Disable failed Daikin FXSQ100 affecting rest of the system

Hi all,

I have just come back home with my new baby (born Monday!) and came to find a power surge has killed various things on one of the house's phases (220V). Part of this has been a blown fuse in a swing indoor unit, plus the transformer on an FXSQ indoor unit (220V to 25V).

I have three ducted indoor units, so I took the transformer from an operating one and made sure the PCB on the failed one works. So far so good.

What I now find is that all the remotes around the house show the U04 fault, and the outdoor unit doesn't operate. From what I understand, the indoor units are "chained" via the F1/F2 connections, and so if one fails the rest also stop operating.

What's strange is that the failed unit was not working, but the rest of the units around the house were fine, so my questions are:

1. Can I isolate one of the units in the middle of the chain? If so, how? Remove the F1/F2 cables & join them away from the unit?

2. If #1 is possible, anything that needs to be done elsewhere? Remote controls, outdoor unit...

3. Failing the above, any other ideas?

We're at 35ºC and 80% humidity, and the baby is really suffering (we can handle it in the pool...)

Thanks!

You dont say what the outdoor model is but I suspect it will be a mini VRV.
turn off local power to the failed indoor unit, leave all wiring in place and then press and hold the Reset button on the outdoor pcb, it is just below the Yellow leds.
the reset should take about 15 minutes then the system should work.
once you have repaired the failed indoor fan coil, you will need to do a further reset to get the fan coil addressed again with the outdoor unit

Thanks for the input - I managed to figure it out by looking at a lengthy troubleshooting guide, where it mentioned the need to reset the system after adding/removing units. The operating ones are all working fine, and I'm sourcing the transformer.

BTW it's a tower VRV III.