Specifications

A. O. Smith Water Products Service Handbook

Ashland City, Tennessee 2005

Training Department

GENESIS POWER VENT WIRING DIAGRAM

Electrical power to the power venter must be supplied by the installer and wired according to the Wiring

Diagram. Wiring must comply with the wiring diagram in order for the boiler to function properly. The

wiring is part of the boiler's safety circuit and shuts off the boiler if the Fan Proving Switch at the power

venter is not made.

The Genesis II Control System is also set to shut off the power venter when there is no "call for heat".

A normal condition for the boiler's Display Board is for the Power Venter Red LED to remain lit while the

unit is in a Standby mode. Awaiting another "call for heat". Once a "call for heat" is generated, the

Control System will start a Firing sequence by starting all of the

blowers inside the unit and at the same

time send a 24 VAC signal and a 24 VAC return (terminals 7 & 6 of the Genesis II External 24 VAC

Distribution Box) to the power venter to turn its fan motor on utilizing relay R1 at the Power Venter

Electrical Box. Once the Power Venter fan gets up to speed and makes the fan proving switch, the 24

VAC signal is routed back to the boiler and can be measured between terminals 5 and 6 at the Genesis

II External 24 VAC Distribution Box. The returning 24 VAC signal will then extinguish the previously lit

Red LED and the unit will continue its Normal Pre-purge mode and then light the boiler.

Any failure will shutoff the boiler and the power venter off after the Post-purge Cycle

is completed. The

failure that caused the shut down will be displayed at the Display Board and a Lockout message and

error code will be displayed. Remember that when the Power venter is not running, the Red LED

indicator for the Power Venter will also be displayed; so troubleshoot the other indicators first before

suspecting the Power Venter. If the cause of the failure is the Power Venter, then the only Red LED lit

will be its own and the Display Message will be "Lock-Out 070" ---the error code for a Power Venter

Failure.