Indoor Unit Only Operation - Mitsubishi Electric Hydrobox EHSC Series Installation Manual

5
System Set Up
5.3 Wiring for 2-zone temperature control
Connect the pipe work and locally supplied parts according to the relevant circuit
diagram shown "Local system"in Section 3, of this manual.
<Mixing valve>
Connect the signal line to open Port A (hot water inlet port) to TBO. 2-3 (Open), the signal line to open Port B (cold
water inlet port) to TBO. 2-1 (Close) , and the neutral terminal wire to TBO. 2-2 (N).
<Thermistor>
•Do not install the thermistors on the mixing tank.
•Install the Zone2 flow temp. thermistor (THW8) near the mixing valve.
•The maximum length of the thermistor wiring is 30 m.
•The length of the optional thermistors are 5 m. If you need to
splice and extend the wirings, following points must be carried out.
1) Connect the wirings by soldering.
2) Insulate each connecting point against dust and water.
en
5.4 Indoor unit only operation (during installation work)
In the case when DHW or heating operation is required prior to connection of the outdoor unit; i.e. during installation work, an electric heater in indoor unit (*1) can be used.
*1 Model with electric heater only.
1. To start operation
● Check if the indoor unit power supply is OFF, and turn DIP switch 4-4 and 4-5 ON.
● Turn ON the indoor unit power supply.
2. To end operation *2
● Turn OFF the indoor unit power supply.
● Turn DIP switch 4-4 and 4-5 OFF.
*2 When the indoor unit only operation is ended, ensure to check over the settings after outdoor unit is connected.
Note:
Prolonged running of the this operation may affect the life of the electric heater.
21
N L
FTC
1 2 3
TBO.2
Close N Open
to Zone2
from mixing tank
heat emitter
A
Motorized mixing
valve
B
to mixing tank from Zone2
heat emitter