Adding 2nd House Battery - 2020 242x

[RSki]

I apologize in advance, but didn’t see the straight forward answer I was looking for on other threads. I just picked up my 2020 242x, and like most, the house battery can only handle 4-6 hours of running the stereo.

I want to add a 2nd house battery to help. What needs to be done to my stock setup to add a 2nd house battery? Do I need to add another switch or can I just add another battery in series to my existing house battery and nothing more?

Also, I see a lot of people getting the AGM Group 27 or 31 batteries. Can I run two different house batteries in series? (Stock batt and new AGM battery)? Sorry, not an electrician by any means ?

 

[Dixie Highway]

If you add another battery in series you will be pushing 24 volts, not a great idea. You’ll fry everything. A second battery in parallel would be a better idea, and you could in theory add it in parallel to the existing and be fine. Then both house batts would be on one switch and the starter separate. That’s probably the easiest method.

 

[ShesCrafty]

Does the 242x have the solar panel? That could do the trick. 4-6 hours of constant float mode, with stereo and transom shower compressor in use, barely puts a dent in my house battery level (242SE)... but it could be that your X model is running a second amp.

If you add a third battery, maybe test the added weight while on the water first. Make sure your boat doesn’t list to an extent that is bothersome to you.

 

[RSki]

If you add another battery in series you will be pushing 24 volts, not a great idea. You’ll fry everything. A second battery in parallel would be a better idea, and you could in theory add it in parallel to the existing and be fine. Then both house batts would be on one switch and the starter separate. That’s probably the easiest method.

That makes more sense!

 

[RSki]

Does the 242x have the solar panel? That could do the trick. 4-6 hours of constant float mode, with stereo and transom shower compressor in use, barely puts a dent in my house battery level (242SE)... but it could be that your X model is running a second amp.

If you add a third battery, maybe test the added weight while on the water first. Make sure your boat doesn’t list to an extent that is bothersome to you.

Yes, it has the singular solar panel. I think it trickle charges both batteries. Unfortunately after further review....they installed two starting batteries! Ugh ??‍

 

[F.M.]

2 starting batteries is a pretty typical move from dealers because they're cheaper. I'd start with just replacing your house battery with a Group 31 AGM. Mine lasts all day.

 

[Philip]

No issue if you run regular battery and an AGM?

 

[RSki]

I ended up with two AGM batteries in parallel. It now lasts all day (8 hrs) on the lake. I still have the annoying battery alarm if I shutoff the start battery. Key on or off, still get the alarm, even if using the Fushion head unit to power it on...

 

[212s]

I ended up with two AGM batteries in parallel. It now lasts all day (8 hrs) on the lake.

Do you have a battery charger? Most likely they won't get topped up by the charging system unless you have a long drive back to the dock.

I still have the annoying battery alarm if I shutoff the start battery. Key on or off, still get the alarm, even if using the Fushion head unit to power it on...

This is normal, the alarm is saying you have a start problem - there's no reason to shut off the start battery as the Switch/ACR isolates it from the house and does not drain it down while playing tunes. It's only purpose is to start the engines. You can confirm this with the battery voltage readings on the Connext. If everything is working properly, the house voltage will drop while the start does not.

 

[Merlion]

I ended up with two AGM batteries in parallel. It now lasts all day (8 hrs) on the lake. I still have the annoying battery alarm if I shutoff the start battery. Key on or off, still get the alarm, even if using the Fushion head unit to power it on...

What deep cycle batteries did you install in your boat? (I also have the 242x and I’m concerned about the linitted space given the ballast box