Daikin vrf with com's issue

[Dean A/C]

Hi guys.

I've been called out recently to some Daikin vrf systems with com's fault "ue".

There is a main centralised controller which is controlling everything.
On the controller it is controlling 3 vrf systems.
System 1 is running fine but the other 2 systems are not working.

All indoors are showing on the I touch main controller but are not able to be turned on or so anything.

Is checked com's between controller and outdoors and getting 16dc v on the com's.
Getting 16dc v to the indoors
But not getting anything on the multi link from one outdoor to the other.

I've tried resetting everything but no joy.

If anyone could help it would be appreciated

Cheers
Dean

[RusBuka]

Search dead MB in indoor unit.

[install monkey]

centralised connects accross outdoor units

[paddyaircon]

dead MB???

[icemakerman]

try Daikin Tech Support , they are very helpful in Australia. Don't know if they have the support in England that we get in Aust.

[pete114]

Try 01275 341030 Daikin uk support. Usually very helpful.

[Asbolute]

Check the F1-F2 terminals labelled OUT on each master VRV system, if you have system 1 with no coms then the cable from central probably goes to this on the correct terminals, from these terminals follow the cable to the next system and then the next but remember if one system has two outdoor units only work on the masters