Toshiba HWT-602S21SM3W-E(TR) Service Manual page 90

Item
7-3. 7) Room temperature control with the thermostat
Hydro Unit Control
You can install a commercially available thermostat to control room temperature.
7-1) Installing the room temperature thermostat
• Connect its connection cable to CN21 port on the PC board (MCC-1755) of the hydro unit.
• Thermostat for heating: Connect the input between the terminals (1) and (5).
Thermostat for cooling: Connect the input between the terminals (2) and (5).
• Place to install (inside a room): At the height of 120 cm - 180 cm on a wall
Opposite to the radiator or fan coil installed
No assignment when floor heating is used on the room.
Optional inputs to Hydro Unit
This unit has eight input ports. 2 ports of them are selectable by DN. Table2 shows the selectable input functions and
default settings.
Non-voltage contacts
MCC-1755
common
line
common
line
Hydro Unit sub PCB
7-2) Room temperature thermostat control setting
• Setting of DN_6B3 = "1" (Default "0")
I/P1 & I/P2: Room thermostat input
• Setting of DN_6B3 = "1"
• Non-voltage contacts
Thermostat operation
CN21
1-5 (I/P1)
2-5 (I/P2)
7-3)Heating thermostat operation
When the heating thermostat does not reach the assigned temperature (the circuit between (1) and (5) is closed),
heating starts under the setting that water temperature for heating is 40°C (DN_9D). If the heating thermostat has
not reached the assigned temperature 30 minutes after heating had started, the water temperature setting is turned
up 1 degree, and the same action will be repeated every 30 minutes until the thermostat reaches the assigned
temperature. The backup heater and booster heater are controlled in the same way as in the normal HP operation.
When the heating thermostat reaches the assigned temperature (the circuit between (1) and (5) is open), the heat
pump shifts to the "thermostat off" operation. During the operation, the water temperature setting is turned down
by 1 degree every 30 minutes. The backup heater and booster heater are tuned off as the heat pump shifts to the
"thermostat off" operation.
Operation flow and applicable data, etc.
CN21 CN21
1
2
3
I/P 3
4
I/P4
5
6
7
8
I/P 7
9
I/P 8
10
Locally procured
Heating
Reach Not reach Reach
open close
- - close
89
I/P 1
I/P 1
I/P 2
I/P 2
I/P 3
I/P 4
I/P 5
I/P 6
I/P 5
I/P 6
I/P 7 (DN_B6) 0: Emergency shutdown input
I/P 8 (DN_B6) 0: None
Cooling
Not reach
- -
open
Input items (Default setting)
Room thermostat input for heating
Room thermostat input for cooling
Hot water tank thermostat input
Heating/cooling mode switching input
Heating/cooling operation ON/OFF
Hot water operation ON/OFF