Battery life while using furnace?

[xo1rider]

Dry camping at a State Park near the N. California Coast. Got here yesterday afternoon. When I got up this morning the battery indicator on the status panel was glowing bright green.

Turned the furnace on to take the chill out of the trailer (temps in the low 50s). Soon as the blower motor got going full blast the indicator light went from green to red, then blinking red. Turned off the furnace (it was on maybe 15 minutes). Once the furnace was off the indicator went to yellow.

I know not to trust the indicators too much but was wondering if that sounds somewhat normal? Trailer is about 2 years old and I routinely check the fluid level in the batteries. it was in storage for about 60 days prior to this trip but was plugged in at home for 24 hours prior to the short two hour drive to the park.

Generator hours start in three hours and I'll pump them back up then. Right now all seems good with the lights etc. I suspect I could have left the furnace going but really just wanted to get the chill out of the trailer.

Thanks..

[moosetags]

I have found that the gas furnace motor is the single biggest draw of battery power. That being said, the situation that you describe indicates that something is amiss. Your indicator may be giving you a false reading, but it is just as likely that your batteries have a problem. Even though only a year old, one of your batteries could have a bad cell causing a significant performance problem. You may also have a converter problem that is resulting in the batteries not being fully charged.

The only way to know for sure is to test these components to see what is going on.

Brian

[dznf0g]

Last week I was out dry camping and the weather was down in the 40's at night. I have a TriMetric monitor and after running the furnace all night and some (LED) lighting, I was down to 74% in the morning. IIRC the voltage was about 12.5V.
A 12.5V level could trigger a yellow light while resting.....depends on the indicator programming. You might try voltmeter to test the levels at which the various lights come on....for future point of reference. As I recall 12.2 Volts is a 50% state of charge, and you should strive to not regularly go below a 50% state of charge, as that practice can shorten battery life.

[dkottum]

Most auto accessory stores have little voltmeters that plug in the 12vdc receptacles (cigarette lighter) on your trailer. Actually knowing the voltage will give you a much better idea what's going on. I think your Airstream owners manual has a chart showing voltage to percent of battery remaining.

Are you still under warranty? Calling Airstream Customer Service may help.

doug k

[idroba]

Airstream propane detector monitors are wired so they bypass the store switch and take power 24/7. If your unit was in storage with no charging for 60 days prior to the home stay and 24 hour charge the batteries may not have been recharged, and/or have been damaged by the long term deep discharge from the constantly on detector.

I don't think much of the system which allows a constant discharge of the batteries over time. The load is not huge, of course, but it nibbles away at the batteries, and once they have become badly discharged, they will never be able to recharge fully.

I would guess you will be in the market for new batteries soon.

BTW, this is from the 2013 FC manual. First they say the store switch disconnects everything from the battery:

"When the switch is turned to STORe (off) and the trailer is plugged into a 110-volt shoreline, the 12- volt distribution panel will still receive power from the converter, but the batteries are disconnected from the system. The batteries will not be drained with the switch in the store position. The converter will not charge the batteries with the switch in this position".

Then they say:

"your lPG detector is wired directly to your trailer battery and incorporates a 1 amp, in-line fuse. It has no internal battery backup. In normal stand-by mode, the leD indicator will be green".

So, it is always on.......and does not disconnect with the store switch.

[jdalrymple]

The furnace is a large current draw. We use it some, but when paying for hook-ups at a campground, we use the "free" electricity.

When dry camping, I use a propane radiant heater to provide a base amount of heat and use the furnace to warm up a bit more during a shower or such.

I have used the furnace for all heat, but a battery recharge will be required every morning.

The other issue is the battery monitor. It is very basic at best and because it can only display a few LEDs as indicators, it cannot give true voltage reading.

Your batteries may not be completely drained.

As mention above a true volt meter will give you better results in determining condition.

[dkottum]

Consider installing a solar system with Lifeline batteries. You will have charged batteries when you need them and eliminate the storage discharge problem (unless stored indoors).

When hooked to external power for more than a day, be sure to use the "Store" position on the battery disconnect to isolate your batteries from your converter. No matter what batteries you use.

doug k

[panora2]

Need some info: The inverter switch or "close" switch as some call it is located behind our front window curtain on the street side. I cannot tell if it's on or off! I see no words to indicate or Letters to indicate either setting. Can someone tell me where I could volt test this switch. Possibly take off the plate? would that expose the wires so I could get a testor on that? I'm not exactly happy with the so called manual and it's explanations.
Thanks for any help in advance.

[Skater]

Originally Posted by panora2

Need some info: The inverter switch or "close" switch as some call it is located behind our front window curtain on the street side. I cannot tell if it's on or off! I see no words to indicate or Letters to indicate either setting. Can someone tell me where I could volt test this switch. Possibly take off the plate? would that expose the wires so I could get a testor on that? I'm not exactly happy with the so called manual and it's explanations.
Thanks for any help in advance.

In mine, up is on and down is off. The safest thing (though it may require some contortions) would be to check power at the outlet where the converter is plugged in, since that's the outlet it's controlling. Mine is under the front couch.

(Also, the device that takes 120 volt AC power and changes it to 12 volt DC power is normally called a "converter" in RV circles, and "inverter" is reserved for the device that does the reverse. In electrical circles they are both inverters though.)

[DKB_SATX]

Originally Posted by Skater

In mine, up is on and down is off. The safest thing (though it may require some contortions) would be to check power at the outlet where the converter is plugged in, since that's the outlet it's controlling. Mine is under the front couch.

(Also, the device that takes 120 volt AC power and changes it to 12 volt DC power is normally called a "converter" in RV circles, and "inverter" is reserved for the device that does the reverse. In electrical circles they are both inverters though.)

In electrical circles what we call a converter would more specifically be called a rectifier, no?

[Bill M.]

Furnace will go maybe a couple of nights on a low setting if it is not too cold out. I agree with checking the battery voltage. I know on our older Airstream the monitor goes from excellent to good with very little draw. You almost have to have it plugged in to get excellent.

[handn]

Running your furnace for a short time will not discharge a fully charged batteries in good condition. We boondock regularly and camp in the fall in the mountains when temps go below freezing. Total run time on the furnace may be near an hour and the batteries have a little left in the morning.
I agree with the poster who suggested plugging a multi meter into the 12 volt power supply. Test the voltage after the furnace has shut off. Healthy batteries should read in the 12.8 12.7 after the furnace shuts off.
You will have to trouble shoot the reason for a low reading. If the batteries are two or more years old, worn out batteries is the likely reason.
Single stage converters (Paralax) will ruin a battery in a hurry if the trailer is plugged in.
Replacing the batteries without changing the converter is frustrating because the need for new batteries occurs quickly. Agm's such as Optimas hate being overcharged. It is doubly frustrating to replace them prematurely because they are costly. A multi stage converter costs about $250 (bestconverter.com) and can be installed by a patient do it yourselfer.
If the batteries are new, your problem is due to an unanticipated current drain. The cause of a rapid discharge is something that uses a lot of juice in a hurry. It is not likely to be the propane detector because one in good condition uses almost no juice. Leave your multi meter hooked up to the 12 volt power supply and start pulling fuses. When you get a jump on the dial of the multi meter, when you pull a fuse, your problem is in that circuit.
If you are going to boondock a lot a generator and a good solar charging system will enable multiple day trouble, free stays. My 200 watt solar charger greatly reduces the necessary generator run time and enables me to comfortably camp in fall weather.

[Skater]

Originally Posted by DKB_SATX

In electrical circles what we call a converter would more specifically be called a rectifier, no?

You're right - thanks.

[dlb435]

I can get about one really cold night out of my battery.
I just used my TV to recharge the battery. It works fine for occasional use. I would go solar or a small gen set for long term use.

[dkottum]

When I was a Navy aircraft electricians mate, an inverter changed DC to AC. A rectifier changed AC to DC.

doug k