House Batteries - Jayco SENECA Owner's Manual

SECTION 5
ELECTRICAL SYSTEM – 50 AMP
Always wear eye
working with batteries. Keep sparks,
cigarettes and flames away from the
battery as the battery may explode. Do not
use a booster battery or any other power
source that has an output that exceeds 12-
volt. Use adequate
charging or using the battery in an
enclosed space.
H B
OUSE ATTERIES
Your motor home has many 12-volt DC loads.
When combined, their total load requires
more power than the converter can produce.
High demands for 12-volt power can be met
by the house batteries for a limited period of
time. The 12-volt DC electrical system is
designed for usage with Group 27 deep cycle
batteries. The batteries for the house section
of the motorhome are usually referred to as
house (or coach) batteries.
The house batteries are factory-installed to
provide temporary 12-volt power when 120-
volt power is not available to operate the
power converter. When drawing energy from
the batteries, remember that there is a limited
amount of power
batteries need to be recharged.
To recharge the house batteries
When the engine is running, the alternator will
automatically charge the house batteries
through the auxiliary start solenoid. When
parked at a campsite and plugged into shore
power the power converter will automatically
charge the batteries. Complete charging may
take several hours and depends upon battery
condition and the amount of power consumed
by the 12-volt devices operated during the
charging period.
Dry camping
Consider the charge condition of the house
batteries when dry camping. When the house
batteries are not being recharged and power
is being drawn from them, they will eventually
discharge. A battery will discharge faster as
its voltage gets lower. Plan your 12-volt
electrical use accordingly.
5 - 6
protection when
ventilation when
available before the
A fully charged 12-volt battery will read 12.7
volts DC and have a specific gravity of 1.265
at 80°F (32°C). The house batteries are
considered discharged at 11.8 volts and
"dead" at 11.65 volts.
When battery voltage drops below these
lower thresholds permanent battery damage
may occur.
Typically, a deep cycle battery has an amp-
hour rating of 75-100 amps. If you run the
furnace and refrigerator simultaneously, you
will be using approximately (12.0 + 3.0) 15.0
amps per hour. This does not include any 12-
volt lights, water pump or any other 12-volt
component.
If the furnace and refrigerator in the
above example operated constantly, a
75 amp-hour battery would become fully
discharged in 5 hours (75ah / 15a = 5h).
Battery storage instructions
Some equipment in your motor home will
draw small amounts of electrical current even
when turned "off". To prevent house battery
discharge when the motor home is not
connected to power through the shore power
cord, it is recommended you shut "off" the 12-
volt battery disconnect
disconnect the battery negative cable at the

house batteries.

During storage, it is important to check battery
voltage at least every two weeks and to
recharge them as needed. If you remove the
batteries from your motor home protect them
from accidental shorting and keep them in a
cool, dry, well ventilated area.
Replacement and maintenance
For accuracy, test battery voltage using a volt-
ohm meter (customer supplied). When it is
time to replace the house batteries, replace
with Group 27 deep cycle batteries only.
Contact the battery manufacturer for further
information. Do not reverse the positive and
negative battery cables. Doing so will blow the
reverse polarity fuses that protect the power
converter.
solenoid and