Alarm Code "31 - Hitachi RPI-0.8FSG1 Service Manual

FIELD WORK INSTRUCTION
5.4

Alarm Code "31"

Question and Answer for Field Work
Example 4:
[Phenomenon]
Alarm code "31" sometimes occurred and the system was stopped.
[Cause]
Combination of the indoor and outdoor unit was as follows.
ON
This system was used in a tenant building.
One of tenant's customers cut out the power switch for the indoor unit while other indoor units are
running, resulting in different total indoor unit capacity setting in the same refrigerant cycle.
[Countermeasure]
All the main power switches for the indoor units were always ON.
5-4
Alarm Code "31"
ON
OFF
I.U. I.U.
ON ON
I.U.
ON
I.U.
O.U.