34
Equipment must be grounded.
All high-voltage external load, if it is metal or a grounded port, must be grounded.
All external load current is needed less than 0.2A, if the single load current is greater than 0.2A, the load must be controlled
through AC contactor.
AHS1" "AHS2", "A1" "A2", "R1" "R1" and "DTF1" "DTF2" wiring terminal ports provide only the switch signal.
Please refer to image of 9.7.6 to get the ports position in the unit.
Expansion valve E-Heating tape,Plate heat exchanger E-Heating tape and Flow switch E-Heating tape share a control port.
Please use H07RN-F for the power wire, all the cable are connected to high voltage except for thermistor cable and
cable for user interface.
NOTE
Field wiring guidelines
Most field wiring on the unit is to be made on the terminal block inside the switch box. To gain access to the terminal block,
remove the switch box service panel .
9.7.3 Precautions on wiring of power supply
Use the correct screwdriver to tighten the terminal screws. Small screwdrivers can damage the screw head and prevent
appropriate tightening.
Over-tightening the terminal screws can damage the screws.
Attach a ground fault circuit interrupter and fuse to the power supply line.
In wiring, make certain that prescribed wires are used, carry out complete connections, and fix the wires so that outside force
cannot affect the terminals.
Use a round crimp-style terminal for connection to the power supply terminal board. In case it cannot be used due to unavoid-
able reasons, be sure to observe the following instructions.
Do not connect different gauge wires to the same power supply terminal. (Loose connections may cause overheating.)
When connecting wires of the same gauge, connect them according to the figure below.
-
-
Switch off all power including the unit power supply and backup heater and domestic hot water tank power supply (if
applicable) before removing the switch box service panel.
WARNING
Fix all cables using cable ties.
A dedicated power circuit is required for the backup heater.
Installations equipped with a domestic hot water tank (field supply) require a dedicated power circuit for the booster heater.
Please refer to the domestic hot water tank Installation & Owner's Manual. Secure the wiring in the order shown below.
Lay out the electrical wiring so that the front cover does not rise up when doing wiring work and attach the front cover securely.
Follow the electric wiring diagram for electrical wiring works (the electric wiring diagrams are located on the rear side of door 2.
Install the wires and fix the cover firmly so that the cover may be fit in properly.
7
6
1
3
2
4
5
1
2
3
4
5
High voltage wire hole
Low voltage wire hole
High voltage or low voltage wire hole
Water outlet
Water inlet
Assembly unit
Coding
6
Drain outlet
7
Drainage pipe hole (for safety valve)
V.2
Summary of Contents for ETH220VMA
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