Daikin VRV

[bobjob]

Hi everyone

I hope someone can help me out with this problem I have with an old Daikin VRV111 system.
The first visit to the site resulted in a replacement of the AP1 main board due to no output on F1-F2, no 15vDC going out of the unit.
The PCB was replaced and the system run up all OK with no problems, as this was about 6months ago in the Summer and I can remember that it was mainly running on cooling for the 2-3 days I was on site.
A service call last week to the unit shows that it is failing on faults U7 and sometimes on fault UA . On investigation there is no output from the replaced AP1 PCB, to the another board on the unit in the next module (AP2) on the comms line Q1-Q2.

It looks like that the replaced PCB as again failed, anyone have any ideas or had this problem before ?

Daikin are no real help and all the setting on the replaced PCB were all set correctly,

BTW this VRV may not have been working for some time as the building was unoccupied for a few months after the initial start up.

thanks Bob

[frank]

U7 - lost communication with multi outdoor units Q1 Q2
UA - Incorrect dip switch settings on replacement PCB or too many/few indoor units attached.

I would double check the dip switch settings and for abnormalities in the comms wiring as a first exercise

[subcoolfm]

Id double check all wiring.
check all phases are there (i HAve had a vrv run on 2 phases and do all sorts of crazy stuff)
Check voltage in, voltage filter pcb, etc etc and follow it onto pcb,
Any other pcbs n site you can pinch?

[Northy303]

Also check your bs box wiring and pcb

[Asbolute]

Hi everyone

I hope someone can help me out with this problem I have with an old Daikin VRV111 system.
The first visit to the site resulted in a replacement of the AP1 main board due to no output on F1-F2, no 15vDC going out of the unit.
The PCB was replaced and the system run up all OK with no problems, as this was about 6months ago in the Summer and I can remember that it was mainly running on cooling for the 2-3 days I was on site.
A service call last week to the unit shows that it is failing on faults U7 and sometimes on fault UA . On investigation there is no output from the replaced AP1 PCB, to the another board on the unit in the next module (AP2) on the comms line Q1-Q2.

It looks like that the replaced PCB as again failed, anyone have any ideas or had this problem before ?

Daikin are no real help and all the setting on the replaced PCB were all set correctly,

BTW this VRV may not have been working for some time as the building was unoccupied for a few months after the initial start up.

thanks Bob

What are the outdoor model numbers?
Do you have the correct replacement PCB for REMQ's
Is it set correctly for the HP?
What is the total index of your indoor units?