Need help on HITACHI VRF RAS10FSG-38

[cool#9]

Hi everyone.
One of my customers have an R407C HITACHI VRF RAS10FSG-38 with 5x RPI0.8, 1x RPI1.0 and 2x RPI1.5.
We need to put a new unit sized 0.8 with a refnet and a wired remote control, ducted type also.
Today i asked to my local HITACHI supplier who said it's possible to add a new unit R410A ...the old ones are out of stock.
I'm not so familiar with HITACHI aircond, we work at 80% with DAIKIN...
Does anyone have any experience about it ???
Thanks in advance.
Regards
cool#9

[Inverter man]

Hello#9

Your Hitachi dealer is correct, you have a total capacity of 8HP connected to your 10 HP outdoor unit, the design maximum is 13Hp (max index is 130%) therefore it is not a problem to add an additional 0.8 HP. The 410A indoor units are reverse compatible with 407C units as they share the same comms compatability (in fact they were designed to be used for the 407C and 410A outdoor units). So there shouldn't be a problem. The only thing I can't help you on is where you need to install the branch pipe (lack of knowledge), so it's best to seek expert advice from Hitachi or their distributor (they use Hi- tool software) as I've witnessed **** ups on a branch pipe installation which caused repeated compressor burnouts.

Hoping this helps, let us know how you get on.