1 out of 5 working

[peapod]

Hi all
I have 5 hitachi RAS 4HG7E cond units and 5 RC1 4HG7E cass units in one office area all controlled by one controller, the 1st unit off the controller works in all mode's but only the fan's run on the other 4,All 5 work in test mode heating and cooling spoke to hitachi checked cable / changed controller and setting's still 4 non running's.
Any ideas
cheers
peapod

[monkey spanners]

I'd be looking at the dip switch settings on all the units and the controller to make sure they are set for group control and are addressed correctly.

[Brian_UK]

Have they worked in the past or is this a new install?

[peapod]

hi brian/monkey spanners
The install is about 4 years old but i have not seen it run only been call to it a few days ago(new staff have just moved in so no history of the system) ,i have checked and changed the address but with no luck , I didn't see any dip switches for group setting.
I will be going back on monday so i will double check for the dip switches
cheers
peapod

[monkey spanners]

I don't fit Hitachi stuff often so am not really familiar with it. I usually phone the manufacturers technical people with problems like this, if they know there stuff they will be able to point you in the right direction.

[peapod]

Hi all
Went back yesterday i had disconnected the system from the site BMS system last week(at the BMS station) but after speaking to hitachi yesterday they said to diconnect the bms plugs on the indoor pcb, it work's now
thanks for your help
pea pod

[Brian_UK]

There you go, it's easy when someone knows how.

Thanks for the update.

[andy c]

Hitachi's don't wanna work in cooling at ambient below -7 / -5 oC. They have dip settings on the outdoor pcb to override the ambient sensor, i think it's dsw1, switch 2, but would need to check. It's not something they advertise. The controller shows no fault, but the condensing unit won't run.

The unit addresses are set at the controller, and need to be changed if an indoor board is replaced. Or maybe they were never set up when installed. Daikin Tech will advise if necessary, it is easy to do, i have it written down somewhere, if you get stuck.