Coach Battery

Dakzuki wrote:
"The Best of Both Worlds.". Actually a compromise between both worlds.

'zacly what I've always thought. The Walmart "Marine Start" batteries in our boat, and the Walmart "Deep Cycle Trolling Motor" battery in our coach "house" only carry a one-year warranty, but they actually last more like three years or so. About what warranty would be if I tried to use car batteries instead.

"Dual" is more like "Neither." If you don't have the room for two, just get the biggest true Deep Cycle that'll fit your House Battery compartment.

In many cases, you CAN expand the compartment. As I noted above, depends on how you use the RV. For example,
width=320[/img]This is our Jayco. The "compartment" is more like a "hole." It has no front, no bottom, extends back to the Chassis, and its only rear is the front of the next compartment. Another Jayco owner modified the area to accept a two-battery tray, and ordered a bigger door for the enlarged cutout he made in coach body. Still another converted the area behind the battery (white plate is CATV Jack) where the shore tie cable stores. Basically left one battery where it is, installed another in the re-purposed compartment. All I did, was convert our permanently mounted battery tray to a pull-out. Used heavy duty drawer slides from Home Depot. I'm happy with the result. Can check water now. Also, project justified buying an angle drill!

j-d wrote:

theoldwizard1 wrote:
True deep cycle 12V batteries are NOT very common. Any battery that advertises a CCA or MCA rating is probably not a TRUE deep cycle battery, but instead a dual purpose "marine" battery.

He's right! The Cranking Amps gives it away. From gOOgle for this battery:

DC27 Deka 12 Volt 650 CCA/ 800 CA 175 Res/Cap Deep Cycle (Gr 27) Deka Marine Master Flooded Batteries. Deep Cycle/Starting – The Best of Both Worlds. High starting and deep cycle capability; Longer cycling than starting battery; Extra reserve power for accessory loads; Rugged vibration-resistant construction.

I don't know if Dual Purpose Batteries are as good for Starting as a pure Starting Battery, but Dual Purpose is NOT as good as Deep Cycle for applications like an RV "House" or a Trolling Motor.

Whether you need two or more batteries, depends on how you use the RV. We get by very well on one true Deep Cycle from Walmart but we don't boondock.

"The Best of Both Worlds.". Actually a compromise between both worlds.

theoldwizard1 wrote:
True deep cycle 12V batteries are NOT very common. Any battery that advertises a CCA or MCA rating is probably not a TRUE deep cycle battery, but instead a dual purpose "marine" battery.

He's right! The Cranking Amps gives it away. From gOOgle for this battery:

DC27 Deka 12 Volt 650 CCA/ 800 CA 175 Res/Cap Deep Cycle (Gr 27) Deka Marine Master Flooded Batteries. Deep Cycle/Starting – The Best of Both Worlds. High starting and deep cycle capability; Longer cycling than starting battery; Extra reserve power for accessory loads; Rugged vibration-resistant construction.

I don't know if Dual Purpose Batteries are as good for Starting as a pure Starting Battery, but Dual Purpose is NOT as good as Deep Cycle for applications like an RV "House" or a Trolling Motor.

Whether you need two or more batteries, depends on how you use the RV. We get by very well on one true Deep Cycle from Walmart but we don't boondock.

The battery is on a slide box inside of an access door. It came with the rig when I bought it new. Wish I had enough space for two. I can go a bit bigger. Will need to measure. Thanks for the help!!

True deep cycle 12V batteries are NOT very common. Any battery that advertises a CCA or MCA rating is probably not a TRUE deep cycle battery, but instead a dual purpose "marine" battery.

One example of a true deep cycle battery is the Trojan T-1275. Open your wallet WIDE !

Cruisineasy wrote:
I have a 2011 31' Jayco Greyhawk DS. The coach battery is failing and needs to be replaced. It currently has a Marine Master DP 27. 650 Cold cranking amps. Since it only has one battery I would like something that will last longer between charges. Would one with 850 Cold cranking amps work better?? Any help on this would be appreciated..

Is there a reason that it is a Group 27? If you have the space go larger for sure or 2 - 6V. OR if you can maybe look to relocate the battery to get bigger that would be an idea as well.

klutchdust wrote:
Looking at the brochure for your coach I see they refer to "the battery". I would be curious to see the actual battery area and see if there was room to have another batter carrier installed and then throw 2 Trojan 6 volt deep cycles in there. I upgraded to them and the difference is remarkable.

I "second" this advice if your rig can accommodate two 6V batteries.

I did not buy Trojan batteries but rather Duracell brand 6V AGM batteries at Costco for $170 each. The batteries prior were two deep cycle marine 12V batteries from Walmart. The difference is night-& day. The difference would be bigger yet if we had only one 12V battery.

Dakzuki wrote:

Cobra21 wrote:
The larger cold cranking amps may also indicate more amp. hours. I do pay attention to cold cranking amps, as my house battery also starts my generator.
Brian

It is not a direct relationship because CCA indicates surge capability for heavy short loads. A generator starter is far from that.

The generator starter is a reasonably heavy load. Mine averages somewhere in the vicinity of 100A when it's cranking, according to my panel ammeter, give or take a fair bit. Compared to other typical house loads if one doesn't have a largish inverter, it's certainly an outlier.

Cobra21 wrote:
The larger cold cranking amps may also indicate more amp. hours. I do pay attention to cold cranking amps, as my house battery also starts my generator.
Brian

It is not a direct relationship because CCA indicates surge capability for heavy short loads. A generator starter is far from that.

I have been very happy with my 12 volt Deep cycle batteries from Costco, now about 7 years old.

I killed the pair that came with our used MH. Somehow I got the idea that I could sort of trust the three light battery indicator and that all was well if the voltage was higher than 12.5. In fact, with only a little charging the battery goes way over 13 volts and the idiot lights indicate a full charge. It can take hours for the temporary surface charge voltage to reach its steady state and provide a decently accurate state of charge. Below 50% charge, damage begins. Only a battery monitor showing the % of full charge for counting amp hours going in and out provides a really good indication. Even my $25 eBay one works very well. It was a bit complicated to install because all current to and from the battery(s) must flow through it.