Hi there,

I am currently having some issues with controlling a Hitachi RCI split through a HC-A32MB MODBUS interface. I am receiving communications from the device and can make setpoint changes etc. but when reading from the registers I only get the “SET” and nothing from “STATUS.”

There is a constant error 61 coming back from the device which I believe means a loss of communication from the indoor unit, but this isn’t actually happening as I can see the supply and return air temperatures updating in realtime, plus I can make setpoint changes instantly!

The controls cables are all shielded and not running near to any power lines so any interference is highly unlikely.

Has anyone had a similar problem before and could possibly point me in the right direction?

Apologies if this isn't the right location for this post.

Many thanks,

Jordan.