A.O. Smith GPD-40 Instruction Manual page 16

to the connector on the bottom side of the gas control valve/
thermostat.
6. If the wiring harness is not factory installed, make sure the ON/
OFF switch is in the OFF position and then connect the wiring
harness from the blower control box to the connector on the
bottom side of the gas control valve/thermostat.
7. This water heater is a polarity sensitive appliance and will not
operate if the power supply polarity is reversed. The power supply
WIRING SCHEMATIC
DIAGRAM 1.
or outlet providing power to this water heater must be wired
properly (correct polarity).
8. Do not plug in power cord until vent system is completely installed.
This power direct vent heater operates on 110-120 Vac, therefore
a grounded outlet must be within reach of the six (6) foot (1.8 m)
fl exible power cord supplied with the unit. See Figure 2. The power
cord supplied may be used only where local codes permit. If local
codes do not permit the use of a fl exible power supply cord:
a.) Make sure the unit is unplugged from wall outlet. Remove
screws and remove control box.
b.) Cut the fl exible power cord, leaving enough to be able to make
connections, the remove the strain relief fi tting from box.
c.) Install suitable conduit fi tting in side of enclosure and then
follow (d.) and (e.) below.
d.) Splice fi eld wiring into existing wiring using code authorized
method (wire nuts, etc.).
e.) Be certain that neutral and live connections are not reversed
when making these connections.
f.) Replace control box, make sure that the control box is secured
shut.
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