
Optional parts
D-26
HIGH TEMP. THERMISTOR
4
Optional parts
Heat source
Heating
DHW
Heat pump
Boiler
—
a) Heating room temperature (
)
FTC4
Boiler
Outdoor unit
b) Heating flow temperature (
)
c) Heating compensation curve (
)
FTC4
Boiler
Outdoor unit
Wireless remote
controller (option)
or
Room temperature
thermistor (option)
or
Main controller (remote
position)
Room thermostat (field
supply)
or
Wireless remote controller *
(option)
Room thermostat
* Wireless remote controller can be changed to room thermostat.
1.2 Pipe work
(a) Boiler and heat pump are connected in parallel.
(b) Install a mixing tank (field supply).
(c) Put 2 thermistors in boiler circuit. (THWB1: Flow temp., THWB2: Return temp.)
* It is recommended to protect the thermistors with heat insulating materials so as not to be affected by ambient temperature.
Note: These lead wires of the thermistors must avoid being in contact with pipe surfaces.
Boiler
Heating
Mixing tank
(field supply)
Cylinder unit/
Hydrobox
Outdoor unit
1
2
3
4
5
6
Boiler
Heating
Mixing tank
(field supply)
Hydrobox
DHW tank
Outdoor unit
1
2
7
8
9
3
4
5
6
Number
Component
1
Boiler flow temp. thermistor (THWB1)
2
Boiler return temp. thermistor (THWB2)
3
Flow temp. thermistor (THW6) (option)
4
Return temp. thermistor (THW7) (option)
5
Circulation pump (field supply)
6
Flow switch (field supply) *1
*1 For safety protection, it is recommended to install a flow switch.
Number
Component
1
Boiler flow temp. thermistor (THWB1)
2
Boiler return temp. thermistor (THWB2)
3
Flow temp. thermistor (THW6) (option)
4
Return temp. thermistor (THW7) (option)
5
Circulation pump (field supply)
6
Flow switch (field supply) *1
7
Tank water temp. (THW5)
8
Immersion heater (field supply)
9
3-way valve (field supply) *2
*1 For safety protection, it is recommended to install a flow switch.
*2 The use of two 2-way valves can perform the same function as a 3-way
valve.
1. System
1) Heat source can be switched between heat pump and boiler by external input from power supplier or outdoor temperature
thermistor.
2) Heat source can be switched according to running cost, CO
2
emission, or outdoor temp.
3) In case of outdoor unit failure, backup operation is possible with boiler. *1
*1 When Hybrid is selected as heat source.
When Dip SW2-5 (Automatic switch to backup heat source operation) is set to ON.
Note: FTC4 can control boiler only in space heating mode.
1.1 Room thermostat connection
IMPORTANT NOTE
Be sure to connect room thermostat to FTC4.
When boiler is running, the heating operation is regulated by the room thermostat connected to FTC4.
Room thermostat