Daikin J6 Error After Thermistor & PCB Replacement (REYQ10PY1B)

[JB300]

Hi all,

First post on here, so, hello!

First and foremost, full disclosure: I'm not an engineer. I have followed the service manual and called Daikin support for guidance. A senior support engineer will be calling back today, but I thought I'd ask the question here in the meantime and provide the information for anyone else facing the same issue.

As the title suggests, we had a J6 error show on the controllers (BRC1D52). We have one outside unit (REYQ10PY1B) connected to 4 indoor units (not sure about the model number).

As per the service manual, we changed the thermistors in the outside unit connected to the X30A port on the A1P board. After this, we restarted the system in the proper order (indoor off, outdoor off, indoor on, outdoor on). The J6 error remained. Then we replaced the A1P PCB and restarted. The J6 error remains. We have also tried the reset procedure by restarting the system, holding the reset button, and leaving the system switched off overnight, but the issue is still present. When looking at the LEDs on the outside unit, the H8P and SERVICE MON lights are flashing. When trying to run a Short Wiring & Piping Check (following the Daikin Service App), nothing happens after completing the procedure to start the check. I assume it is stopped due to the J6 error.


We have tested the resistance of the thermistors and give the correct reading (1.8Kohms - 800Kohms).

Has anyone else had this issue or can see anything that we've missed? Pending the phone call from Daikin, our next thought is that a board on the other side of the unit has some memory that has stored the error, or that the controllers are storing the error.

Any help to point us in the right direction would be really appreciated.

Thanks,
Joe

[JB300]

We've just found the issue.

Our unit is a split unit and we were working on the slave side instead of the master without knowing there was a master side.

Lesson learnt! When asking for information and guidance, make sure that you are working on the correct unit to start off with. Or better yet, get the engineer on the phone to walk you through it, step by step, without skipping anything.

Cheers,
Joe