Multiple Outdoor Units Control - Mitsubishi Electric PAC-IF071B-E Installation Manual

9. Multiple outdoor units control

9.1 Wiring for multiple outdoor units control
To establish a larger system, up to 6 outdoor units of the same model can be con-
nected in one system.
Note:
▪ SUZ-SWM outdoor unit can not be connected.
▪ PUZ-(H)WM outdoor unit can not be connected to PAC-SIF051B-E.
▪ Flow sensor is necessary for PUZ-(H)WM outdoor unit.
▪ PUZ-(H)WM outdoor unit DIP switch settings changed to SW5-5 ON.
9.1.1 Requirements
<Outdoor unit>
(a) Up to 6 units can be connected.
(b) All the outdoor units must be of the same model.
(c) The outdoor units must be connected to sub units.
<FTC: Main unit>
Each sub unit is controlled by the main unit.
(a) The outdoor units must NOT be connected to the main unit.
Make sure that the main unit is powered by independent source.
(b) Wire the main remote controller to TBI.6 1-2 on the main unit.
(c) Wire the electric heater to the main unit.
<FTC: Sub unit>
The hydrobox or PAC-SIF051B-E or main unit is used as a sub unit
(a) Connect each outdoor unit to a sub unit.
(b) The main remote controller must NOT be wired to a sub unit.
9.2 Pipe work
Following is the system example of two outdoor units being connected in one system.
IMPORTANT NOTE
Keep the minimum amount of water required in the space heating circuit according to the number of outdoor units.
Flow temp. thermistor
*1
Return temp. thermistor
Outdoor unit
*1 Refrigerant-water HEX
Outdoor unit (Packaged type)
System 1: Heating/Cooling system
• Install a low loss header (local supply).
• Install booster heater toward the local system, relative to the low loss header.
8
9
7
10
en
13
14
12
15
47
Outdoor unit
<Fig. 9.2.1>
1 4
Heating/
6
Cooling
5
11
Low loss header
(local supply)
<Fig. 9.2.2>
Max. 6 units
Outdoor unit
Max. 6 units
Outdoor unit
Flow temp.
thermistor
Ref. liquid
Return temp.
temp.
thermistor
thermistor
*1
(TH2)
*1 Refrigerant-water HEX
Outdoor unit (Split type)
No. Component
1 Booster heater (local supply)
2 Circulation pump1 (local supply)
3 Flow switch1 (local supply) *2
4 Flow temp. thermistor (THW1)
2
5 Return temp. thermistor (THW2)
6 Sub1 circulation pump1 (local supply)
7 Sub1 flow switch (local supply) *2
8 Sub1 flow temp. thermistor (THW1)
9 Sub1 return temp. thermistor (THW2)
10 Sub1 ref. liquid temp. thermistor (TH2) *1
11 Sub2 circulation pump1 (local supply)
3
12 Sub2 flow switch (local supply) *2
13 Sub2 flow temp. thermistor (THW1)
14 Sub2 return temp. hermistor (THW2)
15 Sub2 ref. liquid temp. thermistor (TH2) *1
*1 When the outdoor unit is split type, TH2 needs to be installed. <Fig. 9.2.1>
*2 For safety protection, it is recommended to install a flow switch.
FTC
FTC (Sub)
(Main)
Main remote
controller
Main
FTC (Sub)
Sub
FTC
(Main)
Main remote
controller
Main
Hydrobox
Hydrobox
Sub
Wiring
Main Sub 1 Sub 2