14 Generac®PowerSystems, Inc.
RETRANSFER AND SHUTDOWN
When utility power source voltage has been restored,
electrical loads may be transferred back to that source
and the generator can be shut down as follows:
• Verify that utility power supply voltage to the transfer
switch has been positively turned “Off,” using what-
ever means provided (such as utility main line circuit
breaker).
• Set the generator’s main circuit breaker to its “Off ” or
“Open” position.
• Let the generator engine run at no -load for a few min-
utes, to stabilize internal unit temperatures.
• On the generator console, set the Auto-Off-Manual
switch to “Off”. Wait for engine to come to a com-
plete stop.
• For transfer to utility position, refer to the Owner’s
Manual of your particular transfer switch.
• Turn on the utility power supply to the transfer
switch, using whatever means provided (such as a
utility main line circuit breaker). The utility power
source now powers the loads.
AUTOMATIC OPERATION
Toset the system for fully automatic operation, proceed
as follows:
• Check that load circuits are connected to the
utility power supply.
• Set the Auto/Off/Manual switch to its “Auto” position.
• Set the generator main circuit breaker to its “On” or
“Closed” position.
WEEKLY EXERCISE CYCLE
The generator will start and exercise once every 7 days.
During this weekly exercise, the unit runs for about 20
minutes and shuts down. Transfer of loads to genera-
tor output does not occur during the exercise.
To select day and time for exercising, proceed as
follows:
• Set the Auto/Off/Manual switch to OFF.
• Set generator main circuit breaker to OFF or OPEN.
• Locate the rocker switch on the control panel identi-
fied with the words “Set Exercise Time” (Figure 9).
• Push “Set Exercise Time” switch to ON position for
20 to 30 seconds and then release. Switch will spring
back into its original position when released.
• Wait 30 seconds before setting the Auto/Off/Manual
switch to “AUTO”position.
CAUTION: If you switch the Auto/Off/Manual
switch too soon, the engine may start. If engine
does start, it will shut down automatically in
about two (2) minutes.
• Set the generator main circuit breaker to its ON or
CLOSED position.
• Generator is now programmed to start and exercise
every 7 days thereafter, on day and time of day the
switch was actuated.
• Place a sign on the generator control panel and the
transfer switch, indicating the day and time the
generator will be exercising.
NOTE:
If battery terminals are disconnected or control
panel fuse is removed, the exercise timer needs to
be reset for correct automatic exercise operation.

Figure 9 - “Set Exercise” Switch

ENGINE HEATER
YourGenerac standby generator comes equipped with a
block heater (Figure 10), similar to the block heaters
used in automotive applications.

Figure 10 - Engine Block Heater

Referto applicable wiring diagram(s) and electrical schematic(s) at

back of manual forwir ing connections. Customer supplies a 120V

15A Utility fed circuit for the blockheater.

Section 3 — Operation
Guardian Liquid-cooled 10 kW,15 kW, 20 kW and 25 kW Generators