Mitsubishi Heavy Industries SRR25ZS-W Service Manual Download

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'20 • SR-SM-285

(17) Plural unit control – Control of 16 units group by one remote control

(a) Function

One remote control can control a group of multiple number of unit (Max. 16 indoor units). “Operation mode” which
is set by the remote control can operate or stop all units in the group one after another in the order of unit. No.

(1)

Thermostat and protective function of each unit function independently.

Note (1) Unit No. is set by SW2 on the indoor control PCB. Unit No. setting by SW2 is necessary for the indoor unit only.

SW2: For setting of 0 – 9, A – F

(2) Unit No. may be set at random unless duplicated, it should be better to set orderly like 0, 1, 2…, F to avoid mistake.

(b) Display to the remote control

(i) Central or each remote control basis, heating preparation: the smallest unit No. among the operating units in the

remote mode (or the center mode unless the remote mode is available) is displayed.

(ii) Inspection display, filter sign: Any of unit that starts initially is displayed.

(c) Confirmation of connected units

(i) In case of RC-EX3A remote control

If you touch the buttons in the order of “Menu” → “Service setting” → “Service & Maintenance” → “Service
password” → “IU address”

on the TOP screen of remote control, the indoor units which are connected are displayed.

(ii) In case of RC-E5 remote control

Pressing “AIR CON No.” button on the remote control displays the indoor unit address. If “▲” “▼” button is
pressed at the next, it is displayed orderly starting from the unit of smallest No..

(d) In case of anomaly

If any anomaly occurs on a unit in a group (a protective function operates), that unit stops with the anomalous stop but
any other normal units continue to run as they are.

(e) Signal wiring procedure

Signal wiring between indoor and outdoor units should be made on each unit same as the normal wiring. For the group
control, connect the remote control wiring to each indoor unit via terminal block for the remote control.

Connect the remote control wiring separately from the power source cable or wires of other electric devices (AC220V
or higher).

(18) High ceiling control

When sufficient air flow rate cannot be obtained from the indoor unit which is installed at a room with high ceiling, the air

flow rate can be increased by changing the fan tap. To change the fan tap, use the indoor unit function “FAN SPEED SET”

on the wired remote control.

P-Hi1 - Hi

P-Hi1 - Me

STANDARD
HIGH SPEED1

FAN SPEED SET

Hi - Lo Hi - Me

P-Hi1 - P-Hi1 - Hi - Me

P-Hi1 - Hi - Me - Lo

Indoor unit air

flow rate setting

Fan tap

P-Hi1 - Hi - Me

Hi - Me - Lo

Notes (1) Factory default is STANDARD.
(2) At the hot-start and heating thermostat OFF, or other, the indoor fan is operated at the low speed tap of each setting.
(3) This function is not able to be set with wireless remote controls or simple remote control (RCH-E3).

Remote control

Indoor unit

Outdoor unit

Signal wiring

between outdoor unit

and indoor units

Remote control wiring

Refrigerant piping