Battery (Maintenance Free); Battery Amp Draw And Testing; Battery Cleaning; Battery Storage - Airstream TOMMY BAHAMA 2017 Owner's Manual

Maintenance

Battery (Maintenance Free)

Your Airstream Touring Coach is factory-equipped with
a 12V, deep cycle AGM GPL-24T Lifeline battery�

Battery Amp Draw and Testing

For example, a battery with a 100 amp-hour capacity
can deliver 1 amp for 100 hours or it can deliver 100
amps for one hour� Batteries are able to deliver current
longer if they are discharged at a lower rate and deliver
less current at a higher discharge rate�
All batteries will have an Amp Hour (AH) rating� The
AH rating on a battery is its C/20 rate or 20 hour
discharge rate� As long as a battery is discharged over
a 20 hour or longer period, it will deliver 100% of its
rated capacity� If it is discharged in less time at higher
currents it will deliver less capacity�
When testing the touring coach's battery the battery
needs to be at least 75% charged� You can use a
hydrometer reading to verify the state of charge� Once
the battery is above 75% charged a load test can be
performed�
For proper load testing the battery needs to be fully
charge and the voltage should be greater than 12�8
volts� A typical load test should be 3 times the amp
hour for 15 seconds� At the end of 15 seconds the
voltage of the battery should stay above 9�6 volts� If the
battery cannot reach a fully charged voltage of 12�8 or
greater the batteries will need to be equalized�
NOTE
When checking the state of charge the battery
needs to have been disconnected from a charging
source and any loads for a minimum of four hours.
The following chart shows the approximate % of
charge SOC (State of charge) vs� OCV (Open circuit
voltage) and specific gravity for Interstate batteries.
9-6

Battery Cleaning

Battery maintenance is an important issue� Maintain a
clean battery top and check terminals and cables for
tightness and cleanliness� A dirty battery will dissipate
its charge through surface contamination� Clean the
battery top with a damp cloth and dry thoroughly�
To ensure maximum battery capacity on the charge
and discharge, the battery terminals and the inside
portion of the cable connector should be scraped
or brushed� The terminals should be tight and free
of corrosion� The battery should be cleaned using
a baking soda and water mix, with a ratio of two
tablespoons of baking soda to a pint of water� The
cable connection should be cleaned and tightened
regularly�
For battery service or replacement, go to any service
station or dealer who sells and services the make of
battery installed in your touring coach�
NOTE
Reconnect the battery cables to the correct
battery posts.

Battery Storage

During the winter, the batteries should be removed
from the touring coach and stored in a cool, dry place,
where there is no danger of freezing� They should be
kept full of water, cleaned, and charged monthly� A
battery that is allowed to completely lose its charge will
never regain its original power or a full charge�
The following recommendations may be helpful if the
battery is to be stored:
• When storing the battery in a vehicle or vessel, it is
not necessary to leave it on charge� Disconnect the
negative battery cable� This will prevent inadvertent
discharging of the battery which may lead to a
complete discharge�
• Fully charge the battery before putting it in storage
and store in a cool place�
• Charge the battery every 30 to 60 days to ensure
maximum battery life�
When storing your touring coach and leaving the
house batteries in place, it is recommended that the
vehicle be plugged into a 120-volt, 30-amp shoreline
connection for 24 to 48 hours every 30 days�
NOTE
A battery will self-discharge 1-3% per month at 80
degrees.
2017 Tommy Bahama TC