Watts LFWDS - Manual (Page 3)

3. Install the incoming supply power to the normally open contacts of the relay as shown in the wiring diagram Figure 7 and Figure 8.
Be certain to connect a ground wire to the relay enclosure, as shown in Figure 7.
4. Connect the power cable to the water heater to the common terminals of the relay, as shown in the wiring diagram Figure 7.
5. Install the spade terminals on the connecting cable and connecting cable to the relay terminals R1 and R2. Route the connecting
cable to the Control Unit and insert the interlocking connector end to the circuit board.
6. Remove the green circuit board terminal strip from the Control Unit by pulling straight out on the terminal strip. Figure 9
7. Install wiring (The wire is installer supplied. Thermostat wire is acceptable) between the green circuit board connector and the
Power Supply, observing polarity, as shown on both the power module and the control panel. [+ to + and – to -] Figure 10
Maximum run of thermostat wire; 18 gauge – 75 feet; 20 gauge – 50 feet;22 gauge – 35 feet.
Note: If remote alarm detection is desired, connection to the alarm circuit can be made using the normally open contacts provided on
the terminal strip. These contacts are rated for 150mA. Do not exceed this amp range or damage to the Control Unit can occur.
Exceeding the current rating will void the warranty. Figure 11
IMPORTANT! – Do not insert the power supply into the 120 VAC outlet until the installation is complete.
8. Insert the green circuit board connector into the Control Unit. Figure 12
9. Check the position of the valve reset located on the front of the Control Unit. The slots should indicate the valve is in the open
position. The 11 o’clock position is the open position. Figure 13 open position; Figure 14 closed position.
Continued…
Figure 9 Figure 10 Figure 11
Figure 12 Figure 14 Figure 15
3
NO
NO
C
C
R1
R2
L2 L1 GROUND
GROUND
L2
L1
DIAGRAM 1
RELAY ENCLOSURE
RELAY
RELAY ENCLOSURE
GROUND TERMINAL
WATER HEATER
POWER SOURCE
TO WATER
HEATER
TO
CONTROL
UNIT
Figure 7
Figure 8
R2
R1
L1
L2
L1
L2
To
Water
Heater
From
Supply
Power