Converting to deep cycle coach batteries

[Jerelo0]

I'm finding that my coach battery power runs low over the course of 2 hours, rather than the 3 days of general use that they used to have. This happens with my little rechargables when they are end of life, and I'm guessing it's similar with these coach batteries. So I'm planning to replace the two type 24 hybrid batteries, which are auxilliary or coach batteries in a type C RV. 

I've read that I should use (switch to) true deep cycle batteries, rather than the hybrid type, since there is also an engine battery that I use to start the engine. But there is a button I can use if the engine battery is dead, allowing me to start from the coach batteries. This brought me to ask myself if the deep cycle batteries would still be capable of starting the engine if needed, or whether I require hybrid for that?

Any other problems with converting from hybrid coach batteries to true deep cycle batteries that I might be unaware of?

Also hoping for any thoughts on the the work involved in maintenance and checking of the regular deep cycle batteries versus no maintenance deep cycle batteries.

 

[Trebor English]

If your starter battery gets run down any coach battery can help start the engine.  According to the web page my battery should not be used for starting.  I avoid North Dakota in January and have no problem.  The one battery starts and does everything else too.  

Once a month I check the specific gravity with a hydrometer and add water.  It is 10 minutes once a month.  If your batteries are buried where you can't get to them it could be a problem.  

With flooded batteties you can check the acid to find out what the actual state of charge is.  You don't have to guess and buy new ones to see if that fixes it.  You can check to see if you are actually charging enough or are killing them.  You can measure.

 

[John61CT]

Depends on size.

If you only have room for a very small House bank, then it will not *on its own* have the same CCA cranking capacity as a Starter or dual-use/pseudo deep cycle of the same weight.

Obviously if your Starter is just a bit depleted (as opposed to completely shot) and you are *joining* the two banks (self-jumpstarting) then every bit helps.

But, once you get to a normal large AH capacity House bank, the lower CCA per lb becomes irrelevant, a pair of 200+AH GCs cycled down to 50% can still start even the biggest engine no worries.

Note if you are worried, a little jumpstarter powerpack kept *charged* in the glovebox is a great belt and suspenders fallback.

 

[DLTooley]

Should be no problem and your options of solving a dead starter battery are multiple with a solar system. Voltage drop between the house and starter batteries might be a factor, but it sounds like your system was designed for this. You can also use the solar to recharge the starter, though you might need to act as in lieu of an actual controller. Cold Charging Amps are less on a true deep cycle and that might be a factor in extremely cold conditions. Do check your system including your charge/usage numbers to make sure there isn't another problem at work.

Personally, I have an AGM for my starter battery and traditional deep cycle batteries for my house bank.

 

[Jerelo0]

Thanks all for the comments and answers. With the encouragement of a battery salesman, and this group, I got two of the deep cycle batteries. The RV use continues normally again, so all's well. Haven't yet needed to use the house batteries to start, but feel confident it won't be a problem.