The Daikin U9 error code basically means a transmission defect, a communication problem between the indoor unit and the outdoor unit. The U9 error can be caused by a faulty evaporator coil, indoor thermistor, and indoor PCB. The initial price of all the said parts is $150, depending on the aircon model you are using.
When your Daikin Aircon light is blinking, you can easily take out a remote control to figure out the Daikin error code. Then, let’s assume that you know how to get the error code of a Daikin Aircon system. Furthermore, you get a Daikin error code U9, what does it mean now? And what should you do? Fret not, here at Silverback Aircon we fix Daikin Aircon units on a daily basis. We will guide you on the meaning of Daikin U9 error code. How to troubleshoot whenever you have this error. We will also provide you with the estimated cost of fixing this issue.
Daikin U9 Error Code refers to the malfunction of transmission. It typically occurs between indoor and outdoor unit. In fact, an indoor unit and outdoor unit communicate by a signal. The signal is usually in waves. The indoor unit will signal to the outdoor unit to work harder and hence the Aircon will be colder. Whenever there is a malfunction of transmission, it means that the signal has an issue. As a result, the indoor and outdoor unit will not be able to communicate properly.
So whenever you have a Daikin error code U9, you can think of it as a malfunction of communication. Do note that U9 error code and U4 error code is also very similar. However, U4 error code can occur in the outdoor unit as well. As it is referring to a malfunction of transmission between indoor and outdoor unit. Where as U9 refers to malfunction of transmission in other system.
Contrary to popular belief. U9 error code is not difficult to troubleshoot. In fact it is even more simple to troubleshoot than that of U4 error code. The first step in troubleshooting this error code is check for loose F1/F2 connections. When the connection point is loose, the signal will not be able to properly communicate. Sometimes you will be surprise at such a simple solution to the problem. Other than loose F1/F2 connections, you should also check on the door PCB and indoor electronic expansion valve. However, most fan coil units don’t have expansion valve. So this is referring more to chilled water fan coil units and VRV system.
As mentioned in the troubleshooting procedure above. The solution involves tightening the connection point. If not check whether the expansion valve is working or not. If the expansion valve is not working ,it is most likely a case of indoor PCB failure. Do note that if the above solutions does not fix your problem. It can also be a case of multiple parts failure. Do check for the incoming power supply to the FCU as well.
These are the estimated cost of fixing Daikin U9 error code. However do note that this list is only applicable for DX units. For chilled water or VRV units, the price will be very different. Here at Silverback Aircon, we sell refurbished Daikin Aircon spare parts that can help you solve your U9 error code issue. Do note that we do not sell VRV or chilled water parts.
I hope this post gives you an idea of how much it costs to fix the this error code. In addition, has help you comprehend the U4 error code. Silverback Aircon specialize in Daikin Aircon repair for residential units only. While it is relatively simple to diagnose U9 error code, it may be best to leave it to trained technicians to figure out the issue. Do let us know if you have any Daikin repair problems. For more on Daikin aircon error codes and their respective solutions, refer to our “Daikin Error Codes and How Much It Costs To Fix” expert guide article.
