cooling is weak throughout the building, the problem is most likely on the chiller, pump or boiler side. If the problem is in a single unit, the fan coil itself is checked. We explained how a fan coil works in our article what is a fan coil.
Fan coil faults by symptom
| Symptom | Likely causes | First check |
|---|---|---|
| Fan coil not cooling | Dirty filter or coil, closed/faulty valve, actuator failure, line not bled of air, no water coming from the chiller | Thermostat mode and set point, filter condition, whether other rooms are cooling |
| Fan coil not heating | 2-pipe system still in summer mode, no hot water from the boiler, valve not opening, or air in the line | Has the seasonal changeover been done, is the thermostat on heating |
| Leaking water, stain on the ceiling | Blocked drain pan or line, drain pump failure, condensation on uninsulated valves and pipes | Turn off the unit, protect the ceiling; the drain line must be cleared |
| Fan not running | Fan motor or capacitor failure, thermostat output, fuse/terminal block problem | Change the thermostat fan speed, check the fuse |
| Noise or vibration | Dirty or unbalanced fan wheel, loose connection, bearing wear | Does the noise change with fan speed |
| Bad odor | Standing water in the drain pan, dirty coil or filter | Filter and pan cleaning |
| Thermostat display blank / no response | No power supply, wiring connection, thermostat failure | Fuse and power supply |
Technical support for a fan coil fault
Tell us the symptom, unit type and quantity; if needed, we will dispatch a team on the same day (Ankara).
Fan coil not cooling: step-by-step check
- Is the thermostat in cooling mode with the set point below the room temperature?
- Is the fan running and blowing air? If the airflow is weak, the filter may be clogged.
- Are the pipe or valve body going to the fan coil cold? If not cold, the valve is not opening or no water is arriving.
- Are the fan coils in other rooms cooling? If none are cooling, the chiller and pump side should be checked.
These checks can be done safely by the user. Removing valves, electrical connections and bleeding air from the line are jobs for the technical team.
What should you do if the fan coil is leaking water?
A leaking fan coil can damage the suspended ceiling, the electrical installation and belongings. First turn off the unit at the thermostat and protect the area below it. The most common cause is a blocked drain pan or line; in units with a drain pump, a pump or float failure can also be the cause. If valves and pipes lack insulation, condensation forms on them too. Regular fan coil maintenance is the most effective way to prevent this.
Fan coil fault codes
Most classic fan coils do not have a display that shows fault codes; codes are usually seen on digital thermostats or the manufacturer's control boards. The meaning of codes varies by brand and thermostat model; for a correct interpretation, refer to the manual of the unit or thermostat. We covered thermostat issues separately in fan coil thermostat and motor failures in fan coil motor.
Frequently asked questions
Why does a fan coil not cool?
The most common causes are a dirty filter or coil, a valve or actuator that does not open, air trapped in the line, and no cold water coming from the chiller.
Why does a fan coil drip water?
Most often the drain pan or line is blocked. A drain pump failure and condensation on uninsulated valves and pipes can also cause water leaks.
What should I do if the fan coil is not heating?
In 2-pipe systems, first make sure the seasonal changeover has been done and the thermostat is in heating mode. If the problem continues, the valve, air and boiler side should be checked.
The fan coil fan is not running, what could be the cause?
It may be a fan motor or capacitor failure, a thermostat output problem or a power supply problem. Electrical measurements should be carried out by the technical team.
How soon does service arrive for a fan coil fault?
In Ankara we respond to fault calls on the same day. In other provinces we work with a planned team or under a maintenance contract.