Dead Chassis Batteries on New Aire

[WardSimmons]

I returned from a 1,200 mile trip last Friday and parked the New Aire in our outdoor storage spot. Today I went by and the electronic door code wouldn’t open the door - uh oh.

Inside I found the chassis batteries were at 4.2 volts. I used the battery boost switch to crank the engine, then took her on a good long ride to charge the batteries. I recognize that some permanent damage may have resulted from the batteries being this depleted.

Here’s the question - should I have disconnected the chassis batteries for a nine-day storage interval. This would surprise me. What draws the chassis battery down when the coach is parked? I can see some minor phantom drain might be present, but this seems excessive!

Ward Simmons

[turbopilot]

Originally Posted by WardSimmons

I can see some minor phantom drain might be present, but this seems excessive!

Did you leave a key FOB within 3 feet of start button?

[Sudsy]

I am surprised the unit doesn't have a battery switch. I would install one if I were you.


Sudsy

[uncnavy2000]

Originally Posted by WardSimmons

I returned from a 1,200 mile trip last Friday and parked the New Aire in our outdoor storage spot. Today I went by and the electronic door code wouldn’t open the door - uh oh.

Inside I found the chassis batteries were at 4.2 volts. I used the battery boost switch to crank the engine, then took her on a good long ride to charge the batteries. I recognize that some permanent damage may have resulted from the batteries being this depleted.

Here’s the question - should I have disconnected the chassis batteries for a nine-day storage interval. This would surprise me. What draws the chassis battery down when the coach is parked? I can see some minor phantom drain might be present, but this seems excessive!

Ward Simmons

I believe this is normal, the main reason being that SilverLeaf and other components have "constant power" even when the battery disconnect is turned off. My chassis batteries have never lasted a week with these constant draws so having power in storage is crucial unless you put in more real disconnects.

[Aegon]

Originally Posted by Sudsy

I am surprised the unit doesn't have a battery switch. I would install one if I were you.

It has a chassis battery disconnect. Mine is open, sitting outdoors for 7 days with chassis battery voltage holding steady at 12.7; we have a 10 watt solar panel feeding this system. I’m going to close the switch tomorrow and see what happens during the next week.

A schematic would be helpful to know what draws there are on the chassis batteries. I know, I know...

[WardSimmons]

Thanks everyone for the replies.

Turbo - No, the fob was not in the unit. My understanding is that the symptom there would be a dead key fob battery, not a dead chassis battery. Have I misunderstood that?

Sudsy - Yes, there is a battery disconnect switch. I did not use it, believing that for a nine-day period it was not necessary. That’s my question - what length of time do folks find requires the battery disconnect switch be used?

Uncnavy2000 - If I understand you correctly, you’re saying that the SilverLeaf draws power from the chassis batteries? I presumed (hard to find answers in the collection of manuals supplied with the unit) SilverLeaf was powered by the coach batteries. Although the coach battery were turned off at the disconnect switch, I knew SilverLeaf was still active. I expected the 400 watts of solar to maintain the coach batteries (which it has), including the associated SilverLeaf draw. If SilverLeaf is powered by the chassis batteries, that certainly does change things.

Aegon - Thanks for letting me know what happens when you close the chassis battery disconnect switch for a few days.

Since I don’t have access to power in storage, I suppose the simple answer is to just disconnect the chassis batteries whenever the coach is not in use. I can do that, but am surprised that it is necessary. Thanks again for any light anyone can shed. Maybe I’m overlooking it, but this should be answered in the manuals.

Ward Simmons

[turbopilot]

[QUOTE=WardSimmons;4127904I expected the 400 watts of solar to maintain the coach batteries (which it has), including the associated SilverLeaf draw. If SilverLeaf is powered by the chassis batteries, that certainly does change things.

[/QUOTE]

There is a bug in the SilverLeaf charging logic with solar. I have 1kw of solar but I have never seen the charge bridge open to the chassis battery when solar is charging the house.

Another SilverLeaf bug for the list.

My understanding is that both the FOB battery and chassis battery will deplete with FOB within 3 feet of ignition continuously.

[uncnavy2000]

Originally Posted by WardSimmons

Thanks everyone for the replies.



Uncnavy2000 - If I understand you correctly, you’re saying that the SilverLeaf draws power from the chassis batteries? I presumed (hard to find answers in the collection of manuals supplied with the unit) SilverLeaf was powered by the coach batteries. Although the coach battery were turned off at the disconnect switch, I knew SilverLeaf was still active. I expected the 400 watts of solar to maintain the coach batteries (which it has), including the associated SilverLeaf draw. If SilverLeaf is powered by the chassis batteries, that certainly does change things.


Ward Simmons

On my coach, everything up front including door keypad, lights, power chairs, monitors, etc are all wired to the chassis batteries. I believe Silverleaf is too. On a bit of a tangent, note that
the HWH slide is powered by the chassis batteries as well (I really wish this was on house). During factory pickup I was strongly encouraged to make sure the lightning bolt was visible on Silverleaf prior to deploying. Reason is if you don't, chassis batteries will temporarily drop into the 10v range while the slide is moving, and the slide may not travel out far enough before starting the vertical drop thanks to this low voltage.

[WardSimmons]

Turbo - Thanks for the info on both batteries discharging with the fob situation. How do you determine that the bridge to the chassis batteries is not opening? Is there an indicator somewhere?

Uncnavy2000 - I’ll have to try to locate the lightning bolt on the SilverLeaf display. I’ve never seen it, and didn’t know to look for it. I understand what you said about the voltage drop and the slide not completing its travel - thanks for the tip!

Ward Simmons

[Sudsy]

Sorry but I don't know what "Silverleaf" is! It really doesn't matter. There are many things that can draw current to kill a battery in storage Radio memories, CO2 monitors, clocks, etc. So I strongly recommend a battery switch. I have always had one. On a Travel Trailer right up front by the battery. I have never owned a 5th wheel. My Motor-home has two. If it's off it can't discharge!!!!!


I almost forgot!!!


It also has a lot to do about the condition of the storage batteries.



Sudsy

[turbopilot]

Originally Posted by WardSimmons

Turbo - Thanks for the info on both batteries discharging with the fob situation. How do you determine that the bridge to the chassis batteries is not opening? Is there an indicator somewhere?

I think it is the lightning bolt. Anytime I see it the house battery is in float with both the house and chassis battery are about the same voltage. I never see it before house battery goes into float.

I never see the lightning bolt when the house batteries are being charged by the solar cells, even when the solar controller goes into float. So I think SilverLeaf is watching the Xantrex charger. When it sees the charger go into float it closes the bridge between the house and chassis battery charging both.

There is no interface available in Newmar implementations of SilverLeaf to allow a connection between the solar charge controller and the TM102, so SilverLeaf does not know the solar charger is floating, thus it never opens the bridge to the chassis battery.

As to the RFID FOB, it is my understanding once the FOB is within 3 feet of the ignition circuit, it "wakes up several" circuits from the chassis battery taking more load from the chassis battery.

Much of this is guess and speculation by watching things work. Very little documentation on all of this.

Any time I leave the coach unplugged in the sunlight, I use a wedge to keep the switch for the battery link down, thus opening the chassis battery charge bridge to allow the big solar cells to keep both sets of batteries topped off.

[uncnavy2000]

The lightning bolt shows between the House & Chassis batteries on the main home screen; this is controlled by Silverleaf based on a variety of conditions (house batteries must be above a certain level, chassis batteries below etc). When the conditions are met, Silverleaf triggers a solenoid in the power reel compartment which bridges the charger to include the chassis batteries in addition to the house. Once it engages, it will stay open for a minimum of 20 minutes.

[turbopilot]

Originally Posted by uncnavy2000

The lightning bolt shows between the House & Chassis batteries on the main home screen; this is controlled by Silverleaf based on a variety of conditions (house batteries must be above a certain level, chassis batteries below etc). When the conditions are met, Silverleaf triggers a solenoid in the power reel compartment which bridges the charger to include the chassis batteries in addition to the house. Once it engages, it will stay open for a minimum of 20 minutes.

That agrees with what I am seeing. In the NA the solenoid is back by the chassis battery switch near the engine.

[Aegon]

Originally Posted by uncnavy2000

The lightning bolt shows between the House & Chassis batteries on the main home screen; this is controlled by Silverleaf based on a variety of conditions (house batteries must be above a certain level, chassis batteries below etc).

This tracks with a demonstration our FPU Tech showed me. We were plugged in with all batteries fully charged, no lightning bolt on the main SilverLeaf display.
He turned on the headlights to drop the chassis battery voltage and the lightening bolt came on, bridging the chassis & house batteries.